Merge pull request #35 from red0124/feature/csv_buffer

Feature/csv buffer

.github/workflows/coverage.yml

@@ -46,10 +46,13 @@ jobs:
       - name: Install test coverage tools
         run: |
           apt update
-          apt install -y gcovr lcov
+          apt install -y gcovr
+
+      - name: Install lcov2.0
+        run: script/ci_install_lcov.sh
 
       - name: Configure
-        run: cmake -S test -B build -D CMAKE_BUILD_TYPE=Debug -D CMAKE_CXX_FLAGS="-Wall -fprofile-arcs -ftest-coverage --coverage"
+        run: cmake -S test -B build -D CMAKE_BUILD_TYPE=Debug -D CMAKE_CXX_FLAGS="-Wall -fprofile-arcs -ftest-coverage --coverage -fno-elide-constructors -fno-default-inline"
 
       - name: Build
         run: cmake --build build -j ${{steps.cores.outputs.count}}
@@ -60,7 +63,7 @@ jobs:
 
       - name: Generate coverage report
         run: |
-          lcov -d . -c -o out.info --rc lcov_branch_coverage=1 --no-external
+          lcov -d . -c -o out.info --rc branch_coverage=1 --no-external --filter branch --filter line --ignore-errors mismatch
           lcov -e out.info '*include/ss*hpp' -o filtered.info
 
       - name: Invoke coveralls

.gitignore

@@ -6,5 +6,3 @@ build/
 hbuild/
 subprojects/*
 !subprojects/*.wrap
-ssp.cpp
-ssp.bin

README.md

@@ -17,13 +17,13 @@
 [![windows-msys2-clang](https://github.com/red0124/ssp/workflows/win-msys2-clang-ci/badge.svg)](https://github.com/red0124/ssp/actions/workflows/win-msys2-clang.yml)
 [![windows-msvc](https://github.com/red0124/ssp/workflows/win-msvc-ci/badge.svg)](https://github.com/red0124/ssp/actions/workflows/win-msvc.yml)
 
-A header only "csv" parser which is fast and versatile with modern C++ api. Requires compiler with C++17 support. [Can also be used to convert strings to specific types.](#the-converter)
+A header only CSV parser which is fast and versatile with modern C++ API. Requires compiler with C++17 support. [Can also be used to efficiently convert strings to specific types.](#the-converter)
 
 Conversion for floating point values invoked using [fast-float](https://github.com/fastfloat/fast_float) . \
 Function traits taken from *qt-creator* .
 
 # Example 
-Lets say we have a csv file containing students in a given format \<Id,Age,Grade\> and we want to parse and print all the valid values:
+Lets say we have a CSV file containing students in a given format (Id,Age,Grade) and we want to parse and print all the valid values:
 
 ```shell
 $ cat students.csv
@@ -58,6 +58,7 @@ Bill (Heath) Gates 65 3.3
  * Can work without exceptions
  * [Works with headers](#headers)
  * [Works with quotes, escapes and spacings](#setup)
+ * [Works with CSV data stored in buffers](#buffer-mode)
  * [Works with values containing new lines](#multiline)
  * [Columns and rows can be ignored](#special-types)
  * [Works with any type of delimiter](#delimiter)
@@ -158,7 +159,7 @@ while (!p.eof()) {
 
 The alternate example with exceptions disabled will be used to show some of the features of the library. The **`get_next`** method returns a tuple of objects specified inside the template type list.
 
-If a conversion could not be applied, the method would return a tuple of default constructed objects, and the **`valid`** method would return **`false`**, for example if the third (grade) column in our csv could not be converted to a float the conversion would fail.
+If a conversion could not be applied, the method would return a tuple of default constructed objects, and the **`valid`** method would return **`false`**, for example if the third (grade) column in our CSV could not be converted to a float the conversion would fail.
 
 If **`get_next`** is called with a **`tuple`** as template parameter it would behave identically to passing the same tuple parameters to **`get_next`**:
 ```cpp
@@ -202,14 +203,27 @@ struct student {
     auto tied() { return std::tie(id, age, grade); }
 };
 ```
-The method can be used to compare the object, serialize it, deserialize it, etc. Now **`get_next`** can accept such a struct and deduce the types to which to convert the csv.
+The method can be used to compare the object, serialize it, deserialize it, etc. Now **`get_next`** can accept such a struct and deduce the types to which to convert the CSV.
 ```cpp
 // returns student
 auto s = p.get_next<student>();
 ```
 This works with the iteration loop too.
-*Note, the order in which the members of the tied method are returned must match the order of the elements in the csv*.
+*Note, the order in which the members of the tied method are returned must match the order of the elements in the CSV*.
 
+## Buffer mode
+The parser also works with buffers containing CSV data instead of files. To parse buffer data with the parser simply create the parser by giving it the buffer, as **`const char*`**, and its size. The initial example using a buffer instead of a file would look similar to this:
+```cpp
+std::string buffer = "James Bailey,65,2.5\nBrian S. Wolfe,40,1.9\n";
+
+ss::parser<ss::throw_on_error> p{buffer.c_str(), buffer.size()};
+
+for (const auto& [id, age, grade] : p.iterate<std::string, int, float>()) {
+    std::cout << id << ' ' << age << ' ' << grade << std::endl;
+}
+
+return 0;
+```
 ## Setup
 By default, many of the features supported by the parser are disabled. They can be enabled within the template parameters of the parser. For example, to enable quoting and escaping the parser would look like:
 ```cpp
@@ -241,7 +255,7 @@ Empty lines can be ignored by defining **`ss::ignore_empty`** within the setup p
 ```cpp
 ss::parser<ss::ignore_empty> p{file_name};
 ```
-If this setup option is not set then reading an empty line will result in an error (unless only one column is present within the csv).
+If this setup option is not set then reading an empty line will result in an error (unless only one column is present within the CSV).
 
 ### Quoting
 Quoting can be enabled by defining **`ss::quote`** within the setup parameters. A single character can be defined as the quoting character, for example to use **`"`** as a quoting character:
@@ -290,7 +304,7 @@ Escaping and quoting can be used to leave the space if needed.
 ```
 
 ### Multiline
-Multiline can be enabled by defining **`ss::multilne`** within the setup parameters. It enables the possibility to have the new line characters within rows. The new line character needs to be either escaped or within quotes so either **`ss::escape`** or **`ss::quote`** need to be enabled. There is a specific problem when using multiline, for example, if a row had an unterminated quote, the parser would assume it to be a new line within the row, so until another quote is found, it will treat it as one line which is fine usually, but it can cause the whole csv file to be treated as a single line by mistake. To prevent this **`ss::multiline_restricted`** can be used which accepts an unsigned number representing the maximum number of lines which can be allowed as a single multiline. Examples:
+Multiline can be enabled by defining **`ss::multilne`** within the setup parameters. It enables the possibility to have the new line characters within rows. The new line character needs to be either escaped or within quotes so either **`ss::escape`** or **`ss::quote`** need to be enabled. There is a specific problem when using multiline, for example, if a row had an unterminated quote, the parser would assume it to be a new line within the row, so until another quote is found, it will treat it as one line which is fine usually, but it can cause the whole CSV file to be treated as a single line by mistake. To prevent this **`ss::multiline_restricted`** can be used which accepts an unsigned number representing the maximum number of lines which can be allowed as a single multiline. Examples:
 
 ```cpp
 ss::parser<ss::multiline, ss::quote<'\"'>, ss::escape<'\\'>> p{file_name};
@@ -341,7 +355,7 @@ Gates 65 3.3'
 ```
 ## Special types
 
-Passing **`void`** makes the parser ignore a column. In the initial example **`void`** could be given as the second template parameter to ignore the second (age) column in the csv, a tuple of only 2 parameters would be retuned:
+Passing **`void`** makes the parser ignore a column. In the initial example **`void`** could be given as the second template parameter to ignore the second (age) column in the CSV, a tuple of only 2 parameters would be retuned:
 ```cpp
 // returns std::tuple<std::string, float>
 auto [id, grade] = p.get_next<std::string, void, float>();
@@ -383,6 +397,12 @@ if (std::holds_alternative<float>(grade)) {
     // grade set as char
 }
 ```
+Passing **`char`** and types that are aliases to it such as **`uint8_t`** and **`int8_t`** make the parser interpret the input data as a single character in a similar way to how **`std::cin`** does it. To read numeric values into something like **`uint8_t`** the **`ss::uint8`** and **`ss::int8`** types can be used. These are wrappers arround the corresponding char aliases and can be implicitly converted to and from them. When these types are given to the parser he will try to read the given data and store it in the underlying element, but this time as a numeric value instead of a single character.
+```cpp
+// returns std::tuple<std::string, ss::uint8, float>
+auto [id, age, grade] = p.get_next<std::string, ss::uint8, float>();
+uint8_t age_copy = age;
+```
 ## Restrictions
 
 Custom **`restrictions`** can be used to narrow down the conversions of unwanted values. **`ss::ir`** (in range) and **`ss::ne`** (none empty) are some of those:
@@ -454,12 +474,13 @@ The **`eof`** method can be used to detect if the end of the file was reached.
 Detailed error messages can be accessed via the **`error_msg`** method, and to enable them **`ss::string_error`** needs to be included in the setup. If **`ss::string_error`** is not defined, the **`error_msg`** method will not be defined either.
 
 The line number can be fetched using the **`line`** method.
-
+The cursor position can be fetched using the **`position`** method.
 ```cpp
-const std::string& parser::error_msg();
+const std::string& parser::error_msg() const;
-bool parser::valid();
+bool parser::valid() const;
-bool parser::eof();
+bool parser::eof() const;
-size_t parser::line();
+size_t parser::line() const;
+size_t parser::position() const;
 
 // ...
 ss::parser<ss::string_error> parser;
@@ -474,7 +495,7 @@ ss::parser<ss::throw_on_error> parser;
 
 ## Substitute conversions
 
-The parser can also be used to effectively parse files whose rows are not always in the same format (not a classical csv but still csv-like). A more complicated example would be the best way to demonstrate such a scenario.\
+The parser can also be used to effectively parse files whose rows are not always in the same format (not a classical CSV but still CSV-like). A more complicated example would be the best way to demonstrate such a scenario.\
 ***Important, substitute conversions do not work when throw_on_error is enabled.***
 
 Supposing we have a file containing different shapes in given formats: 

include/ss/common.hpp

@@ -28,15 +28,24 @@ inline void assert_throw_on_error_not_defined() {
                                  "'throw_on_error' is enabled");
 }
 
+inline void* strict_realloc(void* ptr, size_t size) {
+    ptr = std::realloc(ptr, size);
+    if (!ptr) {
+        throw std::bad_alloc{};
+    }
+
+    return ptr;
+}
+
 #if __unix__
-inline ssize_t get_line(char** lineptr, size_t* n, FILE* stream) {
+inline ssize_t get_line_file(char** lineptr, size_t* n, FILE* stream) {
     return getline(lineptr, n, stream);
 }
 #else
 
-using ssize_t = int64_t;
+using ssize_t = intptr_t;
 
-ssize_t get_line(char** lineptr, size_t* n, FILE* fp) {
+ssize_t get_line_file(char** lineptr, size_t* n, FILE* fp) {
     if (lineptr == nullptr || n == nullptr || fp == nullptr) {
         errno = EINVAL;
         return -1;
@@ -46,36 +55,24 @@ ssize_t get_line(char** lineptr, size_t* n, FILE* fp) {
 
     if (*lineptr == nullptr || *n < sizeof(buff)) {
         size_t new_n = sizeof(buff);
-        auto new_lineptr = static_cast<char*>(realloc(*lineptr, new_n));
+        *lineptr = static_cast<char*>(strict_realloc(*lineptr, new_n));
-        if (new_lineptr == nullptr) {
-            errno = ENOMEM;
-            return -1;
-        }
-
-        *lineptr = new_lineptr;
         *n = new_n;
     }
 
     (*lineptr)[0] = '\0';
 
-    while (fgets(buff, sizeof(buff), fp) != nullptr) {
+    size_t line_used = 0;
-        size_t line_used = strlen(*lineptr);
+    while (std::fgets(buff, sizeof(buff), fp) != nullptr) {
-        size_t buff_used = strlen(buff);
+        line_used = std::strlen(*lineptr);
+        size_t buff_used = std::strlen(buff);
 
         if (*n <= buff_used + line_used) {
             size_t new_n = *n * 2;
-
+            *lineptr = static_cast<char*>(strict_realloc(*lineptr, new_n));
-            auto new_lineptr = static_cast<char*>(realloc(*lineptr, new_n));
-            if (new_lineptr == nullptr) {
-                errno = ENOMEM;
-                return -1;
-            }
-
-            *lineptr = new_lineptr;
             *n = new_n;
         }
 
-        memcpy(*lineptr + line_used, buff, buff_used);
+        std::memcpy(*lineptr + line_used, buff, buff_used);
         line_used += buff_used;
         (*lineptr)[line_used] = '\0';
 
@@ -84,7 +81,7 @@ ssize_t get_line(char** lineptr, size_t* n, FILE* fp) {
         }
     }
 
-    return -1;
+    return (line_used != 0) ? line_used : -1;
 }
 
 #endif

include/ss/extract.hpp

@@ -77,6 +77,38 @@ std::enable_if_t<std::is_floating_point_v<T>, std::optional<T>> to_num(
 
 #endif
 
+////////////////
+// numeric_wrapper
+////////////////
+
+template <typename T>
+struct numeric_wrapper {
+    using type = T;
+
+    numeric_wrapper() = default;
+    numeric_wrapper(numeric_wrapper&&) = default;
+    numeric_wrapper(const numeric_wrapper&) = default;
+
+    numeric_wrapper& operator=(numeric_wrapper&&) = default;
+    numeric_wrapper& operator=(const numeric_wrapper&) = default;
+
+    numeric_wrapper(T other) : value{other} {
+    }
+
+    operator T() {
+        return value;
+    }
+
+    operator T() const {
+        return value;
+    }
+
+    T value;
+};
+
+using int8 = numeric_wrapper<int8_t>;
+using uint8 = numeric_wrapper<uint8_t>;
+
 template <typename T>
 std::enable_if_t<std::is_integral_v<T>, std::optional<T>> to_num(
     const char* const begin, const char* const end) {
@@ -89,6 +121,18 @@ std::enable_if_t<std::is_integral_v<T>, std::optional<T>> to_num(
     return ret;
 }
 
+template <typename T>
+std::enable_if_t<is_instance_of_v<numeric_wrapper, T>, std::optional<T>> to_num(
+    const char* const begin, const char* const end) {
+    T ret;
+    auto [ptr, ec] = std::from_chars(begin, end, ret.value);
+
+    if (ec != std::errc() || ptr != end) {
+        return std::nullopt;
+    }
+    return ret;
+}
+
 ////////////////
 // extract
 ////////////////
@@ -103,7 +147,8 @@ struct unsupported_type {
 template <typename T>
 std::enable_if_t<!std::is_integral_v<T> && !std::is_floating_point_v<T> &&
                      !is_instance_of_v<std::optional, T> &&
-                     !is_instance_of_v<std::variant, T>,
+                     !is_instance_of_v<std::variant, T> &&
+                     !is_instance_of_v<numeric_wrapper, T>,
                  bool>
 extract(const char*, const char*, T&) {
     static_assert(error::unsupported_type<T>::value,
@@ -112,7 +157,9 @@ extract(const char*, const char*, T&) {
 }
 
 template <typename T>
-std::enable_if_t<std::is_integral_v<T> || std::is_floating_point_v<T>, bool>
+std::enable_if_t<std::is_integral_v<T> || std::is_floating_point_v<T> ||
+                     is_instance_of_v<numeric_wrapper, T>,
+                 bool>
 extract(const char* begin, const char* end, T& value) {
     auto optional_value = to_num<T>(begin, end);
     if (!optional_value) {
@@ -169,9 +216,9 @@ inline bool extract(const char* begin, const char* end, bool& value) {
         }
     } else {
         size_t size = end - begin;
-        if (size == 4 && strncmp(begin, "true", size) == 0) {
+        if (size == 4 && std::strncmp(begin, "true", size) == 0) {
             value = true;
-        } else if (size == 5 && strncmp(begin, "false", size) == 0) {
+        } else if (size == 5 && std::strncmp(begin, "false", size) == 0) {
             value = false;
         } else {
             return false;

include/ss/parser.hpp

@@ -5,6 +5,7 @@
 #include "exception.hpp"
 #include "extract.hpp"
 #include "restrictions.hpp"
+#include <cerrno>
 #include <cstdlib>
 #include <cstring>
 #include <optional>
@@ -48,6 +49,23 @@ public:
         }
     }
 
+    parser(const char* const csv_data_buffer, size_t csv_data_size,
+           const std::string& delim = ss::default_delimiter)
+        : file_name_{"buffer line"},
+          reader_{csv_data_buffer, csv_data_size, delim} {
+        if (csv_data_buffer) {
+            read_line();
+            if constexpr (ignore_header) {
+                ignore_next();
+            } else {
+                raw_header_ = reader_.get_buffer();
+            }
+        } else {
+            handle_error_null_buffer();
+            eof_ = true;
+        }
+    }
+
     parser(parser&& other) = default;
     parser& operator=(parser&& other) = default;
 
@@ -84,10 +102,14 @@ public:
     }
 
     size_t line() const {
-        return reader_.line_number_ > 1 ? reader_.line_number_ - 1
+        return reader_.line_number_ > 0 ? reader_.line_number_ - 1
                                         : reader_.line_number_;
     }
 
+    size_t position() const {
+        return reader_.chars_read_;
+    }
+
     template <typename T, typename... Ts>
     no_void_validator_tup_t<T, Ts...> get_next() {
         std::optional<std::string> error;
@@ -192,7 +214,7 @@ public:
         reader_.next_line_converter_.set_column_mapping(column_mappings,
                                                         header_.size());
 
-        if (line() == 1) {
+        if (line() == 0) {
             ignore_next();
         }
     }
@@ -351,7 +373,10 @@ public:
 
         template <typename U, typename... Us, typename Fun = none>
         void try_convert_and_invoke(std::optional<U>& value, Fun&& fun) {
-            if (!parser_.valid()) {
+            if (parser_.valid()) {
+                return;
+            }
+
             auto tuple_output = try_same<Us...>();
             if (!parser_.valid()) {
                 return;
@@ -365,7 +390,6 @@ public:
 
             parser_.try_invoke(*value, std::forward<Fun>(fun));
         }
-        }
 
         template <typename U, typename... Us>
         no_void_validator_tup_t<U, Us...> try_same() {
@@ -512,6 +536,19 @@ private:
         }
     }
 
+    void handle_error_null_buffer() {
+        constexpr static auto error_msg = " received null data buffer";
+
+        if constexpr (string_error) {
+            error_.clear();
+            error_.append(file_name_).append(error_msg);
+        } else if constexpr (throw_on_error) {
+            throw ss::exception{file_name_ + error_msg};
+        } else {
+            error_ = true;
+        }
+    }
+
     void handle_error_file_not_open() {
         constexpr static auto error_msg = " could not be opened";
 
