CSV Parser 2.1.2: July 26, 2021 Patch (#177)

* Fix C++-14 compile issues

* CSV Parser should now build with std=c++11 on g++-7.5

* Fixed issues with floating point writing

* Fixed newlines not being escaped

* Update single header

Author: vincentlaucsb

README.md

@@ -60,7 +60,7 @@ In addition to the [Features & Examples](#features--examples) below, a [fully-fl
 
 ## Integration
 
-This library was developed with Microsoft Visual Studio and is compatible with >g++ 6.0 and clang.
+This library was developed with Microsoft Visual Studio and is compatible with >g++ 7.5 and clang.
 All of the code required to build this library, aside from the C++ standard library, is contained under `include/`.
 
 ### C++ Version
@@ -342,6 +342,7 @@ stringstream ss; // Can also use ofstream, etc.
 auto writer = make_csv_writer(ss);
 // auto writer = make_tsv_writer(ss);               // For tab-separated files
 // DelimWriter<stringstream, '|', '"'> writer(ss);  // Your own custom format
+// set_decimal_places(2);                           // How many places after the decimal will be written for floats
 
 writer << vector<string>({ "A", "B", "C" })
     << deque<string>({ "I'm", "too", "tired" })

include/csv.hpp

@@ -1,5 +1,5 @@
 /*
-CSV for C++, version 2.1.0
+CSV for C++, version 2.1.2
 https://github.com/vincentlaucsb/csv-parser
 
 MIT License

include/internal/basic_csv_parser.hpp

@@ -27,7 +27,7 @@ namespace csv {
          *  ASCII number for a character and, v[i + 128] labels it according to
          *  the CSVReader::ParseFlags enum
          */
-        HEDLEY_CONST CONSTEXPR ParseFlagMap make_parse_flags(char delimiter) {
+        HEDLEY_CONST CONSTEXPR_17 ParseFlagMap make_parse_flags(char delimiter) {
             std::array<ParseFlags, 256> ret = {};
             for (int i = -128; i < 128; i++) {
                 const int arr_idx = i + 128;
@@ -48,7 +48,7 @@ namespace csv {
          *  ASCII number for a character and, v[i + 128] labels it according to
          *  the CSVReader::ParseFlags enum
          */
-        HEDLEY_CONST CONSTEXPR ParseFlagMap make_parse_flags(char delimiter, char quote_char) {
+        HEDLEY_CONST CONSTEXPR_17 ParseFlagMap make_parse_flags(char delimiter, char quote_char) {
             std::array<ParseFlags, 256> ret = make_parse_flags(delimiter);
             ret[(size_t)quote_char + 128] = ParseFlags::QUOTE;
             return ret;
@@ -58,7 +58,7 @@ namespace csv {
          *  ASCII number for a character c and, v[i + 128] is true if
          *  c is a whitespace character
          */
-        HEDLEY_CONST CONSTEXPR WhitespaceMap make_ws_flags(const char* ws_chars, size_t n_chars) {
+        HEDLEY_CONST CONSTEXPR_14 WhitespaceMap make_ws_flags(const char* ws_chars, size_t n_chars) {
             std::array<bool, 256> ret = {};
             for (int i = -128; i < 128; i++) {
                 const int arr_idx = i + 128;
@@ -210,11 +210,11 @@ namespace csv {
             /** Indicate the last block of data has been parsed */
             void end_feed();
 
-            CONSTEXPR ParseFlags parse_flag(const char ch) const noexcept {
+            CONSTEXPR_17 ParseFlags parse_flag(const char ch) const noexcept {
                 return _parse_flags.data()[ch + 128];
             }
 
-            CONSTEXPR ParseFlags compound_parse_flag(const char ch) const noexcept {
+            CONSTEXPR_17 ParseFlags compound_parse_flag(const char ch) const noexcept {
                 return quote_escape_flag(parse_flag(ch), this->quote_escape);
             }
 
@@ -274,7 +274,7 @@ namespace csv {
             /** Where complete rows should be pushed to */
             RowCollection* _records = nullptr;
 
-            CONSTEXPR bool ws_flag(const char ch) const noexcept {
+            CONSTEXPR_17 bool ws_flag(const char ch) const noexcept {
                 return _ws_flags.data()[ch + 128];
             }
 

include/internal/common.hpp

@@ -74,31 +74,41 @@ namespace csv {
 #endif
 
 #ifdef CSV_HAS_CXX17
-#define IF_CONSTEXPR if constexpr
-#define CONSTEXPR_VALUE constexpr
+    #define IF_CONSTEXPR if constexpr
+    #define CONSTEXPR_VALUE constexpr
+
+    #define CONSTEXPR_17 constexpr
 #else
-#define IF_CONSTEXPR if
-#define CONSTEXPR_VALUE const
+    #define IF_CONSTEXPR if
+    #define CONSTEXPR_VALUE const
+
+    #define CONSTEXPR_17 inline
 #endif
 
