News

3.3.5 - 2025-06-01

Improvements

* docs: Fixed {StringScanner} document URL.
* GH-343
* Patch by Petrik de Heus

Thanks

*  Petrik de Heus

3.3.4 - 2025-04-13

Improvements

* `csv-filter`: Removed an experimental command line tool.
* GH-341

3.3.3 - 2025-03-20

Improvements

* `csv-filter`: Added an experimental command line tool to filter a CSV.
* Patch by Burdette Lamar

Fixes

* Fixed wrong EOF detection for {ARGF}
* GH-328
* Reported by Takeshi Nishimatsu

* Fixed a regression bug that {CSV.open} rejects integer mode.
* GH-336
* Reported by Dave Burgess

Thanks

* Takeshi Nishimatsu

* Burdette Lamar

* Dave Burgess

3.3.2 - 2024-12-21

Fixes

* Fixed a parse bug with a quoted line with `col_sep` and an empty
line. This was introduced in 3.3.
* GH-324
* Reported by stoodfarback

Thanks

* stoodfarback

3.3.1 - 2024-12-15

Improvements

* {CSV.open}: Changed to detect BOM by default. Note that this isn't
enabled on Windows because Ruby may have a bug. See also:
https://bugs.ruby-lang.org/issues/20526
* GH-301
* Reported by Junichi Ito

* Improved performance.
* GH-311
* GH-312
* Patch by Vladimir Kochnev

* {CSV.open}: Added support for {StringIO} as an input.
* GH-300
* GH-302
* Patch by Marcelo

* Added a built-in time converter. You can use it by `converters:
:time`.
* GH-313
* Patch by Bart de Water

* Added {CSV::TSV} for tab-separated values.
* GH-272
* GH-319
* Reported by kojix2
* Patch by Jas

Thanks

* Junichi Ito

* Vladimir Kochnev

* Marcelo

* Bart de Water

* kojix2

* Jas

3.3.0 - 2024-03-22

Fixes

* Fixed a regression parse bug in 3.2 that parsing with
`:skip_lines` may cause wrong result.

3.2.9 - 2024-03-22

Fixes

* Fixed a parse bug that wrong result may be happen when:

* `:skip_lines` is used
* `:row_separator` is `"\r\n"`
* There is a line that includes `\n` as a column value

Reported by Ryo Tsukamoto.

GH-296

Thanks

* Ryo Tsukamoto

3.2.8 - 2023-11-08

Improvements

* Added {CSV::InvalidEncodingError}.

Patch by Kosuke Shibata.

GH-287

Thanks

* Kosuke Shibata

3.2.7 - 2023-06-26

Improvements

* Removed an unused internal variable.
[GH-273](https://github.com/ruby/csv/issues/273)
[Patch by Mau Magnaguagno]

* Changed to use `https://` instead of `http://` in documents.
[GH-274](https://github.com/ruby/csv/issues/274)
[Patch by Vivek Bharath Akupatni]

* Added prefix to a helper module in test.
[GH-278](https://github.com/ruby/csv/issues/278)
[Patch by Luke Gruber]

* Added a documentation for `liberal_parsing: {backslash_quotes: true}`.
[GH-280](https://github.com/ruby/csv/issues/280)
[Patch by Mark Schneider]

Fixes

* Fixed a wrong execution result in documents.
[GH-276](https://github.com/ruby/csv/issues/276)
[Patch by Yuki Tsujimoto]

* Fixed a bug that the same line is used multiple times.
[GH-279](https://github.com/ruby/csv/issues/279)
[Reported by Gabriel Nagy]

Thanks

* Mau Magnaguagno

* Vivek Bharath Akupatni

* Yuki Tsujimoto

* Luke Gruber

* Mark Schneider

* Gabriel Nagy

3.2.6 - 2022-12-08

Improvements

* {CSV#read} consumes the same lines with other methods like
{CSV#shift}.
[[GitHub#258](https://github.com/ruby/csv/issues/258)]
[Reported by Lhoussaine Ghallou]

* All {Enumerable} based methods consume the same lines with other
methods. This may have a performance penalty.
[[GitHub#260](https://github.com/ruby/csv/issues/260)]
[Reported by Lhoussaine Ghallou]

* Simplify some implementations.
[[GitHub#262](https://github.com/ruby/csv/pull/262)]
[[GitHub#263](https://github.com/ruby/csv/pull/263)]
[Patch by Mau Magnaguagno]

Fixes

* Fixed {CSV.generate_lines} document.
[[GitHub#257](https://github.com/ruby/csv/pull/257)]
[Patch by Sampat Badhe]