@@ -638,21 +675,30 @@ private:
 
     struct reader {
         reader(const std::string& file_name_, const std::string& delim)
-            : delim_{delim}, file_{fopen(file_name_.c_str(), "rb")} {
+            : delim_{delim}, file_{std::fopen(file_name_.c_str(), "rb")} {
+        }
+
+        reader(const char* const buffer, size_t csv_data_size,
+               const std::string& delim)
+            : delim_{delim}, csv_data_buffer_{buffer},
+              csv_data_size_{csv_data_size} {
         }
 
         reader(reader&& other)
             : buffer_{other.buffer_},
               next_line_buffer_{other.next_line_buffer_},
-              helper_buffer_{other.helper_buffer_}, converter_{std::move(
+              helper_buffer_{other.helper_buffer_},
-                                                        other.converter_)},
+              converter_{std::move(other.converter_)},
               next_line_converter_{std::move(other.next_line_converter_)},
               buffer_size_{other.buffer_size_},
               next_line_buffer_size_{other.next_line_buffer_size_},
-              helper_size_{other.helper_size_}, delim_{std::move(other.delim_)},
+              helper_buffer_size{other.helper_buffer_size},
-              file_{other.file_}, crlf_{other.crlf_},
+              delim_{std::move(other.delim_)}, file_{other.file_},
-              line_number_{other.line_number_}, next_line_size_{
+              csv_data_buffer_{other.csv_data_buffer_},
-                                                    other.next_line_size_} {
+              csv_data_size_{other.csv_data_size_},
+              curr_char_{other.curr_char_}, crlf_{other.crlf_},
+              line_number_{other.line_number_}, chars_read_{other.chars_read_},
+              next_line_size_{other.next_line_size_} {
             other.buffer_ = nullptr;
             other.next_line_buffer_ = nullptr;
             other.helper_buffer_ = nullptr;
@@ -668,29 +714,34 @@ private:
                 next_line_converter_ = std::move(other.next_line_converter_);
                 buffer_size_ = other.buffer_size_;
                 next_line_buffer_size_ = other.next_line_buffer_size_;
-                helper_size_ = other.helper_size_;
+                helper_buffer_size = other.helper_buffer_size;
                 delim_ = std::move(other.delim_);
                 file_ = other.file_;
+                csv_data_buffer_ = other.csv_data_buffer_;
+                csv_data_size_ = other.csv_data_size_;
+                curr_char_ = other.curr_char_;
                 crlf_ = other.crlf_;
                 line_number_ = other.line_number_;
+                chars_read_ = other.chars_read_;
                 next_line_size_ = other.next_line_size_;
 
                 other.buffer_ = nullptr;
                 other.next_line_buffer_ = nullptr;
                 other.helper_buffer_ = nullptr;
                 other.file_ = nullptr;
+                other.csv_data_buffer_ = nullptr;
             }
 
             return *this;
         }
 
         ~reader() {
-            free(buffer_);
+            std::free(buffer_);
-            free(next_line_buffer_);
+            std::free(next_line_buffer_);
-            free(helper_buffer_);
+            std::free(helper_buffer_);
 
             if (file_) {
-                fclose(file_);
+                std::fclose(file_);
             }
         }
 
@@ -698,6 +749,42 @@ private:
         reader(const reader& other) = delete;
         reader& operator=(const reader& other) = delete;
 
+        ssize_t get_line_buffer(char** lineptr, size_t* n,
+                                const char* const csv_data_buffer,
+                                size_t csv_data_size, size_t& curr_char) {
+            if (curr_char >= csv_data_size) {
+                return -1;
+            }
+
+            if (*lineptr == nullptr || *n < get_line_initial_buffer_size) {
+                auto new_lineptr = static_cast<char*>(
+                    strict_realloc(*lineptr, get_line_initial_buffer_size));
+                *lineptr = new_lineptr;
+                *n = get_line_initial_buffer_size;
+            }
+
+            size_t line_used = 0;
+            while (curr_char <= csv_data_size) {
+                if (line_used + 1 >= *n) {
+                    size_t new_n = *n * 2;
+
+                    char* new_lineptr =
+                        static_cast<char*>(strict_realloc(*lineptr, new_n));
+                    *n = new_n;
+                    *lineptr = new_lineptr;
+                }
+
+                auto c = csv_data_buffer[curr_char++];
+                (*lineptr)[line_used++] = c;
+                if (c == '\n') {
+                    (*lineptr)[line_used] = '\0';
+                    return line_used;
+                }
+            }
+
+            return (line_used != 0) ? line_used : -1;
+        }
+
         // read next line each time in order to set eof_
         bool read_next() {
             next_line_converter_.clear_error();
@@ -708,10 +795,23 @@ private:
                 if (next_line_buffer_size_ > 0) {
                     next_line_buffer_[0] = '\0';
                 }
-                ssize = get_line(&next_line_buffer_, &next_line_buffer_size_,
+
-                                 file_);
+                chars_read_ = curr_char_;
+                if (file_) {
+                    ssize = get_line_file(&next_line_buffer_,
+                                          &next_line_buffer_size_, file_);
+                    curr_char_ = std::ftell(file_);
+                } else {
+                    ssize = get_line_buffer(&next_line_buffer_,
+                                            &next_line_buffer_size_,
+                                            csv_data_buffer_, csv_data_size_,
+                                            curr_char_);
+                }
 
                 if (ssize == -1) {
+                    if (errno == ENOMEM) {
+                        throw std::bad_alloc{};
+                    }
                     return false;
                 }
 
@@ -821,6 +921,10 @@ private:
         }
 
         size_t remove_eol(char*& buffer, size_t ssize) {
+            if (buffer[ssize - 1] != '\n') {
+                return ssize;
+            }
+
             size_t size = ssize - 1;
             if (ssize >= 2 && buffer[ssize - 2] == '\r') {
                 crlf_ = true;
@@ -834,14 +938,11 @@ private:
         }
 
         void realloc_concat(char*& first, size_t& first_size,
-                            const char* const second, size_t second_size) {
+                            size_t& buffer_size, const char* const second,
-            // TODO make buffer_size an argument
+                            size_t second_size) {
-            next_line_buffer_size_ = first_size + second_size + 3;
+            buffer_size = first_size + second_size + 3;
             auto new_first = static_cast<char*>(
-                realloc(static_cast<void*>(first), next_line_buffer_size_));
+                strict_realloc(static_cast<void*>(first), buffer_size));
-            if (!first) {
-                throw std::bad_alloc{};
-            }
 
             first = new_first;
             std::copy_n(second, second_size + 1, first + first_size);
@@ -851,15 +952,25 @@ private:
         bool append_next_line_to_buffer(char*& buffer, size_t& size) {
             undo_remove_eol(buffer, size);
 
-            ssize_t next_ssize =
+            ssize_t next_ssize;
-                get_line(&helper_buffer_, &helper_size_, file_);
+            if (file_) {
+                next_ssize =
+                    get_line_file(&helper_buffer_, &helper_buffer_size, file_);
+            } else {
+                next_ssize =
+                    get_line_buffer(&helper_buffer_, &helper_buffer_size,
+                                    csv_data_buffer_, csv_data_size_,
+                                    curr_char_);
+            }
+
             if (next_ssize == -1) {
                 return false;
             }
 
             ++line_number_;
             size_t next_size = remove_eol(helper_buffer_, next_ssize);
-            realloc_concat(buffer, size, helper_buffer_, next_size);
+            realloc_concat(buffer, size, next_line_buffer_size_, helper_buffer_,
+                           next_size);
             return true;
         }
 
@@ -879,13 +990,18 @@ private:
 
         size_t buffer_size_{0};
         size_t next_line_buffer_size_{0};
-        size_t helper_size_{0};
+        size_t helper_buffer_size{0};
 
         std::string delim_;
         FILE* file_{nullptr};
 
+        const char* csv_data_buffer_{nullptr};
+        size_t csv_data_size_{0};
+        size_t curr_char_{0};
+
         bool crlf_{false};
         size_t line_number_{0};
+        size_t chars_read_{0};
 
         size_t next_line_size_{0};
     };

include/ss/setup.hpp

@@ -109,7 +109,7 @@ struct get_matcher<Matcher, T, Ts...> {
     struct is_matcher : is_instance_of_matcher<U, Matcher> {};
 
     static_assert(count_v<is_matcher, T, Ts...> <= 1,
-                  "the same matcher cannot"
+                  "the same matcher cannot "
                   "be defined multiple times");
     using type = std::conditional_t<is_matcher<T>::value, T,
                                     typename get_matcher<Matcher, Ts...>::type>;
@@ -165,25 +165,25 @@ using get_multiline_t = typename get_multiline<Ts...>::type;
 // string_error
 ////////////////
 
-class string_error;
+class string_error {};
 
 ////////////////
 // ignore_header
 ////////////////
 
-class ignore_header;
+class ignore_header {};
 
 ////////////////
 // ignore_empty
 ////////////////
 
-class ignore_empty;
+class ignore_empty {};
 
 ////////////////
 // throw_on_error
 ////////////////
 
-class throw_on_error;
+class throw_on_error {};
 
 ////////////////
 // setup implementation

include/ss/splitter.hpp

@@ -199,7 +199,7 @@ private:
     };
 
     bool match(const char* const curr, const std::string& delim) {
-        return strncmp(curr, delim.c_str(), delim.size()) == 0;
+        return std::strncmp(curr, delim.c_str(), delim.size()) == 0;
     };
 
     size_t delimiter_size(char) {

script/ci_install_lcov.sh

@@ -0,0 +1,6 @@
+#!/usr/bin/env sh
+
+echo yes | cpan DateTime Capture::Tiny
+
+wget -qO- https://github.com/linux-test-project/lcov/releases/download/v2.0/lcov-2.0.tar.gz | tar xvz
+(cd lcov-2.0 && make install)

ssp.hpp

@@ -640,15 +640,24 @@ inline void assert_throw_on_error_not_defined() {
                                  "'throw_on_error' is enabled");
 }
 
+inline void* strict_realloc(void* ptr, size_t size) {
+    ptr = std::realloc(ptr, size);
+    if (!ptr) {
+        throw std::bad_alloc{};
+    }
+
+    return ptr;
+}
+
 #if __unix__
-inline ssize_t get_line(char** lineptr, size_t* n, FILE* stream) {
+inline ssize_t get_line_file(char** lineptr, size_t* n, FILE* stream) {
     return getline(lineptr, n, stream);
 }
 #else
 
-using ssize_t = int64_t;
+using ssize_t = intptr_t;
 
-ssize_t get_line(char** lineptr, size_t* n, FILE* fp) {
+ssize_t get_line_file(char** lineptr, size_t* n, FILE* fp) {
     if (lineptr == nullptr || n == nullptr || fp == nullptr) {
         errno = EINVAL;
         return -1;
@@ -658,36 +667,24 @@ ssize_t get_line(char** lineptr, size_t* n, FILE* fp) {
 
     if (*lineptr == nullptr || *n < sizeof(buff)) {
         size_t new_n = sizeof(buff);
-        auto new_lineptr = static_cast<char*>(realloc(*lineptr, new_n));
+        *lineptr = static_cast<char*>(strict_realloc(*lineptr, new_n));
-        if (new_lineptr == nullptr) {
-            errno = ENOMEM;
-            return -1;
-        }
-
-        *lineptr = new_lineptr;
         *n = new_n;
     }
 
     (*lineptr)[0] = '\0';
 
-    while (fgets(buff, sizeof(buff), fp) != nullptr) {
+    size_t line_used = 0;
-        size_t line_used = strlen(*lineptr);
+    while (std::fgets(buff, sizeof(buff), fp) != nullptr) {
-        size_t buff_used = strlen(buff);
+        line_used = std::strlen(*lineptr);
+        size_t buff_used = std::strlen(buff);
 
         if (*n <= buff_used + line_used) {
             size_t new_n = *n * 2;
-
+            *lineptr = static_cast<char*>(strict_realloc(*lineptr, new_n));
-            auto new_lineptr = static_cast<char*>(realloc(*lineptr, new_n));
-            if (new_lineptr == nullptr) {
-                errno = ENOMEM;
-                return -1;
-            }
-
-            *lineptr = new_lineptr;
             *n = new_n;
         }
 
-        memcpy(*lineptr + line_used, buff, buff_used);
+        std::memcpy(*lineptr + line_used, buff, buff_used);
         line_used += buff_used;
         (*lineptr)[line_used] = '\0';
 
@@ -696,7 +693,7 @@ ssize_t get_line(char** lineptr, size_t* n, FILE* fp) {
         }
     }
 
-    return -1;
+    return (line_used != 0) ? line_used : -1;
 }
 
 #endif
@@ -810,7 +807,7 @@ struct get_matcher<Matcher, T, Ts...> {
     struct is_matcher : is_instance_of_matcher<U, Matcher> {};
 
     static_assert(count_v<is_matcher, T, Ts...> <= 1,
-                  "the same matcher cannot"
+                  "the same matcher cannot "
                   "be defined multiple times");
     using type = std::conditional_t<is_matcher<T>::value, T,
                                     typename get_matcher<Matcher, Ts...>::type>;
@@ -866,25 +863,25 @@ using get_multiline_t = typename get_multiline<Ts...>::type;
 // string_error
 ////////////////
 
-class string_error;
+class string_error {};
 
 ////////////////
 // ignore_header
 ////////////////
 
-class ignore_header;
+class ignore_header {};
 
 ////////////////
 // ignore_empty
 ////////////////
 
-class ignore_empty;
+class ignore_empty {};
 
 ////////////////
 // throw_on_error
 ////////////////
 
-class throw_on_error;
+class throw_on_error {};
 
 ////////////////
 // setup implementation
@@ -1185,7 +1182,7 @@ private:
     };
 
     bool match(const char* const curr, const std::string& delim) {
-        return strncmp(curr, delim.c_str(), delim.size()) == 0;
+        return std::strncmp(curr, delim.c_str(), delim.size()) == 0;
     };
 
     size_t delimiter_size(char) {
@@ -1533,6 +1530,38 @@ std::enable_if_t<std::is_floating_point_v<T>, std::optional<T>> to_num(
 
 #endif
 
+////////////////
+// numeric_wrapper
+////////////////
+
+template <typename T>
+struct numeric_wrapper {
+    using type = T;
+
+    numeric_wrapper() = default;
+    numeric_wrapper(numeric_wrapper&&) = default;
+    numeric_wrapper(const numeric_wrapper&) = default;
+
+    numeric_wrapper& operator=(numeric_wrapper&&) = default;
+    numeric_wrapper& operator=(const numeric_wrapper&) = default;
+
+    numeric_wrapper(T other) : value{other} {
+    }
+
+    operator T() {
+        return value;
+    }
+
+    operator T() const {
+        return value;
+    }
+
+    T value;
+};
+
+using int8 = numeric_wrapper<int8_t>;
+using uint8 = numeric_wrapper<uint8_t>;
+
 template <typename T>
 std::enable_if_t<std::is_integral_v<T>, std::optional<T>> to_num(
     const char* const begin, const char* const end) {
@@ -1545,6 +1574,18 @@ std::enable_if_t<std::is_integral_v<T>, std::optional<T>> to_num(
     return ret;
 }
 
+template <typename T>
+std::enable_if_t<is_instance_of_v<numeric_wrapper, T>, std::optional<T>> to_num(
+    const char* const begin, const char* const end) {
+    T ret;
+    auto [ptr, ec] = std::from_chars(begin, end, ret.value);
+
+    if (ec != std::errc() || ptr != end) {
+        return std::nullopt;
+    }
+    return ret;
+}
+
 ////////////////
 // extract
 ////////////////
@@ -1559,7 +1600,8 @@ struct unsupported_type {
 template <typename T>
 std::enable_if_t<!std::is_integral_v<T> && !std::is_floating_point_v<T> &&
                      !is_instance_of_v<std::optional, T> &&
-                     !is_instance_of_v<std::variant, T>,
+                     !is_instance_of_v<std::variant, T> &&
+                     !is_instance_of_v<numeric_wrapper, T>,
                  bool>
 extract(const char*, const char*, T&) {
     static_assert(error::unsupported_type<T>::value,
@@ -1568,7 +1610,9 @@ extract(const char*, const char*, T&) {
 }
 
 template <typename T>
-std::enable_if_t<std::is_integral_v<T> || std::is_floating_point_v<T>, bool>
+std::enable_if_t<std::is_integral_v<T> || std::is_floating_point_v<T> ||
+                     is_instance_of_v<numeric_wrapper, T>,
+                 bool>
 extract(const char* begin, const char* end, T& value) {
     auto optional_value = to_num<T>(begin, end);
     if (!optional_value) {
@@ -1625,9 +1669,9 @@ inline bool extract(const char* begin, const char* end, bool& value) {
         }
     } else {
         size_t size = end - begin;
-        if (size == 4 && strncmp(begin, "true", size) == 0) {
+        if (size == 4 && std::strncmp(begin, "true", size) == 0) {
             value = true;
-        } else if (size == 5 && strncmp(begin, "false", size) == 0) {
+        } else if (size == 5 && std::strncmp(begin, "false", size) == 0) {
             value = false;
         } else {
             return false;
@@ -2181,6 +2225,23 @@ public:
         }
     }
 
+    parser(const char* const csv_data_buffer, size_t csv_data_size,
+           const std::string& delim = ss::default_delimiter)
+        : file_name_{"buffer line"},
+          reader_{csv_data_buffer, csv_data_size, delim} {
+        if (csv_data_buffer) {
+            read_line();
+            if constexpr (ignore_header) {
+                ignore_next();
+            } else {
+                raw_header_ = reader_.get_buffer();
+            }
+        } else {
+            handle_error_null_buffer();
+            eof_ = true;
+        }
+    }
+
     parser(parser&& other) = default;
     parser& operator=(parser&& other) = default;
 
@@ -2217,10 +2278,14 @@ public:
     }
 
     size_t line() const {
-        return reader_.line_number_ > 1 ? reader_.line_number_ - 1
+        return reader_.line_number_ > 0 ? reader_.line_number_ - 1
                                         : reader_.line_number_;
     }
 
+    size_t position() const {
+        return reader_.chars_read_;
+    }
+
     template <typename T, typename... Ts>
     no_void_validator_tup_t<T, Ts...> get_next() {
         std::optional<std::string> error;
@@ -2325,7 +2390,7 @@ public:
         reader_.next_line_converter_.set_column_mapping(column_mappings,
                                                         header_.size());
 
-        if (line() == 1) {
+        if (line() == 0) {
             ignore_next();
         }
     }
@@ -2484,7 +2549,10 @@ public:
 
         template <typename U, typename... Us, typename Fun = none>
         void try_convert_and_invoke(std::optional<U>& value, Fun&& fun) {
-            if (!parser_.valid()) {
+            if (parser_.valid()) {
+                return;
+            }
+
             auto tuple_output = try_same<Us...>();
             if (!parser_.valid()) {
                 return;
@@ -2498,7 +2566,6 @@ public:
 
             parser_.try_invoke(*value, std::forward<Fun>(fun));
         }
-        }
 
         template <typename U, typename... Us>
         no_void_validator_tup_t<U, Us...> try_same() {
@@ -2645,6 +2712,19 @@ private:
         }
     }
 
+    void handle_error_null_buffer() {
+        constexpr static auto error_msg = " received null data buffer";
+
+        if constexpr (string_error) {
+            error_.clear();
+            error_.append(file_name_).append(error_msg);
+        } else if constexpr (throw_on_error) {
+            throw ss::exception{file_name_ + error_msg};
+        } else {
+            error_ = true;
+        }
+    }
+
     void handle_error_file_not_open() {
         constexpr static auto error_msg = " could not be opened";
 