 #ifdef CSV_HAS_CXX14
     template<bool B, class T = void>
     using enable_if_t = std::enable_if_t<B, T>;
+
+    #define CONSTEXPR_14 constexpr
+    #define CONSTEXPR_VALUE_14 constexpr
 #else
     template<bool B, class T = void>
     using enable_if_t = typename std::enable_if<B, T>::type;
+
+    #define CONSTEXPR_14 inline
+    #define CONSTEXPR_VALUE_14 const
 #endif
 
     // Resolves g++ bug with regard to constexpr methods
     // See: https://stackoverflow.com/questions/36489369/constexpr-non-static-member-function-with-non-constexpr-constructor-gcc-clang-d
 #if defined __GNUC__ && !defined __clang__
-#if (__GNUC__ >= 7 &&__GNUC_MINOR__ >= 2) || (__GNUC__ >= 8)
-#define CONSTEXPR constexpr
-#endif
-#else
-#ifdef CSV_HAS_CXX17
-#define CONSTEXPR constexpr
-#endif
+    #if (__GNUC__ >= 7 &&__GNUC_MINOR__ >= 2) || (__GNUC__ >= 8)
+        #define CONSTEXPR constexpr
+    #endif
+    #else
+        #ifdef CSV_HAS_CXX17
+        #define CONSTEXPR constexpr
+    #endif
 #endif
 
 #ifndef CONSTEXPR

include/internal/csv_format.hpp

@@ -93,13 +93,13 @@ namespace csv {
         }
 
         /** Tells the parser how to handle columns of a different length than the others */
-        CONSTEXPR CSVFormat& variable_columns(VariableColumnPolicy policy = VariableColumnPolicy::IGNORE_ROW) {
+        CONSTEXPR_14 CSVFormat& variable_columns(VariableColumnPolicy policy = VariableColumnPolicy::IGNORE_ROW) {
             this->variable_column_policy = policy;
             return *this;
         }
 
         /** Tells the parser how to handle columns of a different length than the others */
-        CONSTEXPR CSVFormat& variable_columns(bool policy) {
+        CONSTEXPR_14 CSVFormat& variable_columns(bool policy) {
             this->variable_column_policy = (VariableColumnPolicy)policy;
             return *this;
         }

include/internal/csv_reader.hpp

@@ -81,10 +81,10 @@ namespace csv {
             iterator(CSVReader*, CSVRow&&);
 
             /** Access the CSVRow held by the iterator */
-            CONSTEXPR reference operator*() { return this->row; }
+            CONSTEXPR_14 reference operator*() { return this->row; }
 
             /** Return a pointer to the CSVRow the iterator has stopped at */
-            CONSTEXPR pointer operator->() { return &(this->row); }
+            CONSTEXPR_14 pointer operator->() { return &(this->row); }
 
             iterator& operator++();   /**< Pre-increment iterator */
             iterator operator++(int); /**< Post-increment ierator */

include/internal/csv_row.hpp

@@ -253,24 +253,24 @@ namespace csv {
         CONSTEXPR csv::string_view get_sv() const noexcept { return this->sv; }
 
         /** Returns true if field is an empty string or string of whitespace characters */
-        CONSTEXPR bool is_null() noexcept { return type() == DataType::CSV_NULL; }
+        CONSTEXPR_14 bool is_null() noexcept { return type() == DataType::CSV_NULL; }
 
         /** Returns true if field is a non-numeric, non-empty string */
-        CONSTEXPR bool is_str() noexcept { return type() == DataType::CSV_STRING; }
+        CONSTEXPR_14 bool is_str() noexcept { return type() == DataType::CSV_STRING; }
 
         /** Returns true if field is an integer or float */
-        CONSTEXPR bool is_num() noexcept { return type() >= DataType::CSV_INT8; }
+        CONSTEXPR_14 bool is_num() noexcept { return type() >= DataType::CSV_INT8; }
 
         /** Returns true if field is an integer */
-        CONSTEXPR bool is_int() noexcept {
+        CONSTEXPR_14 bool is_int() noexcept {
             return (type() >= DataType::CSV_INT8) && (type() <= DataType::CSV_INT64);
         }
 
         /** Returns true if field is a floating point value */
-        CONSTEXPR bool is_float() noexcept { return type() == DataType::CSV_DOUBLE; };
+        CONSTEXPR_14 bool is_float() noexcept { return type() == DataType::CSV_DOUBLE; };
 