Thanks

* Sampat Badhe

* Lhoussaine Ghallou

* Mau Magnaguagno

3.2.5 - 2022-08-26

Improvements

* Added {CSV.generate_lines}.
[[GitHub#255](https://github.com/ruby/csv/issues/255)]
[Reported by OKURA Masafumi]
[[GitHub#256](https://github.com/ruby/csv/pull/256)]
[Patch by Eriko Sugiyama]

Thanks

* OKURA Masafumi

* Eriko Sugiyama

3.2.4 - 2022-08-22

Improvements

* Cleaned up internal implementations.
[[GitHub#249](https://github.com/ruby/csv/pull/249)]
[[GitHub#250](https://github.com/ruby/csv/pull/250)]
[[GitHub#251](https://github.com/ruby/csv/pull/251)]
[Patch by Mau Magnaguagno]

* Added support for RFC 3339 style time.
[[GitHub#248](https://github.com/ruby/csv/pull/248)]
[Patch by Thierry Lambert]

* Added support for transcoding String CSV. Syntax is
`from-encoding:to-encoding`.
[[GitHub#254](https://github.com/ruby/csv/issues/254)]
[Reported by Richard Stueven]

* Added quoted information to {CSV::FieldInfo}.
[[GitHub#254](https://github.com/ruby/csv/pull/253)]
[Reported by Hirokazu SUZUKI]

Fixes

* Fixed a link in documents.
[[GitHub#244](https://github.com/ruby/csv/pull/244)]
[Patch by Peter Zhu]

Thanks

* Peter Zhu

* Mau Magnaguagno

* Thierry Lambert

* Richard Stueven

* Hirokazu SUZUKI

3.2.3 - 2022-04-09

Improvements

* Added contents summary to {CSV::Table#inspect}.
[GitHub#229][Patch by Eriko Sugiyama]
[GitHub#235][Patch by Sampat Badhe]

* Suppressed `$INPUT_RECORD_SEPARATOR` deprecation warning by
{Warning.warn}.
[GitHub#233][Reported by Jean byroot Boussier]

* Improved error message for liberal parsing with quoted values.
[GitHub#231][Patch by Nikolay Rys]

* Fixed typos in documentation.
[GitHub#236][Patch by Sampat Badhe]

* Added `:max_field_size` option and deprecated `:field_size_limit` option.
[GitHub#238][Reported by Dan Buettner]

* Added `:symbol_raw` to built-in header converters.
[GitHub#237][Reported by taki]
[GitHub#239][Patch by Eriko Sugiyama]

Fixes

* Fixed a bug that some texts may be dropped unexpectedly.
[Bug #18245][ruby-core:105587][Reported by Hassan Abdul Rehman]

* Fixed a bug that `:field_size_limit` doesn't work with not complex row.
[GitHub#238][Reported by Dan Buettner]

Thanks

* Hassan Abdul Rehman

* Eriko Sugiyama

* Jean byroot Boussier

* Nikolay Rys

* Sampat Badhe

* Dan Buettner

* taki

3.2.2 - 2021-12-24

Improvements

* Added a validation for invalid option combination.
[GitHub#225][Patch by adamroyjones]

* Improved documentation for developers.
[GitHub#227][Patch by Eriko Sugiyama]

Fixes

* Fixed a bug that all of {ARGF} contents may not be consumed.
[GitHub#228][Reported by Rafael Navaza]

Thanks

* adamroyjones

* Eriko Sugiyama

* Rafael Navaza

3.2.1 - 2021-10-23

Improvements

* doc: Fixed wrong class name.
[GitHub#217][Patch by Vince]

* Changed to always use `"\n"` for the default row separator on Ruby
3.0 or later because `$INPUT_RECORD_SEPARATOR` was deprecated
since Ruby 3.0.

* Added support for Ractor.
[GitHub#218][Patch by rm155]

* Users who want to use the built-in converters in non-main
  Ractors need to call {Ractor.make_shareable(CSV::Converters)}
  and/or {Ractor.make_shareable(CSV::HeaderConverters)} before
  creating non-main Ractors.

Thanks

* Vince

* Joakim Antman

* rm155

3.2.0 - 2021-06-06

Improvements

* {CSV.open}: Added support for `:newline` option.
[GitHub#198][Patch by Nobuyoshi Nakada]

* {CSV::Table#each}: Added support for column mode with duplicated
headers.
[GitHub#206][Reported by Yaroslav Berezovskiy]

* {Object#CSV}: Added support for Ruby 3.0.