@@ -2771,21 +2851,30 @@ private:
 
     struct reader {
         reader(const std::string& file_name_, const std::string& delim)
-            : delim_{delim}, file_{fopen(file_name_.c_str(), "rb")} {
+            : delim_{delim}, file_{std::fopen(file_name_.c_str(), "rb")} {
+        }
+
+        reader(const char* const buffer, size_t csv_data_size,
+               const std::string& delim)
+            : delim_{delim}, csv_data_buffer_{buffer},
+              csv_data_size_{csv_data_size} {
         }
 
         reader(reader&& other)
             : buffer_{other.buffer_},
               next_line_buffer_{other.next_line_buffer_},
-              helper_buffer_{other.helper_buffer_}, converter_{std::move(
+              helper_buffer_{other.helper_buffer_},
-                                                        other.converter_)},
+              converter_{std::move(other.converter_)},
               next_line_converter_{std::move(other.next_line_converter_)},
               buffer_size_{other.buffer_size_},
               next_line_buffer_size_{other.next_line_buffer_size_},
-              helper_size_{other.helper_size_}, delim_{std::move(other.delim_)},
+              helper_buffer_size{other.helper_buffer_size},
-              file_{other.file_}, crlf_{other.crlf_},
+              delim_{std::move(other.delim_)}, file_{other.file_},
-              line_number_{other.line_number_}, next_line_size_{
+              csv_data_buffer_{other.csv_data_buffer_},
-                                                    other.next_line_size_} {
+              csv_data_size_{other.csv_data_size_},
+              curr_char_{other.curr_char_}, crlf_{other.crlf_},
+              line_number_{other.line_number_}, chars_read_{other.chars_read_},
+              next_line_size_{other.next_line_size_} {
             other.buffer_ = nullptr;
             other.next_line_buffer_ = nullptr;
             other.helper_buffer_ = nullptr;
@@ -2801,29 +2890,34 @@ private:
                 next_line_converter_ = std::move(other.next_line_converter_);
                 buffer_size_ = other.buffer_size_;
                 next_line_buffer_size_ = other.next_line_buffer_size_;
-                helper_size_ = other.helper_size_;
+                helper_buffer_size = other.helper_buffer_size;
                 delim_ = std::move(other.delim_);
                 file_ = other.file_;
+                csv_data_buffer_ = other.csv_data_buffer_;
+                csv_data_size_ = other.csv_data_size_;
+                curr_char_ = other.curr_char_;
                 crlf_ = other.crlf_;
                 line_number_ = other.line_number_;
+                chars_read_ = other.chars_read_;
                 next_line_size_ = other.next_line_size_;
 
                 other.buffer_ = nullptr;
                 other.next_line_buffer_ = nullptr;
                 other.helper_buffer_ = nullptr;
                 other.file_ = nullptr;
+                other.csv_data_buffer_ = nullptr;
             }
 
             return *this;
         }
 
         ~reader() {
-            free(buffer_);
+            std::free(buffer_);
-            free(next_line_buffer_);
+            std::free(next_line_buffer_);
-            free(helper_buffer_);
+            std::free(helper_buffer_);
 
             if (file_) {
-                fclose(file_);
+                std::fclose(file_);
             }
         }
 
@@ -2831,6 +2925,42 @@ private:
         reader(const reader& other) = delete;
         reader& operator=(const reader& other) = delete;
 
+        ssize_t get_line_buffer(char** lineptr, size_t* n,
+                                const char* const csv_data_buffer,
+                                size_t csv_data_size, size_t& curr_char) {
+            if (curr_char >= csv_data_size) {
+                return -1;
+            }
+
+            if (*lineptr == nullptr || *n < get_line_initial_buffer_size) {
+                auto new_lineptr = static_cast<char*>(
+                    strict_realloc(*lineptr, get_line_initial_buffer_size));
+                *lineptr = new_lineptr;
+                *n = get_line_initial_buffer_size;
+            }
+
+            size_t line_used = 0;
+            while (curr_char <= csv_data_size) {
+                if (line_used + 1 >= *n) {
+                    size_t new_n = *n * 2;
+
+                    char* new_lineptr =
+                        static_cast<char*>(strict_realloc(*lineptr, new_n));
+                    *n = new_n;
+                    *lineptr = new_lineptr;
+                }
+
+                auto c = csv_data_buffer[curr_char++];
+                (*lineptr)[line_used++] = c;
+                if (c == '\n') {
+                    (*lineptr)[line_used] = '\0';
+                    return line_used;
+                }
+            }
+
+            return (line_used != 0) ? line_used : -1;
+        }
+
         // read next line each time in order to set eof_
         bool read_next() {
             next_line_converter_.clear_error();
@@ -2841,10 +2971,23 @@ private:
                 if (next_line_buffer_size_ > 0) {
                     next_line_buffer_[0] = '\0';
                 }
-                ssize = get_line(&next_line_buffer_, &next_line_buffer_size_,
+
-                                 file_);
+                chars_read_ = curr_char_;
+                if (file_) {
+                    ssize = get_line_file(&next_line_buffer_,
+                                          &next_line_buffer_size_, file_);
+                    curr_char_ = std::ftell(file_);
+                } else {
+                    ssize = get_line_buffer(&next_line_buffer_,
+                                            &next_line_buffer_size_,
+                                            csv_data_buffer_, csv_data_size_,
+                                            curr_char_);
+                }
 
                 if (ssize == -1) {
+                    if (errno == ENOMEM) {
+                        throw std::bad_alloc{};
+                    }
                     return false;
                 }
 
@@ -2954,6 +3097,10 @@ private:
         }
 
         size_t remove_eol(char*& buffer, size_t ssize) {
+            if (buffer[ssize - 1] != '\n') {
+                return ssize;
+            }
+
             size_t size = ssize - 1;
             if (ssize >= 2 && buffer[ssize - 2] == '\r') {
                 crlf_ = true;
@@ -2967,14 +3114,11 @@ private:
         }
 
         void realloc_concat(char*& first, size_t& first_size,
-                            const char* const second, size_t second_size) {
+                            size_t& buffer_size, const char* const second,
-            // TODO make buffer_size an argument
+                            size_t second_size) {
-            next_line_buffer_size_ = first_size + second_size + 3;
+            buffer_size = first_size + second_size + 3;
             auto new_first = static_cast<char*>(
-                realloc(static_cast<void*>(first), next_line_buffer_size_));
+                strict_realloc(static_cast<void*>(first), buffer_size));
-            if (!first) {
-                throw std::bad_alloc{};
-            }
 
             first = new_first;
             std::copy_n(second, second_size + 1, first + first_size);
@@ -2984,15 +3128,25 @@ private:
         bool append_next_line_to_buffer(char*& buffer, size_t& size) {
             undo_remove_eol(buffer, size);
 
-            ssize_t next_ssize =
+            ssize_t next_ssize;
-                get_line(&helper_buffer_, &helper_size_, file_);
+            if (file_) {
+                next_ssize =
+                    get_line_file(&helper_buffer_, &helper_buffer_size, file_);
+            } else {
+                next_ssize =
+                    get_line_buffer(&helper_buffer_, &helper_buffer_size,
+                                    csv_data_buffer_, csv_data_size_,
+                                    curr_char_);
+            }
+
             if (next_ssize == -1) {
                 return false;
             }
 
             ++line_number_;
             size_t next_size = remove_eol(helper_buffer_, next_ssize);
-            realloc_concat(buffer, size, helper_buffer_, next_size);
+            realloc_concat(buffer, size, next_line_buffer_size_, helper_buffer_,
+                           next_size);
             return true;
         }
 
@@ -3012,13 +3166,18 @@ private:
 
         size_t buffer_size_{0};
         size_t next_line_buffer_size_{0};
-        size_t helper_size_{0};
+        size_t helper_buffer_size{0};
 
         std::string delim_;
         FILE* file_{nullptr};
 
+        const char* csv_data_buffer_{nullptr};
+        size_t csv_data_size_{0};
+        size_t curr_char_{0};
+
         bool crlf_{false};
         size_t line_number_{0};
+        size_t chars_read_{0};
 
         size_t next_line_size_{0};
     };

test/CMakeLists.txt

@@ -32,9 +32,11 @@ set(DOCTEST "${FETCHCONTENT_BASE_DIR}/doctest-src")
 
 enable_testing()
 
-foreach(name IN ITEMS test_splitter test_parser test_converter test_extractions
+foreach(name IN ITEMS test_splitter test_parser1_1 test_parser1_2
-                      test_parser2_1 test_parser2_2 test_parser2_3
+                      test_parser1_3 test_parser1_4 test_converter
-                      test_parser2_4 test_extractions_without_fast_float)
+                      test_extractions test_parser2_1 test_parser2_2
+                      test_parser2_3 test_parser2_4 test_parser2_5
+                      test_parser2_6 test_extractions_without_fast_float)
     add_executable("${name}" "${name}.cpp")
     target_link_libraries("${name}" PRIVATE ssp::ssp fast_float
                                             doctest::doctest)

test/meson.build

@@ -2,7 +2,10 @@ doctest_dep = dependency('doctest')
 add_project_arguments('-DDOCTEST_CONFIG_IMPLEMENT_WITH_MAIN', language: 'cpp')
 
 tests = [
-  'parser',
+  'parser1_1',
+  'parser1_2',
+  'parser1_3',
+  'parser1_4',
   'splitter',
   'converter',
   'extractions',
@@ -10,6 +13,8 @@ tests = [
   'parser2_2',
   'parser2_3',
   'parser2_4',
+  'parser2_5',
+  'parser2_6',
   'extractions_without_fast_float',
 ]
 

test/test_converter.cpp

@@ -46,90 +46,88 @@ TEST_CASE("converter test split with exceptions") {
     }
 }
 
-TEST_CASE("converter test valid conversions") {
+TEST_CASE_TEMPLATE("converter test valid conversions", T, int, ss::uint8) {
     ss::converter c;
 
     {
-        auto tup = c.convert<int>("5");
+        auto tup = c.convert<T>("5");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 5);
     }
     {
-        auto tup = c.convert<int, void>("5,junk");
+        auto tup = c.convert<T, void>("5,junk");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 5);
     }
     {
-        auto tup = c.convert<void, int>("junk,5");
+        auto tup = c.convert<void, T>("junk,5");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 5);
     }
     {
-        auto tup = c.convert<int, void, void>("5\njunk\njunk", "\n");
+        auto tup = c.convert<T, void, void>("5\njunk\njunk", "\n");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 5);
     }
     {
-        auto tup = c.convert<void, int, void>("junk 5 junk", " ");
+        auto tup = c.convert<void, T, void>("junk 5 junk", " ");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 5);
     }
     {
-        auto tup = c.convert<void, void, int>("junk\tjunk\t5", "\t");
+        auto tup = c.convert<void, void, T>("junk\tjunk\t5", "\t");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 5);
     }
     {
         auto tup =
-            c.convert<void, void, std::optional<int>>("junk\tjunk\t5", "\t");
+            c.convert<void, void, std::optional<T>>("junk\tjunk\t5", "\t");
         REQUIRE(c.valid());
         REQUIRE(tup.has_value());
         CHECK_EQ(tup, 5);
     }
     {
-        auto tup = c.convert<int, double, void>("5,6.6,junk");
+        auto tup = c.convert<T, double, void>("5,6.6,junk");
         REQUIRE(c.valid());
         CHECK_EQ(tup, std::make_tuple(5, 6.6));
     }
     {
-        auto tup = c.convert<int, void, double>("5,junk,6.6");
+        auto tup = c.convert<T, void, double>("5,junk,6.6");
         REQUIRE(c.valid());
         CHECK_EQ(tup, std::make_tuple(5, 6.6));
     }
     {
-        auto tup = c.convert<void, int, double>("junk;5;6.6", ";");
+        auto tup = c.convert<void, T, double>("junk;5;6.6", ";");
         REQUIRE(c.valid());
         CHECK_EQ(tup, std::make_tuple(5, 6.6));
     }
     {
-        auto tup =
+        auto tup = c.convert<void, std::optional<T>, double>("junk;5;6.6", ";");
-            c.convert<void, std::optional<int>, double>("junk;5;6.6", ";");
         REQUIRE(c.valid());
         REQUIRE(std::get<0>(tup).has_value());
         CHECK_EQ(tup, std::make_tuple(5, 6.6));
     }
     {
         auto tup =
-            c.convert<void, std::optional<int>, double>("junk;5.4;6.6", ";");
+            c.convert<void, std::optional<T>, double>("junk;5.4;6.6", ";");
         REQUIRE(c.valid());
         REQUIRE_FALSE(std::get<0>(tup).has_value());
-        CHECK_EQ(tup, std::make_tuple(std::optional<int>{}, 6.6));
+        CHECK_EQ(tup, std::make_tuple(std::optional<T>{}, 6.6));
     }
     {
         auto tup =
-            c.convert<void, std::variant<int, double>, double>("junk;5;6.6",
+            c.convert<void, std::variant<T, double>, double>("junk;5;6.6", ";");
-                                                               ";");
         REQUIRE(c.valid());
-        REQUIRE(std::holds_alternative<int>(std::get<0>(tup)));
+        REQUIRE(std::holds_alternative<T>(std::get<0>(tup)));
-        CHECK_EQ(tup, std::make_tuple(std::variant<int, double>{5}, 6.6));
+        CHECK_EQ(tup, std::make_tuple(std::variant<T, double>{T(5)}, 6.6));
     }
     {
         auto tup =
-            c.convert<void, std::variant<int, double>, double>("junk;5.5;6.6",
+            c.convert<void, std::variant<T, double>, double>("junk;5.5;6.6",
                                                              ";");
         REQUIRE(c.valid());
         REQUIRE(std::holds_alternative<double>(std::get<0>(tup)));
-        CHECK_EQ(tup, std::make_tuple(std::variant<int, double>{5.5}, 6.6));
+        CHECK_EQ(tup, std::make_tuple(std::variant<T, double>{5.5}, 6.6));
     }
     {
         auto tup = c.convert<void, std::string_view, double,
@@ -140,11 +138,12 @@ TEST_CASE("converter test valid conversions") {
     }
 }
 
-TEST_CASE("converter test valid conversions with exceptions") {
+TEST_CASE_TEMPLATE("converter test valid conversions with exceptions", T, int,
+                   ss::uint8) {
     ss::converter<ss::throw_on_error> c;
 
     try {
-        auto tup = c.convert<int>("5");
+        auto tup = c.convert<T>("5");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 5);
     } catch (ss::exception& e) {
@@ -152,7 +151,7 @@ TEST_CASE("converter test valid conversions with exceptions") {
     }
 
     try {
-        auto tup = c.convert<int, void>("5,junk");
+        auto tup = c.convert<T, void>("5,junk");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 5);
     } catch (ss::exception& e) {
@@ -160,7 +159,7 @@ TEST_CASE("converter test valid conversions with exceptions") {
     }
 
     try {
-        auto tup = c.convert<void, int>("junk,5");
+        auto tup = c.convert<void, T>("junk,5");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 5);
     } catch (ss::exception& e) {
@@ -168,7 +167,7 @@ TEST_CASE("converter test valid conversions with exceptions") {
     }
 
     try {
-        auto tup = c.convert<int, void, void>("5\njunk\njunk", "\n");
+        auto tup = c.convert<T, void, void>("5\njunk\njunk", "\n");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 5);
     } catch (ss::exception& e) {
@@ -176,7 +175,7 @@ TEST_CASE("converter test valid conversions with exceptions") {
     }
 
     try {
-        auto tup = c.convert<void, int, void>("junk 5 junk", " ");
+        auto tup = c.convert<void, T, void>("junk 5 junk", " ");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 5);
     } catch (ss::exception& e) {
@@ -184,7 +183,7 @@ TEST_CASE("converter test valid conversions with exceptions") {
     }
 
     try {
-        auto tup = c.convert<void, void, int>("junk\tjunk\t5", "\t");
+        auto tup = c.convert<void, void, T>("junk\tjunk\t5", "\t");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 5);
     } catch (ss::exception& e) {
@@ -193,7 +192,7 @@ TEST_CASE("converter test valid conversions with exceptions") {
 
     try {
         auto tup =
-            c.convert<void, void, std::optional<int>>("junk\tjunk\t5", "\t");
+            c.convert<void, void, std::optional<T>>("junk\tjunk\t5", "\t");
         REQUIRE(c.valid());
         REQUIRE(tup.has_value());
         CHECK_EQ(tup, 5);
@@ -202,7 +201,7 @@ TEST_CASE("converter test valid conversions with exceptions") {
     }
 
     try {
-        auto tup = c.convert<int, double, void>("5,6.6,junk");
+        auto tup = c.convert<T, double, void>("5,6.6,junk");
         REQUIRE(c.valid());
         CHECK_EQ(tup, std::make_tuple(5, 6.6));
     } catch (ss::exception& e) {
@@ -210,7 +209,7 @@ TEST_CASE("converter test valid conversions with exceptions") {
     }
 
     try {
-        auto tup = c.convert<int, void, double>("5,junk,6.6");
+        auto tup = c.convert<T, void, double>("5,junk,6.6");
         REQUIRE(c.valid());
         CHECK_EQ(tup, std::make_tuple(5, 6.6));
     } catch (ss::exception& e) {
@@ -218,7 +217,7 @@ TEST_CASE("converter test valid conversions with exceptions") {
     }
 
     try {
-        auto tup = c.convert<void, int, double>("junk;5;6.6", ";");
+        auto tup = c.convert<void, T, double>("junk;5;6.6", ";");
         REQUIRE(c.valid());
         CHECK_EQ(tup, std::make_tuple(5, 6.6));
     } catch (ss::exception& e) {
@@ -226,8 +225,7 @@ TEST_CASE("converter test valid conversions with exceptions") {
     }
 
     try {
-        auto tup =
+        auto tup = c.convert<void, std::optional<T>, double>("junk;5;6.6", ";");
-            c.convert<void, std::optional<int>, double>("junk;5;6.6", ";");
         REQUIRE(c.valid());
         REQUIRE(std::get<0>(tup).has_value());
         CHECK_EQ(tup, std::make_tuple(5, 6.6));
@@ -237,32 +235,31 @@ TEST_CASE("converter test valid conversions with exceptions") {
 
     try {
         auto tup =
-            c.convert<void, std::optional<int>, double>("junk;5.4;6.6", ";");
+            c.convert<void, std::optional<T>, double>("junk;5.4;6.6", ";");
         REQUIRE(c.valid());
         REQUIRE_FALSE(std::get<0>(tup).has_value());
-        CHECK_EQ(tup, std::make_tuple(std::optional<int>{}, 6.6));
+        CHECK_EQ(tup, std::make_tuple(std::optional<T>{}, 6.6));
     } catch (ss::exception& e) {
         FAIL(std::string{e.what()});
     }
 
     try {
         auto tup =
-            c.convert<void, std::variant<int, double>, double>("junk;5;6.6",
+            c.convert<void, std::variant<T, double>, double>("junk;5;6.6", ";");
-                                                               ";");
         REQUIRE(c.valid());
-        REQUIRE(std::holds_alternative<int>(std::get<0>(tup)));
+        REQUIRE(std::holds_alternative<T>(std::get<0>(tup)));
-        CHECK_EQ(tup, std::make_tuple(std::variant<int, double>{5}, 6.6));
+        CHECK_EQ(tup, std::make_tuple(std::variant<T, double>{T(5)}, 6.6));
     } catch (ss::exception& e) {
         FAIL(std::string{e.what()});
     }
 
     try {
         auto tup =
-            c.convert<void, std::variant<int, double>, double>("junk;5.5;6.6",
+            c.convert<void, std::variant<T, double>, double>("junk;5.5;6.6",
                                                              ";");
         REQUIRE(c.valid());
         REQUIRE(std::holds_alternative<double>(std::get<0>(tup)));
-        CHECK_EQ(tup, std::make_tuple(std::variant<int, double>{5.5}, 6.6));
+        CHECK_EQ(tup, std::make_tuple(std::variant<T, double>{5.5}, 6.6));
     } catch (ss::exception& e) {
         FAIL(std::string{e.what()});
     }
@@ -278,110 +275,114 @@ TEST_CASE("converter test valid conversions with exceptions") {
     }
 }
 