         /** Return the type of the underlying CSV data */
-        CONSTEXPR DataType type() noexcept {
+        CONSTEXPR_14 DataType type() noexcept {
             this->get_value();
             return _type;
         }
@@ -279,7 +279,7 @@ namespace csv {
         long double value = 0;    /**< Cached numeric value */
         csv::string_view sv = ""; /**< A pointer to this field's text */
         DataType _type = DataType::UNKNOWN; /**< Cached data type value */
-        CONSTEXPR void get_value() noexcept {
+        CONSTEXPR_14 void get_value() noexcept {
             /* Check to see if value has been cached previously, if not
              * evaluate it
              */
@@ -419,13 +419,13 @@ namespace csv {
      *           CSVRow is still alive.
      */
     template<>
-    CONSTEXPR csv::string_view CSVField::get<csv::string_view>() {
+    CONSTEXPR_14 csv::string_view CSVField::get<csv::string_view>() {
         return this->sv;
     }
 
     /** Retrieve this field's value as a long double */
     template<>
-    CONSTEXPR long double CSVField::get<long double>() {
+    CONSTEXPR_14 long double CSVField::get<long double>() {
         if (!is_num())
             throw std::runtime_error(internals::ERROR_NAN);
 

include/internal/csv_writer.hpp

@@ -15,6 +15,8 @@
 
 namespace csv {
     namespace internals {
+        static int DECIMAL_PLACES = 5;
+
         /** to_string() for unsigned integers */
         template<typename T,
             csv::enable_if_t<std::is_unsigned<T>::value, int> = 0>
@@ -48,25 +50,52 @@ namespace csv {
             typename T,
             csv::enable_if_t<std::is_floating_point<T>::value, int> = 0
         >
-        inline std::string to_string(T value) {
-            std::string result;
+            inline std::string to_string(T value) {
+                std::string result;
 
-            if (value < 0) result = "-";
-            
-            // Integral part
-            size_t integral = (size_t)(std::abs(value));
-            result += (integral == 0) ? "0" : to_string(integral);
+                T integral_part;
+                T fractional_part = std::abs(std::modf(value, &integral_part));
+                integral_part = std::abs(integral_part);
+
+                // Integral part
+                if (value < 0) result = "-";
+
+                if (integral_part == 0) {
+                    result = "0";
+                }
+                else {
+                    for (short n_digits = log(integral_part) / log(10); n_digits + 1 > 0; n_digits --) {
+                        short digit = std::fmod(integral_part, pow10(n_digits + 1)) / pow10(n_digits);
+                        result += (char)('0' + digit);
+                    }
+                }
 
-            // Decimal part
-            size_t decimal = (size_t)(((double)std::abs(value) - (double)integral) * 100000);
+                // Decimal part
+                result += ".";
 
-            result += ".";
-            result += (decimal == 0) ? "0" : to_string(decimal);
+                if (fractional_part > 0) {
+                    fractional_part *= pow10(DECIMAL_PLACES);
+                    for (short n_digits = DECIMAL_PLACES; n_digits > 0; n_digits--) {
+                        short digit = std::fmod(fractional_part, pow10(n_digits)) / pow10(n_digits - 1);
+                        result += (char)('0' + digit);
+                    }
+                }
+                else {
+                    result += "0";
+                }
 
-            return result;
+                return result;
         }
     }
 
+    /** Sets how many places after the decimal will be written for floating point numbers
+     *
+     *  @param  precision   Number of decimal places
+     */
+    inline static void set_decimal_places(int precision) {
+        internals::DECIMAL_PLACES = precision;
+    }
+
     /** @name CSV Writing */
     ///@{
     /** 
@@ -102,6 +131,7 @@ namespace csv {
          *  @param  _out           Stream to write to
          *  @param  _quote_minimal Limit field quoting to only when necessary
         */
+
         DelimWriter(OutputStream& _out, bool _quote_minimal = true)
             : out(_out), quote_minimal(_quote_minimal) {};
 
@@ -213,7 +243,7 @@ namespace csv {
             bool quote_escape = false;
 
             for (auto ch : in) {
-                if (ch == Quote || ch == Delim) {
+                if (ch == Quote || ch == Delim || ch == '\r' || ch == '\n') {
                     quote_escape = true;
                     break;
                 }
@@ -222,9 +252,10 @@ namespace csv {
             if (!quote_escape) {
                 if (quote_minimal) return std::string(in);
                 else {
-                    std::string ret(Quote, 1);
+                    std::string ret(1, Quote);
                     ret += in.data();
                     ret += Quote;
+                    return ret;
                 }
             }