* {CSV::Row}: Added support for pattern matching.
[GitHub#207][Patch by Kevin Newton]

Fixes

* Fixed typos in documentation.
[GitHub#196][GitHub#205][Patch by Sampat Badhe]

Thanks

* Sampat Badhe

* Nobuyoshi Nakada

* Yaroslav Berezovskiy

* Kevin Newton

3.1.9 - 2020-11-23

Fixes

* Fixed a compatibility bug that the line to be processed by
`skip_lines:` has a row separator.
[GitHub#194][Reported by Josef Šimánek]

Thanks

* Josef Šimánek

3.1.8 - 2020-11-18

Improvements

* Improved documentation.
[Patch by Burdette Lamar]

Thanks

* Burdette Lamar

3.1.7 - 2020-08-04

Improvements

* Improved document.
[GitHub#158][GitHub#160][GitHub#161]
[Patch by Burdette Lamar]

* Updated required Ruby version to 2.5 or later.
[GitHub#159]
[Patch by Gabriel Nagy]

* Removed stringio 0.1 or later dependency.

Thanks

* Burdette Lamar

* Gabriel Nagy

3.1.6 - 2020-07-20

Improvements

* Improved document.
[GitHub#127][GitHub#135][GitHub#136][GitHub#137][GitHub#139][GitHub#140]
[GitHub#141][GitHub#142][GitHub#143][GitHub#145][GitHub#146][GitHub#148]
[GitHub#148][GitHub#151][GitHub#152][GitHub#154][GitHub#155][GitHub#157]
[Patch by Burdette Lamar]

* {CSV.open}: Added support for `undef: :replace`.
[GitHub#129][Patch by Koichi ITO]

* {CSV.open}: Added support for `invalid: :replace`.
[GitHub#129][Patch by Koichi ITO]

* Don't run quotable check for invalid encoding field values.
[GitHub#131][Patch by Koichi ITO]

* Added support for specifying the target indexes and names to
`force_quotes:`.
[GitHub#153][Reported by Aleksandr]

* {CSV.generate}: Changed to use the encoding of the first non-ASCII
field rather than the encoding of ASCII only field.

* Changed to require the stringio gem 0.1.3 or later.

Thanks

* Burdette Lamar

* Koichi ITO

* Aleksandr

3.1.5 - 2020-05-18

Improvements

* Improved document.
[GitHub#124][Patch by Burdette Lamar]

Fixes

* Added missing document files.
[GitHub#125][Reported by joast]

Thanks

* Burdette Lamar

* joast

3.1.4 - 2020-05-17

Improvements

* Improved document.
[GitHub#122][Patch by Burdette Lamar]

* Stopped to dropping stack trace for exception caused by
{CSV.parse_line}.
[GitHub#120][Reported by Kyle d'Oliveira]

Fixes

* Fixed a bug that `:write_nil_value` or `:write_empty_value` don't
work with non {String} objects.
[GitHub#123][Reported by asm256]

Thanks

* Burdette Lamar

* asm256

* Kyle d'Oliveira

3.1.3 - 2020-05-09

Improvements

* {CSV::Row#dup}: Copied deeply.
[GitHub#108][Patch by Jim Kane]

Fixes

* Fixed a infinite loop bug for zero length match `skip_lines`.
[GitHub#110][Patch by Mike MacDonald]

* {CSV.generate}: Fixed a bug that encoding isn't set correctly.
[GitHub#110][Patch by Seiei Miyagi]

* Fixed document for the `:strip` option.
[GitHub#114][Patch by TOMITA Masahiro]

* Fixed a parse bug when split charcter exists in middle of column
value.
[GitHub#115][Reported by TOMITA Masahiro]

Thanks

* Jim Kane

* Mike MacDonald

* Seiei Miyagi

* TOMITA Masahiro

3.1.2 - 2019-10-12

Improvements

* Added `:col_sep` check.
[GitHub#94][Reported by Florent Beaurain]

* Suppressed warnings.
[GitHub#96][Patch by Nobuyoshi Nakada]

* Improved documentation.
[GitHub#101][GitHub#102][Patch by Vitor Oliveira]

Fixes

* Fixed a typo in documentation.
[GitHub#95][Patch by Yuji Yaginuma]

* Fixed a multibyte character handling bug.
[GitHub#97][Patch by koshigoe]

* Fixed typos in documentation.
[GitHub#100][Patch by Vitor Oliveira]

* Fixed a bug that seeked {StringIO} isn't accepted.
[GitHub#98][Patch by MATSUMOTO Katsuyoshi]

* Fixed a bug that {CSV.generate_line} doesn't work with
{Encoding.default_internal}.
[GitHub#105][Reported by David Rodríguez]

Thanks

* Florent Beaurain

* Yuji Yaginuma

* Nobuyoshi Nakada

* koshigoe

* Vitor Oliveira

* MATSUMOTO Katsuyoshi

* David Rodríguez

3.1.1 - 2019-04-26

Improvements

* Added documentation for `strip` option.
[GitHub#88][Patch by hayashiyoshino]

* Added documentation for `write_converters`, `write_nil_value` and
`write_empty_value` options.
[GitHub#87][Patch by Masafumi Koba]

* Added documentation for `quote_empty` option.
[GitHub#89][Patch by kawa\_tech]

Fixes

* Fixed a bug that `strip; true` removes a newline.