-TEST_CASE("converter test invalid conversions") {
+TEST_CASE_TEMPLATE("converter test invalid conversions", T, int, ss::uint8) {
     ss::converter c;
 
-    c.convert<int>("");
+    c.convert<T>("");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<int>("1", "");
+    c.convert<T>("1", "");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<int>("10", "");
+    c.convert<T>("10", "");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<int, void>("");
+    c.convert<T, void>("");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<int, void>(",junk");
+    c.convert<T, void>(",junk");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<void, int>("junk,");
+    c.convert<void, T>("junk,");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<int>("x");
+    c.convert<T>("x");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<int, void>("x");
+    c.convert<T, void>("x");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<int, void>("x,junk");
+    c.convert<T, void>("x,junk");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<void, int>("junk,x");
+    c.convert<void, T>("junk,x");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<void, std::variant<int, double>, double>("junk;.5.5;6", ";");
+    c.convert<void, std::variant<T, double>, double>("junk;.5.5;6", ";");
     REQUIRE_FALSE(c.valid());
 }
 
-TEST_CASE("converter test invalid conversions with exceptions") {
+TEST_CASE_TEMPLATE("converter test invalid conversions with exceptions", T, int,
+                   ss::uint8) {
     ss::converter<ss::throw_on_error> c;
 
-    REQUIRE_EXCEPTION(c.convert<int>(""));
+    REQUIRE_EXCEPTION(c.convert<T>(""));
-    REQUIRE_EXCEPTION(c.convert<int>("1", ""));
+    REQUIRE_EXCEPTION(c.convert<T>("1", ""));
-    REQUIRE_EXCEPTION(c.convert<int>("10", ""));
+    REQUIRE_EXCEPTION(c.convert<T>("10", ""));
-    REQUIRE_EXCEPTION(c.convert<int, void>(""));
+    REQUIRE_EXCEPTION(c.convert<T, void>(""));
-    REQUIRE_EXCEPTION(c.convert<int, void>(",junk"));
+    REQUIRE_EXCEPTION(c.convert<T, void>(",junk"));
-    REQUIRE_EXCEPTION(c.convert<void, int>("junk,"));
+    REQUIRE_EXCEPTION(c.convert<void, T>("junk,"));
-    REQUIRE_EXCEPTION(c.convert<int>("x"));
+    REQUIRE_EXCEPTION(c.convert<T>("x"));
-    REQUIRE_EXCEPTION(c.convert<int, void>("x"));
+    REQUIRE_EXCEPTION(c.convert<T, void>("x"));
-    REQUIRE_EXCEPTION(c.convert<int, void>("x,junk"));
+    REQUIRE_EXCEPTION(c.convert<T, void>("x,junk"));
-    REQUIRE_EXCEPTION(c.convert<void, int>("junk,x"));
+    REQUIRE_EXCEPTION(c.convert<void, T>("junk,x"));
     REQUIRE_EXCEPTION(
-        c.convert<void, std::variant<int, double>, double>("junk;.5.5;6", ";"));
+        c.convert<void, std::variant<T, double>, double>("junk;.5.5;6", ";"));
 }
 
-TEST_CASE("converter test ss:ax restriction (all except)") {
+TEST_CASE_TEMPLATE("converter test ss:ax restriction (all except)", T, int,
+                   ss::uint8) {
     ss::converter c;
 
-    c.convert<ss::ax<int, 0>>("0");
+    c.convert<ss::ax<T, 0>>("0");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<ss::ax<int, 0, 1, 2>>("1");
+    c.convert<ss::ax<T, 0, 1, 2>>("1");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<void, char, ss::ax<int, 0, 1, 2>>("junk,c,1");
+    c.convert<void, char, ss::ax<T, 0, 1, 2>>("junk,c,1");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<ss::ax<int, 1>, char>("1,c");
+    c.convert<ss::ax<T, 1>, char>("1,c");
     REQUIRE_FALSE(c.valid());
     {
-        int tup = c.convert<ss::ax<int, 1>>("3");
+        T tup = c.convert<ss::ax<T, 1>>("3");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 3);
     }
     {
-        std::tuple<char, int> tup = c.convert<char, ss::ax<int, 1>>("c,3");
+        std::tuple<char, T> tup = c.convert<char, ss::ax<T, 1>>("c,3");
         REQUIRE(c.valid());
         CHECK_EQ(tup, std::make_tuple('c', 3));
     }
     {
-        std::tuple<int, char> tup = c.convert<ss::ax<int, 1>, char>("3,c");
+        std::tuple<T, char> tup = c.convert<ss::ax<T, 1>, char>("3,c");
         REQUIRE(c.valid());
         CHECK_EQ(tup, std::make_tuple(3, 'c'));
     }
 }
 
-TEST_CASE("converter test ss:ax restriction (all except) with exceptions") {
+TEST_CASE_TEMPLATE(
+    "converter test ss:ax restriction (all except) with exceptions", T, int,
+    ss::uint8) {
     ss::converter<ss::throw_on_error> c;
 
-    REQUIRE_EXCEPTION(c.convert<ss::ax<int, 0>>("0"));
+    REQUIRE_EXCEPTION(c.convert<ss::ax<T, 0>>("0"));
-    REQUIRE_EXCEPTION(c.convert<ss::ax<int, 0, 1, 2>>("1"));
+    REQUIRE_EXCEPTION(c.convert<ss::ax<T, 0, 1, 2>>("1"));
-    REQUIRE_EXCEPTION(c.convert<void, char, ss::ax<int, 0, 1, 2>>("junk,c,1"));
+    REQUIRE_EXCEPTION(c.convert<void, char, ss::ax<T, 0, 1, 2>>("junk,c,1"));
-    REQUIRE_EXCEPTION(c.convert<ss::ax<int, 1>, char>("1,c"));
+    REQUIRE_EXCEPTION(c.convert<ss::ax<T, 1>, char>("1,c"));
 
     try {
         {
-            int tup = c.convert<ss::ax<int, 1>>("3");
+            T tup = c.convert<ss::ax<T, 1>>("3");
             CHECK_EQ(tup, 3);
         }
         {
-            std::tuple<char, int> tup = c.convert<char, ss::ax<int, 1>>("c,3");
+            std::tuple<char, T> tup = c.convert<char, ss::ax<T, 1>>("c,3");
             CHECK_EQ(tup, std::make_tuple('c', 3));
         }
         {
-            std::tuple<int, char> tup = c.convert<ss::ax<int, 1>, char>("3,c");
+            std::tuple<T, char> tup = c.convert<ss::ax<T, 1>, char>("3,c");
             CHECK_EQ(tup, std::make_tuple(3, 'c'));
         }
     } catch (ss::exception& e) {
@@ -456,65 +457,68 @@ TEST_CASE("converter test ss:nx restriction (none except) with exceptions") {
     }
 }
 
-TEST_CASE("converter test ss:ir restriction (in range)") {
+TEST_CASE_TEMPLATE("converter test ss:ir restriction (in range)", T, int,
+                   ss::uint8) {
     ss::converter c;
 
-    c.convert<ss::ir<int, 0, 2>>("3");
+    c.convert<ss::ir<T, 0, 2>>("3");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<char, ss::ir<int, 4, 69>>("c,3");
+    c.convert<char, ss::ir<T, 4, 69>>("c,3");
     REQUIRE_FALSE(c.valid());
 
-    c.convert<ss::ir<int, 1, 2>, char>("3,c");
+    c.convert<ss::ir<T, 1, 2>, char>("3,c");
     REQUIRE_FALSE(c.valid());
 
     {
-        auto tup = c.convert<ss::ir<int, 1, 5>>("3");
+        auto tup = c.convert<ss::ir<T, 1, 5>>("3");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 3);
     }
     {
-        auto tup = c.convert<ss::ir<int, 0, 2>>("2");
+        auto tup = c.convert<ss::ir<T, 0, 2>>("2");
         REQUIRE(c.valid());
         CHECK_EQ(tup, 2);
     }
     {
-        auto tup = c.convert<char, void, ss::ir<int, 0, 1>>("c,junk,1");
+        auto tup = c.convert<char, void, ss::ir<T, 0, 1>>("c,junk,1");
         REQUIRE(c.valid());
         CHECK_EQ(tup, std::make_tuple('c', 1));
     }
     {
-        auto tup = c.convert<ss::ir<int, 1, 20>, char>("1,c");
+        auto tup = c.convert<ss::ir<T, 1, 20>, char>("1,c");
         REQUIRE(c.valid());
         CHECK_EQ(tup, std::make_tuple(1, 'c'));
     }
 }
 
-TEST_CASE("converter test ss:ir restriction (in range) with exceptions") {
+TEST_CASE_TEMPLATE(
+    "converter test ss:ir restriction (in range) with exceptions", T, int,
+    ss::uint8) {
     ss::converter<ss::throw_on_error> c;
 
-    REQUIRE_EXCEPTION(c.convert<ss::ir<int, 0, 2>>("3"));
+    REQUIRE_EXCEPTION(c.convert<ss::ir<T, 0, 2>>("3"));
-    REQUIRE_EXCEPTION(c.convert<char, ss::ir<int, 4, 69>>("c,3"));
+    REQUIRE_EXCEPTION(c.convert<char, ss::ir<T, 4, 69>>("c,3"));
-    REQUIRE_EXCEPTION(c.convert<ss::ir<int, 1, 2>, char>("3,c"));
+    REQUIRE_EXCEPTION(c.convert<ss::ir<T, 1, 2>, char>("3,c"));
 
     try {
         {
-            auto tup = c.convert<ss::ir<int, 1, 5>>("3");
+            auto tup = c.convert<ss::ir<T, 1, 5>>("3");
             REQUIRE(c.valid());
             CHECK_EQ(tup, 3);
         }
         {
-            auto tup = c.convert<ss::ir<int, 0, 2>>("2");
+            auto tup = c.convert<ss::ir<T, 0, 2>>("2");
             REQUIRE(c.valid());
             CHECK_EQ(tup, 2);
         }
         {
-            auto tup = c.convert<char, void, ss::ir<int, 0, 1>>("c,junk,1");
+            auto tup = c.convert<char, void, ss::ir<T, 0, 1>>("c,junk,1");
             REQUIRE(c.valid());
             CHECK_EQ(tup, std::make_tuple('c', 1));
         }
         {
-            auto tup = c.convert<ss::ir<int, 1, 20>, char>("1,c");
+            auto tup = c.convert<ss::ir<T, 1, 20>, char>("1,c");
             REQUIRE(c.valid());
             CHECK_EQ(tup, std::make_tuple(1, 'c'));
         }
@@ -978,4 +982,3 @@ TEST_CASE("converter test invalid split conversions with exceptions") {
         buff(R"(just,some,2,"strings\")")));
     CHECK(c.unterminated_quote());
 }
-

test/test_extractions.cpp

@@ -2,6 +2,32 @@
 #include <algorithm>
 #include <ss/extract.hpp>
 
+namespace {
+
+template <typename T>
+struct numeric_limits : public std::numeric_limits<T> {};
+
+template <typename T>
+struct numeric_limits<ss::numeric_wrapper<T>> : public std::numeric_limits<T> {
+};
+
+template <typename T>
+struct is_signed : public std::is_signed<T> {};
+
+template <>
+struct is_signed<ss::int8> : public std::true_type {};
+
+template <typename T>
+struct is_unsigned : public std::is_unsigned<T> {};
+
+template <>
+struct is_unsigned<ss::uint8> : public std::true_type {};
+
+} /* namespace */
+
+static_assert(is_signed<ss::int8>::value);
+static_assert(is_unsigned<ss::uint8>::value);
+
 TEST_CASE("testing extract functions for floating point values") {
     CHECK_FLOATING_CONVERSION(123.456, float);
     CHECK_FLOATING_CONVERSION(123.456, double);
@@ -22,18 +48,18 @@ TEST_CASE("testing extract functions for floating point values") {
 #define CHECK_DECIMAL_CONVERSION(input, type)                                  \
     {                                                                          \
         std::string s = #input;                                                \
-        auto t = ss::to_num<type>(s.c_str(), s.c_str() + s.size());            \
+        type value;                                                            \
-        REQUIRE(t.has_value());                                                \
+        bool valid = ss::extract(s.c_str(), s.c_str() + s.size(), value);      \
-        CHECK_EQ(t.value(), type(input));                                      \
+        REQUIRE(valid);                                                        \
+        CHECK_EQ(value, type(input));                                          \
     }                                                                          \
-    {                                                                          \
     /* check negative too */                                                   \
-        if (std::is_signed_v<type>) {                                          \
+    if (is_signed<type>::value) {                                              \
-            auto s = std::string("-") + #input;                                \
+        std::string s = std::string("-") + #input;                             \
-            auto t = ss::to_num<type>(s.c_str(), s.c_str() + s.size());        \
+        type value;                                                            \
-            REQUIRE(t.has_value());                                            \
+        bool valid = ss::extract(s.c_str(), s.c_str() + s.size(), value);      \
-            CHECK_EQ(t.value(), type(-input));                                 \
+        REQUIRE(valid);                                                        \
-        }                                                                      \
+        CHECK_EQ(value, type(-input));                                         \
     }
 
 using us = unsigned short;
@@ -43,6 +69,8 @@ using ll = long long;
 using ull = unsigned long long;
 
 TEST_CASE("extract test functions for decimal values") {
+    CHECK_DECIMAL_CONVERSION(12, ss::int8);
+    CHECK_DECIMAL_CONVERSION(12, ss::uint8);
     CHECK_DECIMAL_CONVERSION(1234, short);
     CHECK_DECIMAL_CONVERSION(1234, us);
     CHECK_DECIMAL_CONVERSION(1234, int);
@@ -54,6 +82,9 @@ TEST_CASE("extract test functions for decimal values") {
 }
 
 TEST_CASE("extract test functions for numbers with invalid inputs") {
+    // negative unsigned value for numeric_wrapper
+    CHECK_INVALID_CONVERSION("-12", ss::uint8);
+
     // negative unsigned value
     CHECK_INVALID_CONVERSION("-1234", ul);
 
@@ -70,46 +101,38 @@ TEST_CASE("extract test functions for numbers with invalid inputs") {
     CHECK_INVALID_CONVERSION("", int);
 }
 
-#define CHECK_OUT_OF_RANGE_CONVERSION(type)                                    \
+TEST_CASE_TEMPLATE(
-    {                                                                          \
+    "extract test functions for numbers with out of range inputs", T, short, us,
-        std::string s = std::to_string(std::numeric_limits<type>::max());      \
+    int, ui, long, ul, ll, ull, ss::uint8) {
-        auto t = ss::to_num<type>(s.c_str(), s.c_str() + s.size());            \
+    {
-        CHECK(t.has_value());                                                  \
+        std::string s = std::to_string(numeric_limits<T>::max());
-        for (auto& i : s) {                                                    \
+        auto t = ss::to_num<T>(s.c_str(), s.c_str() + s.size());
-            if (i != '9' && i != '.') {                                        \
+        CHECK(t.has_value());
-                i = '9';                                                       \
+        for (auto& i : s) {
-                break;                                                         \
+            if (i != '9' && i != '.') {
-            }                                                                  \
+                i = '9';
-        }                                                                      \
+                break;
-        t = ss::to_num<type>(s.c_str(), s.c_str() + s.size());                 \
+            }
-        CHECK_FALSE(t.has_value());                                            \
+        }
-    }                                                                          \
+        t = ss::to_num<T>(s.c_str(), s.c_str() + s.size());
-    {                                                                          \
+        CHECK_FALSE(t.has_value());
-        std::string s = std::to_string(std::numeric_limits<type>::min());      \
+    }
-        auto t = ss::to_num<type>(s.c_str(), s.c_str() + s.size());            \
+    {
-        CHECK(t.has_value());                                                  \
+        std::string s = std::to_string(numeric_limits<T>::min());
-        for (auto& i : s) {                                                    \
+        auto t = ss::to_num<T>(s.c_str(), s.c_str() + s.size());
-            if (std::is_signed_v<type> && i != '9' && i != '.') {              \
+        CHECK(t.has_value());
-                i = '9';                                                       \
+        for (auto& i : s) {
-                break;                                                         \
+            if (is_signed<T>::value && i != '9' && i != '.') {
-            } else if (std::is_unsigned_v<type>) {                             \
+                i = '9';
-                s = "-1";                                                      \
+                break;
-                break;                                                         \
+            } else if (is_unsigned<T>::value) {
-            }                                                                  \
+                s = "-1";
-        }                                                                      \
+                break;
-        t = ss::to_num<type>(s.c_str(), s.c_str() + s.size());                 \
+            }
-        CHECK_FALSE(t.has_value());                                            \
+        }
+        t = ss::to_num<T>(s.c_str(), s.c_str() + s.size());
+        CHECK_FALSE(t.has_value());
     }
-
-TEST_CASE("extract test functions for numbers with out of range inputs") {
-    CHECK_OUT_OF_RANGE_CONVERSION(short);
-    CHECK_OUT_OF_RANGE_CONVERSION(us);
-    CHECK_OUT_OF_RANGE_CONVERSION(int);
-    CHECK_OUT_OF_RANGE_CONVERSION(ui);
-    CHECK_OUT_OF_RANGE_CONVERSION(long);
-    CHECK_OUT_OF_RANGE_CONVERSION(ul);
-    CHECK_OUT_OF_RANGE_CONVERSION(ll);
-    CHECK_OUT_OF_RANGE_CONVERSION(ull);
 }
 
 TEST_CASE("extract test functions for boolean values") {
@@ -142,12 +165,12 @@ TEST_CASE("extract test functions for char values") {
     }
 }
 
-TEST_CASE("extract test functions for std::optional") {
+TEST_CASE_TEMPLATE("extract test functions for std::optional", T, int,
-    for (const auto& [i, s] :
+                   ss::int8) {
-         {std::pair<std::optional<int>, std::string>{1, "1"},
+    for (const auto& [i, s] : {std::pair<std::optional<T>, std::string>{1, "1"},
                                {69, "69"},
                                {-4, "-4"}}) {
-        std::optional<int> v;
+        std::optional<T> v;
         REQUIRE(ss::extract(s.c_str(), s.c_str() + s.size(), v));
         REQUIRE(v.has_value());
         CHECK_EQ(*v, i);
@@ -164,7 +187,7 @@ TEST_CASE("extract test functions for std::optional") {
     }
 
     for (const std::string s : {"aa", "xxx", ""}) {
-        std::optional<int> v;
+        std::optional<T> v;
         REQUIRE(ss::extract(s.c_str(), s.c_str() + s.size(), v));
         CHECK_FALSE(v.has_value());
     }
@@ -176,56 +199,57 @@ TEST_CASE("extract test functions for std::optional") {
     }
 }
 
-TEST_CASE("extract test functions for std::variant") {
+TEST_CASE_TEMPLATE("extract test functions for std::variant", T, int,
+                   ss::uint8) {
     {
         std::string s = "22";
         {
-            std::variant<int, double, std::string> var;
+            std::variant<T, double, std::string> var;
             REQUIRE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
             CHECK_NOT_VARIANT(var, double);
             CHECK_NOT_VARIANT(var, std::string);
-            REQUIRE_VARIANT(var, 22, int);
+            REQUIRE_VARIANT(var, 22, T);
         }
         {
-            std::variant<double, int, std::string> var;
+            std::variant<double, T, std::string> var;
             REQUIRE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
-            CHECK_NOT_VARIANT(var, int);
+            CHECK_NOT_VARIANT(var, T);
             CHECK_NOT_VARIANT(var, std::string);
             REQUIRE_VARIANT(var, 22, double);
         }
         {
-            std::variant<std::string, double, int> var;
+            std::variant<std::string, double, T> var;
             REQUIRE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
-            CHECK_NOT_VARIANT(var, int);
+            CHECK_NOT_VARIANT(var, T);
             CHECK_NOT_VARIANT(var, double);
             REQUIRE_VARIANT(var, "22", std::string);
         }
         {
-            std::variant<int> var;
+            std::variant<T> var;
             REQUIRE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
-            REQUIRE_VARIANT(var, 22, int);
+            REQUIRE_VARIANT(var, 22, T);
         }
     }
     {
         std::string s = "22.2";
         {
-            std::variant<int, double, std::string> var;
+            std::variant<T, double, std::string> var;
             REQUIRE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
-            CHECK_NOT_VARIANT(var, int);
+            CHECK_NOT_VARIANT(var, T);
             CHECK_NOT_VARIANT(var, std::string);
             REQUIRE_VARIANT(var, 22.2, double);
         }
         {
-            std::variant<double, int, std::string> var;
+            std::variant<double, T, std::string> var;
             REQUIRE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
-            CHECK_NOT_VARIANT(var, int);
+            CHECK_NOT_VARIANT(var, T);
             CHECK_NOT_VARIANT(var, std::string);
             REQUIRE_VARIANT(var, 22.2, double);
         }
         {
-            std::variant<std::string, double, int> var;
+            std::variant<std::string, double, T> var;
             REQUIRE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
-            CHECK_NOT_VARIANT(var, int);
+            CHECK_NOT_VARIANT(var, T);
             CHECK_NOT_VARIANT(var, double);
             REQUIRE_VARIANT(var, "22.2", std::string);
         }
@@ -233,45 +257,45 @@ TEST_CASE("extract test functions for std::variant") {
     {
         std::string s = "2.2.2";
         {
-            std::variant<int, double, std::string> var;
+            std::variant<T, double, std::string> var;
             REQUIRE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
-            CHECK_NOT_VARIANT(var, int);
+            CHECK_NOT_VARIANT(var, T);
             CHECK_NOT_VARIANT(var, double);
             REQUIRE_VARIANT(var, "2.2.2", std::string);
         }
         {
-            std::variant<double, std::string, int> var;
+            std::variant<double, std::string, T> var;
             REQUIRE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
-            CHECK_NOT_VARIANT(var, int);
+            CHECK_NOT_VARIANT(var, T);
             CHECK_NOT_VARIANT(var, double);
             REQUIRE_VARIANT(var, "2.2.2", std::string);
         }
         {
-            std::variant<std::string, double, int> var;
+            std::variant<std::string, double, T> var;
             REQUIRE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
-            CHECK_NOT_VARIANT(var, int);
+            CHECK_NOT_VARIANT(var, T);
             CHECK_NOT_VARIANT(var, double);
             REQUIRE_VARIANT(var, "2.2.2", std::string);
         }
         {
-            std::variant<int, double> var;
+            std::variant<T, double> var;
             REQUIRE_FALSE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
 
-            REQUIRE_VARIANT(var, int{}, int);
+            REQUIRE_VARIANT(var, T{}, T);
             CHECK_NOT_VARIANT(var, double);
         }
         {
-            std::variant<double, int> var;
+            std::variant<double, T> var;
             REQUIRE_FALSE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
 
             REQUIRE_VARIANT(var, double{}, double);
-            CHECK_NOT_VARIANT(var, int);
+            CHECK_NOT_VARIANT(var, T);
         }
         {
-            std::variant<int> var;
+            std::variant<T> var;
             REQUIRE_FALSE(ss::extract(s.c_str(), s.c_str() + s.size(), var));
 
-            REQUIRE_VARIANT(var, int{}, int);
+            REQUIRE_VARIANT(var, T{}, T);
         }
     }
 }

test/test_helpers.hpp

@@ -1,7 +1,11 @@
 #pragma once
+#include <algorithm>
 #include <ctime>
 #include <filesystem>
+#include <fstream>
 #include <iomanip>
+#include <ss/common.hpp>
+#include <ss/setup.hpp>
 #include <sstream>
 #include <string>
 #include <vector>
@@ -12,7 +16,30 @@
 #include <doctest.h>
 #endif
 
+namespace ss {
+template <typename... Ts>
+class parser;
+} /* ss */
+
 namespace {
+
+struct bool_error {};
+
+template <typename T, typename U = bool_error>
+struct config {
+    using BufferMode = T;
+    using ErrorMode = U;
+
+    constexpr static auto ThrowOnError = std::is_same_v<U, ss::throw_on_error>;
+    constexpr static auto StringError = std::is_same_v<U, ss::string_error>;
+};
+
+#define ParserOptionCombinations                                               \
+    config<std::true_type>, config<std::true_type, ss::string_error>,          \
+        config<std::true_type, ss::throw_on_error>, config<std::false_type>,   \
+        config<std::false_type, ss::string_error>,                             \
+        config<std::false_type, ss::throw_on_error>
+
 struct buffer {
     std::string data_;
 
@@ -34,27 +61,34 @@ struct buffer {
 
 [[maybe_unused]] inline buffer buff;
 
-std::string time_now_rand() {
+[[maybe_unused]] std::string time_now_rand() {
+    std::srand(std::time(nullptr));
     std::stringstream ss;
     auto t = std::time(nullptr);
     auto tm = *std::localtime(&t);
     ss << std::put_time(&tm, "%d%m%Y%H%M%S");
-    srand(time(nullptr));
+    std::srand(std::time(nullptr));
     return ss.str() + std::to_string(rand());
 }
 
 struct unique_file_name {
     static inline int i = 0;
 
-    const std::string name;
+    std::string name;
 
-    unique_file_name(const std::string& test)
+    unique_file_name(const std::string& test) {
-        : name{"random_" + test + "_" + std::to_string(i++) + "_" +
+        do {
-               time_now_rand() + "_file.csv"} {
+            name = "ssp_test_" + test + "_" + std::to_string(i++) + "_" +
+                   time_now_rand() + "_file.csv";
+        } while (std::filesystem::exists(name));
     }
 
     ~unique_file_name() {
+        try {
             std::filesystem::remove(name);
+        } catch (const std::filesystem::filesystem_error& e) {
+            std::cerr << e.what() << std::endl;
+        }
     }
 };
 
@@ -112,8 +146,8 @@ struct unique_file_name {
     }
 
 template <typename T>
-std::vector<std::vector<T>> vector_combinations(const std::vector<T>& v,
+[[maybe_unused]] std::vector<std::vector<T>> vector_combinations(
-                                                size_t n) {
+    const std::vector<T>& v, size_t n) {
     std::vector<std::vector<T>> ret;
     if (n <= 1) {
         for (const auto& i : v) {
@@ -126,9 +160,68 @@ std::vector<std::vector<T>> vector_combinations(const std::vector<T>& v,
     for (const auto& i : v) {
         for (auto j : inner_combinations) {
             j.insert(j.begin(), i);
-            ret.push_back(move(j));
+            ret.push_back(std::move(j));
         }
     }
     return ret;
 }
+
+[[maybe_unused]] std::string make_buffer(const std::string& file_name) {
+    std::ifstream in{file_name, std::ios::binary};
+    std::string tmp;
+    std::string out;
+
+    auto copy_if_whitespaces = [&] {
+        std::string matches = "\n\r\t ";
+        while (std::any_of(matches.begin(), matches.end(),
+                           [&](auto c) { return in.peek() == c; })) {
+            if (in.peek() == '\r') {
+                out += "\r\n";
+                in.ignore(2);
+            } else {
+                out += std::string{static_cast<char>(in.peek())};
+                in.ignore(1);
+            }
+        }
+    };
+
+    out.reserve(sizeof(out) + 1);
+
+    copy_if_whitespaces();
+    while (in >> tmp) {
+        out += tmp;
+        copy_if_whitespaces();
+    }
+    return out;
+}
+
+template <bool buffer_mode, typename... Ts>
+std::tuple<ss::parser<Ts...>, std::string> make_parser_impl(
+    const std::string& file_name, std::string delim = ss::default_delimiter) {
+    if (buffer_mode) {
+        auto buffer = make_buffer(file_name);
+        return {ss::parser<Ts...>{buffer.data(), buffer.size(), delim},
+                std::move(buffer)};
+    } else {
+        return {ss::parser<Ts...>{file_name, delim}, std::string{}};
+    }
+}
+
+template <bool buffer_mode, typename ErrorMode, typename... Ts>
+[[maybe_unused]] std::enable_if_t<
+    !std::is_same_v<ErrorMode, bool_error>,
+    std::tuple<ss::parser<ErrorMode, Ts...>, std::string>>
+make_parser(const std::string& file_name,
+            std::string delim = ss::default_delimiter) {
+    return make_parser_impl<buffer_mode, ErrorMode, Ts...>(file_name, delim);
+}
+
+template <bool buffer_mode, typename ErrorMode, typename... Ts>
+[[maybe_unused]] std::enable_if_t<std::is_same_v<ErrorMode, bool_error>,
+                                  std::tuple<ss::parser<Ts...>, std::string>>
+make_parser(const std::string& file_name,
+            std::string delim = ss::default_delimiter) {
+    return make_parser_impl<buffer_mode, Ts...>(file_name, delim);
+}
+
 } /* namespace */

test/test_parser1.hpp

@@ -0,0 +1,112 @@
+#pragma once
+
+#include "test_helpers.hpp"
+#include <algorithm>
+#include <filesystem>
+#include <fstream>
+#include <iomanip>
+#include <iostream>
+#include <ss/parser.hpp>
+#include <sstream>
+#include <unordered_map>
+#include <unordered_set>
+
+namespace {
+[[maybe_unused]] void replace_all(std::string& s, const std::string& from,
+                                  const std::string& to) {
+    if (from.empty()) return;
+    size_t start_pos = 0;
+    while ((start_pos = s.find(from, start_pos)) != std::string::npos) {
+        s.replace(start_pos, from.length(), to);
+        start_pos += to.length();
+    }
+}
+
+template <typename... Ts>
+void expect_error_on_command(ss::parser<Ts...>& p,
+                             const std::function<void()> command) {
+    if (ss::setup<Ts...>::throw_on_error) {
+        try {
+            command();
+        } catch (const std::exception& e) {
+            CHECK_FALSE(std::string{e.what()}.empty());
+        }
+    } else {
+        command();
+        CHECK(!p.valid());
+        if constexpr (ss::setup<Ts...>::string_error) {
+            CHECK_FALSE(p.error_msg().empty());
+        }
+    }
+}
+
+[[maybe_unused]] void update_if_crlf(std::string& s) {
+#ifdef _WIN32
+    replace_all(s, "\r\n", "\n");
+#else
+    (void)(s);
+#endif
+}
+
+struct X {
+    constexpr static auto delim = ",";
+    constexpr static auto empty = "_EMPTY_";
+    int i;
+    double d;
+    std::string s;
+
+    std::string to_string() const {
+        if (s == empty) {
+            return "";
+        }
+
+        return std::to_string(i)
+            .append(delim)
+            .append(std::to_string(d))
+            .append(delim)
+            .append(s);
+    }
+    auto tied() const {
+        return std::tie(i, d, s);
+    }
+};
+
+template <typename T>
+std::enable_if_t<ss::has_m_tied_t<T>, bool> operator==(const T& lhs,
+                                                       const T& rhs) {
+    return lhs.tied() == rhs.tied();
+}
+
+template <typename T>
+static void make_and_write(const std::string& file_name,
+                           const std::vector<T>& data,
+                           const std::vector<std::string>& header = {},
+                           bool new_line_eof = true) {
+    std::ofstream out{file_name};
+
+#ifdef _WIN32
+    std::vector<const char*> new_lines = {"\n"};
+#else
+    std::vector<const char*> new_lines = {"\n", "\r\n"};
+#endif
+
+    for (const auto& i : header) {
+        if (&i != &header.front()) {
+            out << T::delim;
+        }
+        out << i;
+    }
+
+    if (!header.empty()) {
+        out << new_lines.front();
+    }
+
+    for (size_t i = 0; i < data.size(); ++i) {
+        out << data[i].to_string();
+        if (new_line_eof || i + 1 < data.size()) {
+            out << new_lines[i % new_lines.size()];
+        }
+    }
+}
+
+} /* namespace */

test/test_parser1_1.cpp

@@ -0,0 +1,674 @@
+#include "test_parser1.hpp"
+
+TEST_CASE("test file not found") {
+    unique_file_name f{"file_not_found"};
+
+    {
+        ss::parser p{f.name, ","};
+        CHECK_FALSE(p.valid());
+    }
+
+    {
+        ss::parser<ss::string_error> p{f.name, ","};
+        CHECK_FALSE(p.valid());
+        CHECK_FALSE(p.error_msg().empty());
+    }
+
+    try {
+        ss::parser<ss::throw_on_error> p{f.name, ","};
+        FAIL("Expected exception...");
+    } catch (const std::exception& e) {
+        CHECK_FALSE(std::string{e.what()}.empty());
+    }
+}
+
+TEST_CASE("test null buffer") {
+    {
+        ss::parser p{nullptr, 10, ","};
+        CHECK_FALSE(p.valid());
+    }
+
+    {
+        ss::parser<ss::string_error> p{nullptr, 10, ","};
+        CHECK_FALSE(p.valid());
+        CHECK_FALSE(p.error_msg().empty());
+    }
+
+    try {
+        ss::parser<ss::throw_on_error> p{nullptr, 10, ","};
+        FAIL("Expected exception...");
+    } catch (const std::exception& e) {
+        CHECK_FALSE(std::string{e.what()}.empty());
+    }
+}
+
+struct Y {
+    constexpr static auto delim = ",";
+    std::string s1;
+    std::string s2;
+    std::string s3;
+
+    std::string to_string() const {
+        return std::string{}
+            .append(s1)
+            .append(delim)
+            .append(s2)
+            .append(delim)
+            .append(s3);
+    }
+
+    auto tied() const {
+        return std::tie(s1, s2, s3);
+    }
+};
+
+TEST_CASE_TEMPLATE("test position method", T, ParserOptionCombinations) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+
+    unique_file_name f{"position_method"};
+    std::vector<Y> data = {{"1", "21", "x"},   {"321", "4", "y"},
+                           {"54", "6", "zz"},  {"7", "876", "uuuu"},
+                           {"910", "10", "v"}, {"10", "321", "ww"}};
+    make_and_write(f.name, data);
+
+    auto [p, buff] = make_parser<buffer_mode, ErrorMode>(f.name);
+    auto data_at = [&buff = buff, &f = f](auto n) {
+        if (!buff.empty()) {
+            return buff[n];
+        } else {
+            auto file = std::fopen(f.name.c_str(), "r");
+            std::fseek(file, n, SEEK_SET);
+            return static_cast<char>(std::fgetc(file));
+        }
+    };
+
+    while (!p.eof()) {
+        auto curr_char = p.position();
+        const auto& [s1, s2, s3] =
+            p.template get_next<std::string, std::string, std::string>();
+
+        auto s = s1 + "," + s2 + "," + s3;
+
+        for (size_t i = 0; i < s1.size(); ++i) {
+            CHECK_EQ(data_at(curr_char + i), s[i]);
+        }
+
+        auto last_char = data_at(curr_char + s.size());
+        CHECK((last_char == '\n' || last_char == '\r'));
+    }
+}
+
+TEST_CASE_TEMPLATE("test line method", T, ParserOptionCombinations) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+
+    unique_file_name f{"line_method"};
+    std::vector<Y> data = {{"1", "21", "x"},   {"321", "4", "y"},
+                           {"54", "6", "zz"},  {"7", "876", "uuuu"},
+                           {"910", "10", "v"}, {"10", "321", "ww"}};
+    make_and_write(f.name, data);
+
+    auto [p, buff] = make_parser<buffer_mode, ErrorMode>(f.name);
+
+    auto expected_line = 0;
+    CHECK_EQ(p.line(), expected_line);
+
+    while (!p.eof()) {
+        auto _ = p.template get_next<std::string, std::string, std::string>();
+        ++expected_line;
+        CHECK_EQ(p.line(), expected_line);
+    }
+
+    CHECK_EQ(p.line(), data.size());
+}
+
+TEST_CASE_TEMPLATE("parser test various valid cases", T,
+                   ParserOptionCombinations) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+
+    unique_file_name f{"various_valid_cases"};
+    std::vector<X> data = {{1, 2, "x"}, {3, 4, "y"},  {5, 6, "z"},
+                           {7, 8, "u"}, {9, 10, "v"}, {11, 12, "w"}};
+    make_and_write(f.name, data);
+    auto csv_data_buffer = make_buffer(f.name);
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        ss::parser p0{std::move(p)};
+        p = std::move(p0);
+        std::vector<X> i;
+
+        auto [p2, __] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i2;
+
+        auto move_rotate = [&p = p, &p0 = p0] {
+            auto p1 = std::move(p);
+            p0 = std::move(p1);
+            p = std::move(p0);
+        };
+
+        while (!p.eof()) {
+            move_rotate();
+            auto a = p.template get_next<int, double, std::string>();
+            i.emplace_back(ss::to_object<X>(a));
+        }
+
+        for (const auto& a : p2.template iterate<int, double, std::string>()) {
+            i2.emplace_back(ss::to_object<X>(a));
+        }
+
+        CHECK_EQ(i, data);
+        CHECK_EQ(i2, data);
+    }
+
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i;
+
+        auto [p2, __] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i2;
+
+        auto [p3, ___] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i3;
+
+        std::vector<X> expected = {std::begin(data) + 1, std::end(data)};
+        using tup = std::tuple<int, double, std::string>;
+
+        p.ignore_next();
+        while (!p.eof()) {
+            auto a = p.template get_next<tup>();
+            i.emplace_back(ss::to_object<X>(a));
+        }
+
+        p2.ignore_next();
+        for (const auto& a : p2.template iterate<tup>()) {
+            i2.emplace_back(ss::to_object<X>(a));
+        }
+
+        p3.ignore_next();
+        for (auto it = p3.template iterate<tup>().begin();
+             it != p3.template iterate<tup>().end(); ++it) {
+            i3.emplace_back(ss::to_object<X>(*it));
+        }
+
+        CHECK_EQ(i, expected);
+        CHECK_EQ(i2, expected);
+        CHECK_EQ(i3, expected);
+    }
+
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i;
+        auto [p2, __] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i2;
+
+        while (!p.eof()) {
+            i.push_back(p.template get_object<X, int, double, std::string>());
+        }
+
+        for (auto&& a :
+             p2.template iterate_object<X, int, double, std::string>()) {
+            i2.push_back(std::move(a));
+        }
+
+        CHECK_EQ(i, data);
+        CHECK_EQ(i2, data);
+    }
+
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i;
+
+        for (auto&& a :
+             p.template iterate_object<X, int, double, std::string>()) {
+            i.push_back(std::move(a));
+        }
+
+        CHECK_EQ(i, data);
+    }
+
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i;
+
+        auto [p2, __] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i2;
+
+        using tup = std::tuple<int, double, std::string>;
+        while (!p.eof()) {
+            i.push_back(p.template get_object<X, tup>());
+        }
+
+        for (auto it = p2.template iterate_object<X, tup>().begin();
+             it != p2.template iterate_object<X, tup>().end(); it++) {
+            i2.push_back({it->i, it->d, it->s});
+        }
+
+        CHECK_EQ(i, data);
+        CHECK_EQ(i2, data);
+    }
+
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i;
+
+        using tup = std::tuple<int, double, std::string>;
+        for (auto&& a : p.template iterate_object<X, tup>()) {
+            i.push_back(std::move(a));
+        }
+
+        CHECK_EQ(i, data);
+    }
+
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i;
+
+        while (!p.eof()) {
+            i.push_back(p.template get_next<X>());
+        }
+
+        CHECK_EQ(i, data);
+    }
+
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i;
+
+        for (auto&& a : p.template iterate<X>()) {
+            i.push_back(std::move(a));
+        }
+
+        CHECK_EQ(i, data);
+    }
+
+    {
+        constexpr int excluded = 3;
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i;
+
+        auto [p2, __] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i2;
+
+        while (!p.eof()) {
+            try {
+                auto a = p.template get_object<X, ss::ax<int, excluded>, double,
+                                               std::string>();
+                if (p.valid()) {
+                    i.push_back(a);
+                }
+            } catch (...) {
+                // ignore
+            };
+        }
+
+        if (!T::ThrowOnError) {
+            for (auto&& a : p2.template iterate_object<X, ss::ax<int, excluded>,
+                                                       double, std::string>()) {
+                if (p2.valid()) {
+                    i2.push_back(std::move(a));
+                }
+            }
+        }
+
+        std::vector<X> expected;
+        for (auto& x : data) {
+            if (x.i != excluded) {
+                expected.push_back(x);
+            }
+        }
+
+        std::copy_if(data.begin(), data.end(), expected.begin(),
+                     [&](const X& x) { return x.i != excluded; });
+        CHECK_EQ(i, expected);
+
+        if (!T::ThrowOnError) {
+            CHECK_EQ(i2, expected);
+        }
+    }
+
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i;
+
+        auto [p2, __] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i2;
+
+        while (!p.eof()) {
+            try {
+                auto a = p.template get_object<X, ss::nx<int, 3>, double,
+                                               std::string>();
+                if (p.valid()) {
+                    i.push_back(a);
+                }
+            } catch (...) {
+                // ignore
+            }
+        }
+
+        if (!T::ThrowOnError) {
+            for (auto&& a : p2.template iterate_object<X, ss::nx<int, 3>,
+                                                       double, std::string>()) {
+                if (p2.valid()) {
+                    i2.push_back(std::move(a));
+                }
+            }
+        }
+
+        std::vector<X> expected = {{3, 4, "y"}};
+        CHECK_EQ(i, expected);
+        if (!T::ThrowOnError) {
+            CHECK_EQ(i2, expected);
+        }
+    }
+
+    {
+        unique_file_name empty_f{"various_valid_cases"};
+        std::vector<X> empty_data = {};
+
+        make_and_write(empty_f.name, empty_data);
+
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(empty_f.name, ",");
+        std::vector<X> i;
+
+        auto [p2, __] = make_parser<buffer_mode, ErrorMode>(empty_f.name, ",");
+        std::vector<X> i2;
+
+        while (!p.eof()) {
+            i.push_back(p.template get_next<X>());
+        }
+
+        for (auto&& a : p2.template iterate<X>()) {
+            i2.push_back(std::move(a));
+        }
+
+        CHECK(i.empty());
+        CHECK(i2.empty());
+    }
+}
+
+using test_tuple = std::tuple<double, char, double>;
+struct test_struct {
+    int i;
+    double d;
+    char c;
+    auto tied() {
+        return std::tie(i, d, c);
+    }
+};
+
+static inline void expect_test_struct(const test_struct&) {
+}
+
+TEST_CASE_TEMPLATE("parser test composite conversion", BufferMode,
+                   std::true_type, std::false_type) {
+    constexpr auto buffer_mode = BufferMode::value;
+    unique_file_name f{"composite_conversion"};
+    {
+        std::ofstream out{f.name};
+        for (auto& i :
+             {"10,a,11.1", "10,20,11.1", "junk", "10,11.1", "1,11.1,a", "junk",
+              "10,junk", "11,junk", "10,11.1,c", "10,20", "10,22.2,f"}) {
+            out << i << std::endl;
+        }
+    }
+
+    auto [p, _] = make_parser<buffer_mode, ss::string_error>(f.name, ",");
+    auto fail = [] { FAIL(""); };
+    auto expect_error = [](auto error) { CHECK(!error.empty()); };
+    auto ignore_error = [] {};
+
+    REQUIRE(p.valid());
+    REQUIRE_FALSE(p.eof());
+
+    {
+        constexpr static auto expectedData = std::tuple{10, 'a', 11.1};
+
+        auto [d1, d2, d3, d4] =
+            p.template try_next<int, int, double>(fail)
+                .template or_else<test_struct>(fail)
+                .template or_else<int, char, double>(
+                    [&](auto&& data) { CHECK_EQ(data, expectedData); })
+                .on_error(fail)
+                .template or_else<test_tuple>(fail)
+                .values();
+
+        REQUIRE(p.valid());
+        REQUIRE_FALSE(d1);
+        REQUIRE_FALSE(d2);
+        REQUIRE(d3);
+        REQUIRE_FALSE(d4);
+        CHECK_EQ(*d3, expectedData);
+    }
+
+    {
+        REQUIRE(!p.eof());
+        constexpr static auto expectedData = std::tuple{10, 20, 11.1};
+
+        auto [d1, d2, d3, d4] =
+            p.template try_next<int, int, double>(
+                 [&](auto& i1, auto i2, double d) {
+                     CHECK_EQ(std::tie(i1, i2, d), expectedData);
+                 })
+                .on_error(fail)
+                .template or_object<test_struct, int, double, char>(fail)
+                .on_error(fail)
+                .template or_else<test_tuple>(fail)
+                .on_error(fail)
+                .template or_else<int, char, double>(fail)
+                .values();
+
+        REQUIRE(p.valid());
+        REQUIRE(d1);
+        REQUIRE_FALSE(d2);
+        REQUIRE_FALSE(d3);
+        REQUIRE_FALSE(d4);
+        CHECK_EQ(*d1, expectedData);
+    }
+
+    {
+        REQUIRE(!p.eof());
+
+        auto [d1, d2, d3, d4, d5] =
+            p.template try_object<test_struct, int, double, char>(fail)
+                .on_error(expect_error)
+                .template or_else<int, char, char>(fail)
+                .template or_else<test_struct>(fail)
+                .template or_else<test_tuple>(fail)
+                .template or_else<int, char, double>(fail)
+                .values();
+
+        REQUIRE_FALSE(p.valid());
+        REQUIRE_FALSE(d1);
+        REQUIRE_FALSE(d2);
+        REQUIRE_FALSE(d3);
+        REQUIRE_FALSE(d4);
+        REQUIRE_FALSE(d5);
+    }
+
+    {
+        REQUIRE(!p.eof());
+
+        auto [d1, d2] =
+            p.template try_next<int, double>([](auto& i, auto& d) {
+                 REQUIRE_EQ(std::tie(i, d), std::tuple{10, 11.1});
+             })
+                .template or_else<int, double>([](auto&, auto&) { FAIL(""); })
+                .values();
+
+        REQUIRE(p.valid());
+        REQUIRE(d1);
+        REQUIRE_FALSE(d2);
+    }
+
+    {
+        REQUIRE(!p.eof());
+
+        auto [d1, d2] =
+            p.template try_next<int, double>([](auto&, auto&) { FAIL(""); })
+                .template or_else<test_struct>(expect_test_struct)
+                .values();
+
+        REQUIRE(p.valid());
+        REQUIRE_FALSE(d1);
+        REQUIRE(d2);
+        CHECK_EQ(d2->tied(), std::tuple{1, 11.1, 'a'});
+    }
+
+    {
+        REQUIRE(!p.eof());
+
+        auto [d1, d2, d3, d4, d5] =
+            p.template try_next<int, int, double>(fail)
+                .template or_object<test_struct, int, double, char>()
+                .template or_else<test_struct>(expect_test_struct)
+                .template or_else<test_tuple>(fail)
+                .template or_else<std::tuple<int, double>>(fail)
+                .on_error(ignore_error)
+                .on_error(expect_error)
+                .values();
+
+        REQUIRE_FALSE(p.valid());
+        REQUIRE_FALSE(d1);
+        REQUIRE_FALSE(d2);
+        REQUIRE_FALSE(d3);
+        REQUIRE_FALSE(d4);
+        REQUIRE_FALSE(d5);
+    }
+
+    {
+        REQUIRE(!p.eof());
+
+        auto [d1, d2] =
+            p.template try_next<int, std::optional<int>>()
+                .on_error(ignore_error)
+                .on_error(fail)
+                .template or_else<std::tuple<int, std::string>>(fail)
+                .on_error(ignore_error)
+                .on_error(fail)
+                .on_error(ignore_error)
+                .values();
+
+        REQUIRE(p.valid());
+        REQUIRE(d1);
+        REQUIRE_FALSE(d2);
+        CHECK_EQ(*d1, std::tuple{10, std::nullopt});
+    }
+
+    {
+        REQUIRE_FALSE(p.eof());
+
+        auto [d1, d2] =
+            p.template try_next<int, std::variant<int, std::string>>()
+                .on_error(fail)
+                .template or_else<std::tuple<int, std::string>>(fail)
+                .on_error(fail)
+                .values();
+
+        REQUIRE(p.valid());
+        REQUIRE(d1);
+        REQUIRE_FALSE(d2);
+        CHECK_EQ(*d1, std::tuple{11, std::variant<int, std::string>{"junk"}});
+    }
+
+    {
+        REQUIRE(!p.eof());
+
+        auto [d1, d2] = p.template try_object<test_struct, int, double, char>()
+                            .template or_else<int>(fail)
+                            .values();
+        REQUIRE(p.valid());
+        REQUIRE(d1);
+        REQUIRE_FALSE(d2);
+        CHECK_EQ(d1->tied(), std::tuple{10, 11.1, 'c'});
+    }
+
+    {
+        REQUIRE_FALSE(p.eof());
+
+        auto [d1, d2, d3, d4] =
+            p.template try_next<int, int>([] { return false; })
+                .template or_else<int, double>([](auto&) { return false; })
+                .template or_else<int, int>()
+                .template or_else<int, int>(fail)
+                .values();
+
+        REQUIRE(p.valid());
+        REQUIRE_FALSE(d1);
+        REQUIRE_FALSE(d2);
+        REQUIRE(d3);
+        REQUIRE_FALSE(d4);
+        CHECK_EQ(d3.value(), std::tuple{10, 20});
+    }
+
+    {
+        REQUIRE(!p.eof());
+
+        auto [d1, d2, d3, d4] =
+            p.template try_object<test_struct, int, double, char>(
+                 [] { return false; })
+                .template or_else<int, double>([](auto&) { return false; })
+                .template or_object<test_struct, int, double, char>()
+                .template or_else<int, int>(fail)
+                .values();
+
+        REQUIRE(p.valid());
+        REQUIRE_FALSE(d1);
+        REQUIRE_FALSE(d2);
+        REQUIRE(d3);
+        REQUIRE_FALSE(d4);
+        CHECK_EQ(d3->tied(), std::tuple{10, 22.2, 'f'});
+    }
+
+    CHECK(p.eof());
+}
+
+template <bool buffer_mode, typename... Ts>
+void test_no_new_line_at_eof_impl(const std::vector<X>& data) {
+    unique_file_name f{"no_new_line_at_eof"};
+    make_and_write(f.name, data, {}, false);
+
+    auto [p, _] = make_parser<buffer_mode, Ts...>(f.name);
+    std::vector<X> parsed_data;
+
+    for (const auto& el : p.template iterate<X>()) {
+        parsed_data.push_back(el);
+    }
+
+    CHECK_EQ(data, parsed_data);
+}
+
+template <bool buffer_mode, typename... Ts>
+void test_no_new_line_at_eof() {
+    test_no_new_line_at_eof_impl<buffer_mode, Ts...>({});
+    test_no_new_line_at_eof_impl<buffer_mode, Ts...>({{1, 2, "X"}});
+    test_no_new_line_at_eof_impl<buffer_mode, Ts...>({{1, 2, "X"}, {}});
+    test_no_new_line_at_eof_impl<buffer_mode, Ts...>(
+        {{1, 2, "X"}, {3, 4, "YY"}});
+    test_no_new_line_at_eof_impl<buffer_mode, Ts...>(
+        {{1, 2, "X"}, {3, 4, "YY"}, {}});
+    test_no_new_line_at_eof_impl<buffer_mode, Ts...>(
+        {{1, 2, "X"}, {3, 4, "YY"}, {5, 6, "ZZZ"}, {7, 8, "UUU"}});
+
+    for (size_t i = 0; i < 2 * ss::get_line_initial_buffer_size; ++i) {
+        test_no_new_line_at_eof_impl<buffer_mode, Ts...>(
+            {{1, 2, std::string(i, 'X')}});
+
+        for (size_t j = 0; j < 2 * ss::get_line_initial_buffer_size; j += 13) {
+
+            test_no_new_line_at_eof_impl<buffer_mode, Ts...>(
+                {{1, 2, std::string(i, 'X')}, {3, 4, std::string(j, 'Y')}});
+
+            test_no_new_line_at_eof_impl<buffer_mode, Ts...>(
+                {{1, 2, std::string(j, 'X')}, {3, 4, std::string(i, 'Y')}});
+        }
+    }
+}
+
+TEST_CASE_TEMPLATE("test no new line at end of data", T,
+                   ParserOptionCombinations) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+    test_no_new_line_at_eof<buffer_mode, ErrorMode>();
+}

test/test_parser1_2.cpp

@@ -0,0 +1,262 @@
+#include "test_parser1.hpp"
+
+struct my_string {
+    char* data{nullptr};
+
+    my_string() = default;
+
+    ~my_string() {
+        delete[] data;
+    }
+
+    // make sure no object is copied
+    my_string(const my_string&) = delete;
+    my_string& operator=(const my_string&) = delete;
+
+    my_string(my_string&& other) : data{other.data} {
+        other.data = nullptr;
+    }
+
+    my_string& operator=(my_string&& other) {
+        data = other.data;
+        return *this;
+    }
+};
+
+template <>
+inline bool ss::extract(const char* begin, const char* end, my_string& s) {
+    size_t size = end - begin;
+    s.data = new char[size + 1];
+    strncpy(s.data, begin, size);
+    s.data[size] = '\0';
+    return true;
+}
+
+struct xyz {
+    my_string x;
+    my_string y;
+    my_string z;
+    auto tied() {
+        return std::tie(x, y, z);
+    }
+};
+
+TEST_CASE_TEMPLATE("test moving of parsed composite values", T,
+                   config<std::true_type>, config<std::false_type>,
+                   config<std::true_type, ss::string_error>,
+                   config<std::false_type, ss::string_error>) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+
+    // to compile is enough
+    return;
+    auto [p, _] = make_parser<buffer_mode, ErrorMode>("", "");
+    p.template try_next<my_string, my_string, my_string>()
+        .template or_else<my_string, my_string, my_string, my_string>(
+            [](auto&&) {})
+        .template or_else<my_string>([](auto&) {})
+        .template or_else<xyz>([](auto&&) {})
+        .template or_object<xyz, my_string, my_string, my_string>([](auto&&) {})
+        .template or_else<std::tuple<my_string, my_string, my_string>>(
+            [](auto&, auto&, auto&) {});
+}
+
+TEST_CASE_TEMPLATE("parser test string error mode", BufferMode, std::true_type,
+                   std::false_type) {
+    unique_file_name f{"string_error"};
+    {
+        std::ofstream out{f.name};
+        out << "junk" << std::endl;
+        out << "junk" << std::endl;
+    }
+
+    auto [p, _] = make_parser<BufferMode::value, ss::string_error>(f.name, ",");
+
+    REQUIRE_FALSE(p.eof());
+    p.template get_next<int>();
+    CHECK_FALSE(p.valid());
+    CHECK_FALSE(p.error_msg().empty());
+}
+
+TEST_CASE_TEMPLATE("parser throw on error mode", BufferMode, std::true_type,
+                   std::false_type) {
+    unique_file_name f{"throw_on_error"};
+    {
+        std::ofstream out{f.name};
+        out << "junk" << std::endl;
+        out << "junk" << std::endl;
+    }
+
+    auto [p, _] =
+        make_parser<BufferMode::value, ss::throw_on_error>(f.name, ",");
+
+    REQUIRE_FALSE(p.eof());
+    try {
+        p.template get_next<int>();
+        FAIL("Expected exception...");
+    } catch (const std::exception& e) {
+        CHECK_FALSE(std::string{e.what()}.empty());
+    }
+}
+
+static inline std::string no_quote(const std::string& s) {
+    if (!s.empty() && s[0] == '"') {
+        return {std::next(begin(s)), std::prev(end(s))};
+    }
+    return s;
+}
+
+TEST_CASE_TEMPLATE("test quote multiline", T, ParserOptionCombinations) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+
+    unique_file_name f{"quote_multiline"};
+    std::vector<X> data = {{1, 2, "\"x\r\nx\nx\""},
+                           {3, 4, "\"y\ny\r\ny\""},
+                           {5, 6, "\"z\nz\""},
+                           {7, 8, "\"u\"\"\""},
+                           {9, 10, "v"},
+                           {11, 12, "\"w\n\""}};
+    for (auto& [_, __, s] : data) {
+        update_if_crlf(s);
+    }
+
+    make_and_write(f.name, data);
+    for (auto& [_, __, s] : data) {
+        s = no_quote(s);
+        if (s[0] == 'u') {
+            s = "u\"";
+        }
+    }
+
+    auto [p, _] = make_parser<buffer_mode, ErrorMode, ss::multiline,
+                              ss::quote<'"'>>(f.name, ",");
+
+    std::vector<X> i;
+
+    while (!p.eof()) {
+        auto a = p.template get_next<int, double, std::string>();
+        i.emplace_back(ss::to_object<X>(a));
+    }
+
+    for (auto& [_, __, s] : i) {
+        update_if_crlf(s);
+    }
+    CHECK_EQ(i, data);
+
+    auto [p_no_multiline, __] =
+        make_parser<buffer_mode, ErrorMode, ss::quote<'"'>>(f.name, ",");
+    while (!p.eof()) {
+        auto command = [&p_no_multiline = p_no_multiline] {
+            p_no_multiline.template get_next<int, double, std::string>();
+        };
+        expect_error_on_command(p_no_multiline, command);
+    }
+}
+
+static inline std::string no_escape(std::string& s) {
+    s.erase(std::remove(begin(s), end(s), '\\'), end(s));
+    return s;
+}
+
+TEST_CASE_TEMPLATE("test escape multiline", T, ParserOptionCombinations) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+
+    unique_file_name f{"escape_multiline"};
+    std::vector<X> data = {{1, 2, "x\\\nx\\\r\nx"},
+                           {5, 6, "z\\\nz\\\nz"},
+                           {7, 8, "u"},
+                           {3, 4, "y\\\ny\\\ny"},
+                           {9, 10, "v\\\\"},
+                           {11, 12, "w\\\n"}};
+    for (auto& [_, __, s] : data) {
+        update_if_crlf(s);
+    }
+
+    make_and_write(f.name, data);
+    for (auto& [_, __, s] : data) {
+        s = no_escape(s);
+        if (s == "v") {
+            s = "v\\";
+        }
+    }
+
+    auto [p, _] = make_parser<buffer_mode, ErrorMode, ss::multiline,
+                              ss::escape<'\\'>>(f.name, ",");
+    std::vector<X> i;
+
+    while (!p.eof()) {
+        auto a = p.template get_next<int, double, std::string>();
+        i.emplace_back(ss::to_object<X>(a));
+    }
+
+    for (auto& [_, __, s] : i) {
+        update_if_crlf(s);
+    }
+    CHECK_EQ(i, data);
+
+    auto [p_no_multiline, __] =
+        make_parser<buffer_mode, ErrorMode, ss::escape<'\\'>>(f.name, ",");
+    while (!p.eof()) {
+        auto command = [&p_no_multiline = p_no_multiline] {
+            auto a =
+                p_no_multiline.template get_next<int, double, std::string>();
+        };
+        expect_error_on_command(p_no_multiline, command);
+    }
+}
+
+TEST_CASE_TEMPLATE("test quote escape multiline", T, ParserOptionCombinations) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+
+    unique_file_name f{"quote_escape_multiline"};
+    {
+        std::ofstream out{f.name};
+        out << "1,2,\"just\\\n\nstrings\"" << std::endl;
+#ifndef _WIN32
+        out << "3,4,\"just\r\nsome\\\r\n\n\\\nstrings\"" << std::endl;
+        out << "5,6,\"just\\\n\\\r\n\r\n\nstrings" << std::endl;
+#else
+        out << "3,4,\"just\nsome\\\n\n\\\nstrings\"" << std::endl;
+        out << "5,6,\"just\\\n\\\n\n\nstrings" << std::endl;
+#endif
+        out << "7,8,\"just strings\"" << std::endl;
+        out << "9,10,just strings" << std::endl;
+    }
+    size_t bad_lines = 1;
+    auto num_errors = 0;
+
+    auto [p, _] = make_parser<buffer_mode, ErrorMode, ss::multiline,
+                              ss::escape<'\\'>, ss::quote<'"'>>(f.name);
+    std::vector<X> i;
+
+    while (!p.eof()) {
+        try {
+            auto a = p.template get_next<int, double, std::string>();
+            if (p.valid()) {
+                i.emplace_back(ss::to_object<X>(a));
+            } else {
+                ++num_errors;
+            }
+        } catch (const std::exception& e) {
+            ++num_errors;
+        }
+    }
+
+    CHECK(bad_lines == num_errors);
+
+    std::vector<X> data = {{1, 2, "just\n\nstrings"},
+#ifndef _WIN32
+                           {3, 4, "just\r\nsome\r\n\n\nstrings"},
+#else
+                           {3, 4, "just\nsome\n\n\nstrings"},
+#endif
+                           {9, 10, "just strings"}};
+
+    for (auto& [_, __, s] : i) {
+        update_if_crlf(s);
+    }
+    CHECK_EQ(i, data);
+}

test/test_parser1_3.cpp

@@ -0,0 +1,313 @@
+#include "test_parser1.hpp"
+
+TEST_CASE_TEMPLATE("test multiline restricted", T, ParserOptionCombinations) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+
+    unique_file_name f{"multiline_restricted"};
+    {
+        std::ofstream out{f.name};
+        out << "1,2,\"just\n\nstrings\"" << std::endl;
+#ifndef _WIN32
+        out << "3,4,\"ju\n\r\n\nnk\"" << std::endl;
+        out << "5,6,just\\\n\\\r\nstrings" << std::endl;
+#else
+        out << "3,4,\"ju\n\n\nnk\"" << std::endl;
+        out << "5,6,just\\\n\\\nstrings" << std::endl;
+#endif
+        out << "7,8,ju\\\n\\\n\\\nnk" << std::endl;
+        out << "9,10,\"just\\\n\nstrings\"" << std::endl;
+        out << "11,12,\"ju\\\n|\n\n\n\n\nk\"" << std::endl;
+        out << "13,14,\"ju\\\n\\\n15,16\"\\\n\\\\\n\nnk\"" << std::endl;
+        out << "17,18,\"ju\\\n\\\n\\\n\\\\\n\nnk\"" << std::endl;
+        out << "19,20,just strings" << std::endl;
+    }
+    auto bad_lines = 15;
+    auto num_errors = 0;
+
+    auto [p, _] =
+        make_parser<buffer_mode, ErrorMode, ss::multiline_restricted<2>,
+                    ss::quote<'"'>, ss::escape<'\\'>>(f.name, ",");
+    std::vector<X> i;
+
+    while (!p.eof()) {
+        try {
+            auto a = p.template get_next<int, double, std::string>();
+            if (p.valid()) {
+                i.emplace_back(ss::to_object<X>(a));
+            } else {
+                ++num_errors;
+            }
+        } catch (const std::exception& e) {
+            ++num_errors;
+        }
+    }
+
+    CHECK(bad_lines == num_errors);
+
+    std::vector<X> data = {{1, 2, "just\n\nstrings"},
+#ifndef _WIN32
+                           {5, 6, "just\n\r\nstrings"},
+#else
+                           {5, 6, "just\n\nstrings"},
+#endif
+                           {9, 10, "just\n\nstrings"},
+                           {19, 20, "just strings"}};
+
+    for (auto& [_, __, s] : i) {
+        update_if_crlf(s);
+    }
+
+    if (i.size() != data.size()) {
+        CHECK_EQ(i.size(), data.size());
+    }
+
+    CHECK_EQ(i, data);
+}
+
+template <typename T, typename... Ts>
+void test_unterminated_line(const std::vector<std::string>& lines,
+                            size_t bad_line) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+
+    unique_file_name f{"unterminated_line"};
+    std::ofstream out{f.name};
+    for (const auto& line : lines) {
+        out << line << std::endl;
+    }
+    out.close();
+
+    auto [p, _] = make_parser<buffer_mode, ErrorMode, Ts...>(f.name);
+    size_t line = 0;
+    while (!p.eof()) {
+        auto command = [&p = p] {
+            p.template get_next<int, double, std::string>();
+        };
+
+        if (line == bad_line) {
+            expect_error_on_command(p, command);
+            break;
+        } else {
+            command();
+            CHECK(p.valid());
+            ++line;
+        }
+    }
+}
+
+TEST_CASE_TEMPLATE("parser test csv on multiline with errors", T,
+                   ParserOptionCombinations) {
+    using multiline = ss::multiline_restricted<3>;
+    using escape = ss::escape<'\\'>;
+    using quote = ss::quote<'"'>;
+
+    // unterminated escape
+    {
+        const std::vector<std::string> lines{"1,2,just\\"};
+        test_unterminated_line<T, multiline, escape>(lines, 0);
+        test_unterminated_line<T, multiline, escape, quote>(lines, 0);
+    }
+
+    {
+        const std::vector<std::string> lines{"1,2,just\\", "9,8,second"};
+        test_unterminated_line<T, multiline, escape>(lines, 0);
+        test_unterminated_line<T, multiline, escape, quote>(lines, 0);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first", "1,2,just\\"};
+        test_unterminated_line<T, multiline, escape>(lines, 1);
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first", "1,2,just\\",
+                                             "3,4,third"};
+        test_unterminated_line<T, multiline, escape>(lines, 1);
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first",
+                                             "1,2,just\\\nstrings\\",
+                                             "3,4,th\\\nird"};
+        test_unterminated_line<T, multiline, escape>(lines, 1);
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first", "3,4,second",
+                                             "1,2,just\\"};
+        test_unterminated_line<T, multiline, escape>(lines, 2);
+        test_unterminated_line<T, multiline, escape, quote>(lines, 2);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,\\first", "3,4,second",
+                                             "1,2,jus\\t\\"};
+        test_unterminated_line<T, multiline, escape>(lines, 2);
+        test_unterminated_line<T, multiline, escape, quote>(lines, 2);
+    }
+
+    // unterminated quote
+    {
+        const std::vector<std::string> lines{"1,2,\"just"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 0);
+        test_unterminated_line<T, multiline, quote>(lines, 0);
+    }
+
+    {
+        const std::vector<std::string> lines{"1,2,\"just", "9,8,second"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 0);
+        test_unterminated_line<T, multiline, quote>(lines, 0);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first", "1,2,\"just"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+        test_unterminated_line<T, multiline, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first", "1,2,\"just",
+                                             "3,4,th\\,ird"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+        test_unterminated_line<T, multiline, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first", "3,4,second",
+                                             "1,2,\"just"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 2);
+        test_unterminated_line<T, multiline, quote>(lines, 2);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,\"first\"",
+                                             "\"3\",4,\"sec,ond\"",
+                                             "1,2,\"ju\"\"st"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 2);
+        test_unterminated_line<T, multiline, quote>(lines, 2);
+    }
+
+    // unterminated quote and escape
+    {
+        const std::vector<std::string> lines{"1,2,\"just\\"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 0);
+        test_unterminated_line<T, multiline, escape, quote>(lines, 0);
+    }
+
+    {
+        const std::vector<std::string> lines{"1,2,\"just\\\n\\"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 0);
+    }
+
+    {
+        const std::vector<std::string> lines{"1,2,\"just\n\\"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 0);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first", "1,2,\"just\n\\"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first", "1,2,\"just\n\\",
+                                             "4,3,thrid"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,f\\\nirst", "1,2,\"just\n\\",
+                                             "4,3,thrid"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,\"f\ni\nrst\"",
+                                             "1,2,\"just\n\\", "4,3,thrid"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    // multiline limmit reached escape
+    {
+        const std::vector<std::string> lines{"1,2,\\\n\\\n\\\n\\\njust"};
+        test_unterminated_line<T, multiline, escape>(lines, 0);
+        test_unterminated_line<T, multiline, escape, quote>(lines, 0);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first",
+                                             "1,2,\\\n\\\n\\\n\\\njust"};
+        test_unterminated_line<T, multiline, escape>(lines, 1);
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,fi\\\nrs\\\nt",
+                                             "1,2,\\\n\\\n\\\n\\\njust"};
+        test_unterminated_line<T, multiline, escape>(lines, 1);
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first",
+                                             "1,2,\\\n\\\n\\\n\\\njust",
+                                             "4,3,third"};
+        test_unterminated_line<T, multiline, escape>(lines, 1);
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    // multiline limmit reached quote
+    {
+        const std::vector<std::string> lines{"1,2,\"\n\n\n\n\njust\""};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 0);
+        test_unterminated_line<T, multiline, quote>(lines, 0);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first",
+                                             "1,2,\"\n\n\n\n\njust\""};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+        test_unterminated_line<T, multiline, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,\"fir\nst\"",
+                                             "1,2,\"\n\n\n\n\njust\""};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+        test_unterminated_line<T, multiline, quote>(lines, 1);
+    }
+
+    // multiline limmit reached quote and escape
+    {
+        const std::vector<std::string> lines{"1,2,\"\\\n\n\\\n\\\n\\\njust"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 0);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,first",
+                                             "1,2,\"\\\n\n\\\n\\\n\\\njust"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,fi\\\nrst",
+                                             "1,2,\"\\\n\n\\\n\\\n\\\njust"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,\"fi\nrst\"",
+                                             "1,2,\"\\\n\n\\\n\\\n\\\njust"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+
+    {
+        const std::vector<std::string> lines{"9,8,\"fi\nr\\\nst\"",
+                                             "1,2,\"\\\n\n\\\n\\\n\\\njust"};
+        test_unterminated_line<T, multiline, escape, quote>(lines, 1);
+    }
+}

test/test_parser1_4.cpp

@@ -0,0 +1,471 @@
+#include "test_parser1.hpp"
+
+template <typename T, typename Tuple>
+struct has_type;
+
+template <typename T, typename... Us>
+struct has_type<T, std::tuple<Us...>>
+    : std::disjunction<std::is_same<T, Us>...> {};
+
+template <typename T, typename... Ts>
+static void test_fields(const std::string file_name, const std::vector<X>& data,
+                        const std::vector<std::string>& fields) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+    using CaseType = std::tuple<Ts...>;
+
+    auto [p, _] = make_parser<buffer_mode, ErrorMode>(file_name, ",");
+    CHECK_FALSE(p.field_exists("Unknown"));
+    p.use_fields(fields);
+    std::vector<CaseType> i;
+
+    for (const auto& a : p.template iterate<CaseType>()) {
+        i.push_back(a);
+    }
+
+    CHECK_EQ(i.size(), data.size());
+    for (size_t j = 0; j < i.size(); ++j) {
+        if constexpr (has_type<int, CaseType>::value) {
+            CHECK_EQ(std::get<int>(i[j]), data[j].i);
+        }
+        if constexpr (has_type<double, CaseType>::value) {
+            CHECK_EQ(std::get<double>(i[j]), data[j].d);
+        }
+        if constexpr (has_type<std::string, CaseType>::value) {
+            CHECK_EQ(std::get<std::string>(i[j]), data[j].s);
+        }
+    }
+}
+
+TEST_CASE_TEMPLATE("test various cases with header", T,
+                   ParserOptionCombinations) {
+    unique_file_name f{"various_cases_with_header"};
+    constexpr static auto Int = "Int";
+    constexpr static auto Dbl = "Double";
+    constexpr static auto Str = "String";
+    using str = std::string;
+
+    std::vector<std::string> header{Int, Dbl, Str};
+
+    std::vector<X> data = {{1, 2, "x"}, {3, 4, "y"},  {5, 6, "z"},
+                           {7, 8, "u"}, {9, 10, "v"}, {11, 12, "w"}};
+
+    make_and_write(f.name, data, header);
+    const auto& o = f.name;
+    const auto& d = data;
+
+    {
+        ss::parser<ss::string_error> p{f.name, ","};
+        std::vector<X> i;
+
+        for (const auto& a : p.iterate<int, double, std::string>()) {
+            i.emplace_back(ss::to_object<X>(a));
+        }
+
+        CHECK_NE(i, data);
+    }
+
+    {
+        ss::parser<ss::string_error> p{f.name, ","};
+        std::vector<X> i;
+
+        p.ignore_next();
+        for (const auto& a : p.iterate<int, double, std::string>()) {
+            i.emplace_back(ss::to_object<X>(a));
+        }
+
+        CHECK_EQ(i, data);
+    }
+
+    {
+        ss::parser<ss::ignore_header> p{f.name, ","};
+        std::vector<X> i;
+
+        for (const auto& a : p.iterate<int, double, std::string>()) {
+            i.emplace_back(ss::to_object<X>(a));
+        }
+
+        CHECK_EQ(i, data);
+    }
+
+    {
+        ss::parser<ss::ignore_header, ss::string_error> p{f.name, ","};
+        p.use_fields(Int, Dbl, Str);
+        CHECK_FALSE(p.valid());
+    }
+
+    {
+        ss::parser<ss::ignore_header, ss::string_error> p{f.name, ","};
+        CHECK_FALSE(p.field_exists("Unknown"));
+
+        p.use_fields(Int, "Unknown");
+        CHECK_FALSE(p.valid());
+    }
+
+    {
+        ss::parser<ss::ignore_header, ss::string_error> p{f.name, ","};
+        p.use_fields(Int, Int);
+        CHECK_FALSE(p.valid());
+    }
+
+    {
+        ss::parser<ss::string_error> p{f.name, ","};
+        p.use_fields(Int, Dbl);
+
+        {
+            auto [int_, double_] = p.get_next<int, double>();
+            CHECK_EQ(int_, data[0].i);
+            CHECK_EQ(double_, data[0].d);
+        }
+
+        p.use_fields(Dbl, Int);
+
+        {
+            auto [double_, int_] = p.get_next<double, int>();
+            CHECK_EQ(int_, data[1].i);
+            CHECK_EQ(double_, data[1].d);
+        }
+
+        p.use_fields(Str);
+
+        {
+            auto string_ = p.get_next<std::string>();
+            CHECK_EQ(string_, data[2].s);
+        }
+
+        p.use_fields(Str, Int, Dbl);
+
+        {
+            auto [string_, int_, double_] =
+                p.get_next<std::string, int, double>();
+            CHECK_EQ(double_, data[3].d);
+            CHECK_EQ(int_, data[3].i);
+            CHECK_EQ(string_, data[3].s);
+        }
+    }
+
+    /*  python used to generate permutations
+        import itertools
+
+        header = {'str': 'Str',
+                 'double': 'Dbl',
+                 'int': 'Int'}
+
+        keys = ['str', 'int', 'double']
+
+        for r in range (1, 3):
+            combinations = list(itertools.permutations(keys, r = r))
+
+            for combination in combinations:
+                template_params = []
+                arg_params = []
+                for type in combination:
+                    template_params.append(type)
+                    arg_params.append(header[type])
+                call = 'testFields<' + ', '.join(template_params) + \
+                    '>(o, d, {' + ', '.join(arg_params) + '});'
+                print(call)
+        */
+
+    test_fields<T, str>(o, d, {Str});
+    test_fields<T, int>(o, d, {Int});
+    test_fields<T, double>(o, d, {Dbl});
+    test_fields<T, str, int>(o, d, {Str, Int});
+    test_fields<T, str, double>(o, d, {Str, Dbl});
+    test_fields<T, int, str>(o, d, {Int, Str});
+    test_fields<T, int, double>(o, d, {Int, Dbl});
+    test_fields<T, double, str>(o, d, {Dbl, Str});
+    test_fields<T, double, int>(o, d, {Dbl, Int});
+    test_fields<T, str, int, double>(o, d, {Str, Int, Dbl});
+    test_fields<T, str, double, int>(o, d, {Str, Dbl, Int});
+    test_fields<T, int, str, double>(o, d, {Int, Str, Dbl});
+    test_fields<T, int, double, str>(o, d, {Int, Dbl, Str});
+    test_fields<T, double, str, int>(o, d, {Dbl, Str, Int});
+    test_fields<T, double, int, str>(o, d, {Dbl, Int, Str});
+}
+
+template <typename T>
+void test_invalid_fields(const std::vector<std::string>& lines,
+                         const std::vector<std::string>& fields) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+
+    unique_file_name f{"invalid_fields"};
+    {
+        std::ofstream out{f.name};
+        for (const auto& line : lines) {
+            out << line << std::endl;
+        }
+    }
+
+    {
+        // No fields specified
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        auto command = [&p = p] { p.use_fields(); };
+        expect_error_on_command(p, command);
+    }
+
+    {
+        // Unknown field
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        auto command = [&p = p] { p.use_fields("Unknown"); };
+        expect_error_on_command(p, command);
+    }
+
+    {
+        // Field used multiple times
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        auto command = [&p = p, &fields = fields] {
+            p.use_fields(fields.at(0), fields.at(0));
+        };
+        if (!fields.empty()) {
+            expect_error_on_command(p, command);
+        }
+    }
+
+    {
+        // Mapping out of range
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        auto command = [&p = p, &fields = fields] {
+            p.use_fields(fields.at(0));
+            p.template get_next<std::string, std::string>();
+        };
+        if (!fields.empty()) {
+            expect_error_on_command(p, command);
+        }
+    }
+
+    {
+        // Invalid header
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        auto command = [&p = p, &fields = fields] { p.use_fields(fields); };
+
+        if (!fields.empty()) {
+            // Pass if there are no duplicates, fail otherwise
+            if (std::unordered_set<std::string>{fields.begin(), fields.end()}
+                    .size() != fields.size()) {
+                expect_error_on_command(p, command);
+            } else {
+                command();
+                CHECK(p.valid());
+                if (!p.valid()) {
+                    if constexpr (T::StringError) {
+                        std::cout << p.error_msg() << std::endl;
+                    }
+                }
+            }
+        }
+    }
+}
+
+TEST_CASE_TEMPLATE("test invalid fheader fields usage", T,
+                   ParserOptionCombinations) {
+    test_invalid_fields<T>({}, {});
+
+    test_invalid_fields<T>({"Int"}, {"Int"});
+    test_invalid_fields<T>({"Int", "1"}, {"Int"});
+    test_invalid_fields<T>({"Int", "1", "2"}, {"Int"});
+
+    test_invalid_fields<T>({"Int,String"}, {"Int", "String"});
+    test_invalid_fields<T>({"Int,String", "1,hi"}, {"Int", "String"});
+    test_invalid_fields<T>({"Int,String", "2,hello"}, {"Int", "String"});
+
+    test_invalid_fields<T>({"Int,String,Double"}, {"Int", "String", "Double"});
+    test_invalid_fields<T>({"Int,String,Double", "1,hi,2.34"},
+                           {"Int", "String", "Double"});
+    test_invalid_fields<T>({"Int,String,Double", "1,hi,2.34", "2,hello,3.45"},
+                           {"Int", "String", "Double"});
+
+    test_invalid_fields<T>({"Int,Int,Int"}, {"Int", "Int", "Int"});
+    test_invalid_fields<T>({"Int,Int,Int", "1,2,3"}, {"Int", "Int", "Int"});
+
+    test_invalid_fields<T>({"Int,String,Int"}, {"Int", "String", "Int"});
+    test_invalid_fields<T>({"Int,String,Int", "1,hi,3"},
+                           {"Int", "String", "Int"});
+}
+
+TEST_CASE_TEMPLATE("test invalid rows with header", T,
+                   ParserOptionCombinations) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+
+    unique_file_name f{"invalid rows with header"};
+    {
+        std::ofstream out{f.name};
+        out << "Int,String,Double" << std::endl;
+        out << "1,line1,2.34" << std::endl;
+        out << "2,line2" << std::endl;
+        out << "3,line3,67.8" << std::endl;
+        out << "4,line4,67.8,9" << std::endl;
+        out << "5,line5,9.10" << std::endl;
+        out << "six,line6,10.11" << std::endl;
+    }
+
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name);
+
+        p.use_fields("Int", "String", "Double");
+        using data = std::tuple<int, std::string, double>;
+        std::vector<data> i;
+
+        CHECK(p.valid());
+
+        while (!p.eof()) {
+            try {
+                const auto& t = p.template get_next<data>();
+                if (p.valid()) {
+                    i.push_back(t);
+                }
+            } catch (const ss::exception&) {
+                continue;
+            }
+        }
+
+        std::vector<data> expected = {{1, "line1", 2.34},
+                                      {3, "line3", 67.8},
+                                      {5, "line5", 9.10}};
+        CHECK_EQ(i, expected);
+    }
+
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name);
+
+        p.use_fields("Double", "Int");
+        using data = std::tuple<double, int>;
+        std::vector<data> i;
+
+        CHECK(p.valid());
+
+        while (!p.eof()) {
+            try {
+                const auto& t = p.template get_next<data>();
+                if (p.valid()) {
+                    i.push_back(t);
+                }
+            } catch (const ss::exception&) {
+                continue;
+            }
+        }
+
+        std::vector<data> expected = {{2.34, 1}, {67.8, 3}, {9.10, 5}};
+        CHECK_EQ(i, expected);
+    }
+
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name);
+
+        p.use_fields("String", "Double");
+        using data = std::tuple<std::string, double>;
+        std::vector<data> i;
+
+        CHECK(p.valid());
+
+        while (!p.eof()) {
+            try {
+                const auto& t = p.template get_next<data>();
+                if (p.valid()) {
+                    i.push_back(t);
+                }
+            } catch (const ss::exception&) {
+                continue;
+            }
+        }
+
+        std::vector<data> expected = {{"line1", 2.34},
+                                      {"line3", 67.8},
+                                      {"line5", 9.10},
+                                      {"line6", 10.11}};
+        CHECK_EQ(i, expected);
+    }
+}
+
+template <typename T>
+void test_ignore_empty(const std::vector<X>& data) {
+    constexpr auto buffer_mode = T::BufferMode::value;
+    using ErrorMode = typename T::ErrorMode;
+
+    unique_file_name f{"ignore_empty"};
+    make_and_write(f.name, data);
+
+    std::vector<X> expected;
+    for (const auto& d : data) {
+        if (d.s != X::empty) {
+            expected.push_back(d);
+        }
+    }
+
+    {
+        auto [p, _] =
+            make_parser<buffer_mode, ErrorMode, ss::ignore_empty>(f.name, ",");
+
+        std::vector<X> i;
+        for (const auto& a : p.template iterate<X>()) {
+            i.push_back(a);
+        }
+
+        CHECK_EQ(i, expected);
+    }
+
+    {
+        auto [p, _] = make_parser<buffer_mode, ErrorMode>(f.name, ",");
+        std::vector<X> i;
+        size_t n = 0;
+        while (!p.eof()) {
+            try {
+                ++n;
+                const auto& a = p.template get_next<X>();
+                if (data.at(n - 1).s == X::empty) {
+                    CHECK_FALSE(p.valid());
+                    continue;
+                }
+                i.push_back(a);
+            } catch (...) {
+                CHECK_EQ(data.at(n - 1).s, X::empty);
+            }
+        }
+
+        CHECK_EQ(i, expected);
+    }
+}
+
+TEST_CASE_TEMPLATE("test various cases with empty lines", T,
+                   ParserOptionCombinations) {
+    test_ignore_empty<T>(
+        {{1, 2, "x"}, {3, 4, "y"}, {9, 10, "v"}, {11, 12, "w"}});
+
+    test_ignore_empty<T>(
+        {{1, 2, X::empty}, {3, 4, "y"}, {9, 10, "v"}, {11, 12, "w"}});
+
+    test_ignore_empty<T>(
+        {{1, 2, "x"}, {3, 4, "y"}, {9, 10, "v"}, {11, 12, X::empty}});
+
+    test_ignore_empty<T>(
+        {{1, 2, "x"}, {5, 6, X::empty}, {9, 10, "v"}, {11, 12, "w"}});
+
+    test_ignore_empty<T>(
+        {{1, 2, X::empty}, {5, 6, X::empty}, {9, 10, "v"}, {11, 12, "w"}});
+
+    test_ignore_empty<T>(
+        {{1, 2, X::empty}, {3, 4, "y"}, {9, 10, "v"}, {11, 12, X::empty}});
+
+    test_ignore_empty<T>(
+        {{1, 2, "x"}, {3, 4, "y"}, {9, 10, X::empty}, {11, 12, X::empty}});
+
+    test_ignore_empty<T>(
+        {{1, 2, X::empty}, {3, 4, "y"}, {9, 10, X::empty}, {11, 12, X::empty}});
+
+    test_ignore_empty<T>({{1, 2, X::empty},
+                          {3, 4, X::empty},
+                          {9, 10, X::empty},
+                          {11, 12, X::empty}});
+
+    test_ignore_empty<T>(
+        {{1, 2, "x"}, {3, 4, X::empty}, {9, 10, X::empty}, {11, 12, X::empty}});
+
+    test_ignore_empty<T>(
+        {{1, 2, X::empty}, {3, 4, X::empty}, {9, 10, X::empty}, {11, 12, "w"}});
+
+    test_ignore_empty<T>({{11, 12, X::empty}});
+
+    test_ignore_empty<T>({});
+}

test/test_parser2.hpp

@@ -257,9 +257,12 @@ std::vector<std::string> generate_csv_data(const std::vector<field>& data,
 }
 
 [[maybe_unused]] void write_to_file(const std::vector<std::string>& data,
-                   const std::string& delim, const std::string& file_name) {
+                                    const std::string& delim,
+                                    const std::string& file_name,
+                                    bool add_new_line = true) {
     std::ofstream out{file_name, std::ios_base::app};
     std::string line;
+
     for (size_t i = 0; i < data.size(); ++i) {
         line += data[i];
         if (i != data.size() - 1) {
@@ -267,7 +270,10 @@ std::vector<std::string> generate_csv_data(const std::vector<field>& data,
         }
     }
 
-    out << line << std::endl;
+    out << line;
+    if (add_new_line) {
+        out << std::endl;
+    }
 }
 
 #define CHECK_EQ_CRLF(V1, V2)                                                  \
@@ -299,7 +305,7 @@ std::vector<std::string> generate_csv_data(const std::vector<field>& data,
         CHECK(V1 == V2);                                                       \
     }
 
-template <typename... Ts>
+template <bool buffer_mode, typename... Ts>
 void test_data_combinations(const std::vector<column>& input_data,
                             const std::string& delim, bool include_header) {
     using setup = ss::setup<Ts...>;
@@ -308,7 +314,7 @@ void test_data_combinations(const std::vector<column>& input_data,
         return;
     }
 
-    unique_file_name f{"test_parser2" + std::string{SEGMENT_NAME}};
+    unique_file_name f{"parser_data_combinations" + std::string{SEGMENT_NAME}};
     std::vector<std::vector<field>> expected_data;
     std::vector<std::string> header;
     std::vector<field> field_header;
@@ -329,8 +335,12 @@ void test_data_combinations(const std::vector<column>& input_data,
 
     if (include_header) {
         auto header_data = generate_csv_data<Ts...>(field_header, delim);
+        if (input_data.size() == 0 && rand() % 10 == 0) {
+            write_to_file(header_data, delim, f.name, false);
+        } else {
             write_to_file(header_data, delim, f.name);
         }
+    }
 
     std::vector<int> layout;
     size_t n = 1 + rng.rand() % 5;
@@ -354,15 +364,12 @@ void test_data_combinations(const std::vector<column>& input_data,
 
         expected_data.push_back(raw_data);
         auto data = generate_csv_data<Ts...>(raw_data, delim);
-        write_to_file(data, delim, f.name);
 
-        /*
+        if (i + 1 == n && rand() % 10 == 0) {
-        std::cout << "[.";
+            write_to_file(data, delim, f.name, false);
-        for (const auto& el : data) {
+        } else {
-            std::cout << el << '.';
+            write_to_file(data, delim, f.name);
         }
-        std::cout << "]" << std::endl;
-        */
     }
 
     auto layout_combinations = include_header && !setup::ignore_header
@@ -388,7 +395,7 @@ void test_data_combinations(const std::vector<column>& input_data,
     }
 
     for (const auto& layout : unique_layout_combinations) {
-        ss::parser<setup> p{f.name, delim};
+        auto [p, _] = make_parser<buffer_mode, setup>(f.name, delim);
 
         if (include_header && !setup::ignore_header) {
             std::vector<std::string> fields;
@@ -409,7 +416,7 @@ void test_data_combinations(const std::vector<column>& input_data,
             REQUIRE(p.valid());
         }
 
-        auto check_error = [&p] {
+        auto check_error = [&p = p] {
             CHECK(p.valid());
             if (!p.valid()) {
                 if constexpr (setup::string_error) {
@@ -426,7 +433,6 @@ void test_data_combinations(const std::vector<column>& input_data,
                     auto s0 = p.template get_next<std::string>();
                     if (i < n) {
                         check_error();
-                        // std::cout << s0 << std::endl;
                         CHECK_EQ_CRLF(s0, expected_data[i][layout[0]].value);
                     } else {
                         CHECK(p.eof());
@@ -439,7 +445,6 @@ void test_data_combinations(const std::vector<column>& input_data,
                         p.template get_next<std::string, std::string>();
                     if (i < n) {
                         check_error();
-                        // std::cout << s0 << ' ' << s1 << std::endl;
                         CHECK_EQ_CRLF(s0, expected_data[i][layout[0]].value);
                         CHECK_EQ_CRLF(s1, expected_data[i][layout[1]].value);
                     } else {
@@ -454,8 +459,6 @@ void test_data_combinations(const std::vector<column>& input_data,
                                             std::string>();
                     if (i < n) {
                         check_error();
-                        // std::cout << s0 << ' ' << s1 << ' ' << s2 <<
-                        // std::endl;
                         CHECK_EQ_CRLF(s0, expected_data[i][layout[0]].value);
                         CHECK_EQ_CRLF(s1, expected_data[i][layout[1]].value);
                         CHECK_EQ_CRLF(s2, expected_data[i][layout[2]].value);
@@ -471,10 +474,6 @@ void test_data_combinations(const std::vector<column>& input_data,
                                             std::string, std::string>();
                     if (i < n) {
                         check_error();
-                        /*
-                        std::cout << s0 << ' ' << s1 << ' ' << s2 << ' ' << s3
-                                  << std::endl;
-                                  */
                         CHECK_EQ_CRLF(s0, expected_data[i][layout[0]].value);
                         CHECK_EQ_CRLF(s1, expected_data[i][layout[1]].value);
                         CHECK_EQ_CRLF(s2, expected_data[i][layout[2]].value);
@@ -492,9 +491,6 @@ void test_data_combinations(const std::vector<column>& input_data,
                                             std::string>();
                     if (i < n) {
                         check_error();
-                        // std::cout << s0 << ' ' << s1 << ' ' << s2 << ' ' <<
-                        // s3
-                        //  << ' ' << s4 << std::endl;
                         CHECK_EQ_CRLF(s0, expected_data[i][layout[0]].value);
                         CHECK_EQ_CRLF(s1, expected_data[i][layout[1]].value);
                         CHECK_EQ_CRLF(s2, expected_data[i][layout[2]].value);
@@ -570,8 +566,14 @@ void test_option_combinations() {
                  {columns0, columns1, columns2, columns3, columns4, columns5,
                   columns6, columns7}) {
                 try {
-                    test_data_combinations<Ts...>(columns, delimiter, false);
+                    test_data_combinations<false, Ts...>(columns, delimiter,
-                    test_data_combinations<Ts...>(columns, delimiter, true);
+                                                         false);
+                    test_data_combinations<false, Ts...>(columns, delimiter,
+                                                         true);
+                    test_data_combinations<true, Ts...>(columns, delimiter,
+                                                        false);
+                    test_data_combinations<true, Ts...>(columns, delimiter,
+                                                        true);
                 } catch (std::exception& e) {
                     std::cout << typeid(ss::parser<Ts...>).name() << std::endl;
                     FAIL_CHECK(std::string{e.what()});
@@ -616,6 +618,7 @@ void test_option_combinations3() {
 
 } /* namespace */
 
+// Tests split into multiple compilation units
 #if 0
 
 TEST_CASE("parser test various cases version 2 segment 1") {
@@ -627,25 +630,33 @@ TEST_CASE("parser test various cases version 2 segment 1") {
     using multiline_r = ss::multiline_restricted<10>;
     using trimr = ss::trim_right<' '>;
     using triml = ss::trim_left<' '>;
+    using trim = ss::trim<' '>;
 
     // segment 1
     test_option_combinations3<>();
     test_option_combinations3<escape>();
-    test_option_combinations3<quote>();
 
     // segment 2
+    test_option_combinations3<quote>();
     test_option_combinations3<escape, quote>();
+
+    // segment 3
     test_option_combinations3<escape, multiline>();
     test_option_combinations3<quote, multiline>();
 
-    // segment 3
+    // segment 4
     test_option_combinations3<escape, quote, multiline>();
     test_option_combinations3<escape, quote, multiline_r>();
 
-    // segment 4
+    // segment 5
     test_option_combinations<escape, quote, multiline, triml>();
     test_option_combinations<escape, quote, multiline, trimr>();
+
+    // segment 6
+    test_option_combinations3<escape, quote, multiline>();
+    test_option_combinations3<escape, quote, multiline, trim>();
 #else
+
     test_option_combinations3<escape, quote, multiline>();
 #endif
 }

test/test_parser2_1.cpp

@@ -3,12 +3,10 @@
 
 TEST_CASE("parser test various cases version 2 segment 1") {
 #ifdef CMAKE_GITHUB_CI
-    using quote = ss::quote<'"'>;
     using escape = ss::escape<'\\'>;
 
     test_option_combinations3<>();
     test_option_combinations3<escape>();
-    test_option_combinations3<quote>();
 #endif
 }
 

test/test_parser2_2.cpp

@@ -5,11 +5,9 @@ TEST_CASE("parser test various cases version 2 segment 2") {
 #ifdef CMAKE_GITHUB_CI
     using quote = ss::quote<'"'>;
     using escape = ss::escape<'\\'>;
-    using multiline = ss::multiline;
 
+    test_option_combinations3<quote>();
     test_option_combinations3<escape, quote>();
-    test_option_combinations3<escape, multiline>();
-    test_option_combinations3<quote, multiline>();
 #endif
 }
 

test/test_parser2_3.cpp

@@ -6,10 +6,9 @@ TEST_CASE("parser test various cases version 2 segment 3") {
     using quote = ss::quote<'"'>;
     using escape = ss::escape<'\\'>;
     using multiline = ss::multiline;
-    using multiline_r = ss::multiline_restricted<10>;
 
-    test_option_combinations3<escape, quote, multiline>();
+    test_option_combinations3<escape, multiline>();
-    test_option_combinations3<escape, quote, multiline_r>();
+    test_option_combinations3<quote, multiline>();
 #endif
 }
 

test/test_parser2_4.cpp

@@ -2,18 +2,14 @@
 #include "test_parser2.hpp"
 
 TEST_CASE("parser test various cases version 2 segment 4") {
+#ifdef CMAKE_GITHUB_CI
     using quote = ss::quote<'"'>;
     using escape = ss::escape<'\\'>;
     using multiline = ss::multiline;
+    using multiline_r = ss::multiline_restricted<10>;
 
-#ifdef CMAKE_GITHUB_CI
-    using trimr = ss::trim_right<' '>;
-    using triml = ss::trim_left<' '>;
-
-    test_option_combinations<escape, quote, multiline, triml>();
-    test_option_combinations<escape, quote, multiline, trimr>();
-#else
     test_option_combinations3<escape, quote, multiline>();
+    test_option_combinations3<escape, quote, multiline_r>();
 #endif
 }
 

test/test_parser2_5.cpp

@@ -0,0 +1,16 @@
+#define SEGMENT_NAME "segment5"
+#include "test_parser2.hpp"
+
+TEST_CASE("parser test various cases version 2 segment 5") {
+#ifdef CMAKE_GITHUB_CI
+    using quote = ss::quote<'"'>;
+    using escape = ss::escape<'\\'>;
+    using multiline = ss::multiline;
+    using trimr = ss::trim_right<' '>;
+    using triml = ss::trim_left<' '>;
+
+    test_option_combinations<escape, quote, multiline, triml>();
+    test_option_combinations<escape, quote, multiline, trimr>();
+#endif
+}
+

test/test_parser2_6.cpp

@@ -0,0 +1,11 @@
+#define SEGMENT_NAME "segment6"
+#include "test_parser2.hpp"
+
+TEST_CASE("parser test various cases version 2 segment 6") {
+    using quote = ss::quote<'"'>;
+    using escape = ss::escape<'\\'>;
+    using multiline = ss::multiline;
+
+    test_option_combinations3<escape, quote, multiline>();
+}
+