Thanks

* hayashiyoshino

* Masafumi Koba

* kawa\_tech

3.1.0 - 2019-04-17

Fixes

* Fixed a backward incompatibility bug that {CSV#eof?} may raises an
error.
[GitHub#86][Reported by krororo]

Thanks

* krororo

3.0.9 - 2019-04-15

Fixes

* Fixed a test for Windows.

3.0.8 - 2019-04-11

Fixes

* Fixed a bug that `strip: String` doesn't work.

3.0.7 - 2019-04-08

Improvements

* Improve parse performance 1.5x by introducing loose parser.

Fixes

* Fix performance regression in 3.0.

* Fix a bug that {CSV#line} returns wrong value when you
use `quote_char: nil`.

3.0.6 - 2019-03-30

Improvements

* {CSV.foreach}: Added support for `mode`.

3.0.5 - 2019-03-24

Improvements

* Added `:liberal_parsing => {backslash_quote: true}` option.
[GitHub#74][Patch by 284km]

* Added `:write_converters` option.
[GitHub#73][Patch by Danillo Souza]

* Added `:write_nil_value` option.

* Added `:write_empty_value` option.

* Improved invalid byte line number detection.
[GitHub#78][Patch by Alyssa Ross]

* Added `quote_char: nil` optimization.
[GitHub#79][Patch by 284km]

* Improved error message.
[GitHub#81][Patch by Andrés Torres]

* Improved IO-like implementation for {StringIO} data.
[GitHub#80][Patch by Genadi Samokovarov]

* Added `:strip` option.
[GitHub#58]

Fixes

* Fixed a compatibility bug that {CSV#each} doesn't care {CSV#shift}.
[GitHub#76][Patch by Alyssa Ross]

* Fixed a compatibility bug that {CSV#eof?} doesn't care {CSV#each}
and {CSV#shift}.
[GitHub#77][Reported by Chi Leung]

* Fixed a compatibility bug that invalid line isn't ignored.
[GitHub#82][Reported by krororo]

* Fixed a bug that `:skip_lines` doesn't work with multibyte characters data.
[GitHub#83][Reported by ff2248]

Thanks

* Alyssa Ross

* 284km

* Chi Leung

* Danillo Souza

* Andrés Torres

* Genadi Samokovarov

* krororo

* ff2248

3.0.4 - 2019-01-25

Improvements

* Removed duplicated {CSV::Row#include?} implementations.
[GitHub#69][Patch by Max Schwenk]

* Removed duplicated {CSV::Row#header?} implementations.
[GitHub#70][Patch by Max Schwenk]

Fixes

* Fixed a typo in document.
[GitHub#72][Patch by Artur Beljajev]

* Fixed a compatibility bug when row headers are changed.
[GitHub#71][Reported by tomoyuki kosaka]

Thanks

* Max Schwenk

* Artur Beljajev

* tomoyuki kosaka

3.0.3 - 2019-01-12

Improvements

* Migrated benchmark tool to benchmark-driver from benchmark-ips.
[GitHub#57][Patch by 284km]

* Added `liberal_parsing: {double_quote_outside_quote: true}` parse
option.
[GitHub#66][Reported by Watson]

* Added `quote_empty:` write option.
[GitHub#35][Reported by Dave Myron]

Fixes

* Fixed a compatibility bug that {CSV.generate} always return
{ASCII-8BIT} encoding string.
[GitHub#63][Patch by Watson]

* Fixed a compatibility bug that `CSV.parse("", headers: true)`
doesn't return {CSV::Table}.
[GitHub#64][Reported by Watson][Patch by 284km]

* Fixed a compatibility bug that multiple-characters column
separator doesn't work.
[GitHub#67][Reported by Jesse Reiss]

* Fixed a compatibility bug that double `#each` parse twice.
[GitHub#68][Reported by Max Schwenk]

Thanks

* Watson

* 284km

* Jesse Reiss

* Dave Myron

* Max Schwenk

3.0.2 - 2018-12-23

Improvements

* Changed to use strscan in parser.
[GitHub#52][Patch by 284km]

* Improves CSV write performance.
3.0 will be about 2 times faster than 3.0.

* Improves CSV parse performance for complex case.
3.0 will be about 2 times faster than 3.0.

Fixes

* Fixed a parse error bug for new line only input with `headers` option.
[GitHub#53][Reported by Chris Beer]

* Fixed some typos in document.
[GitHub#54][Patch by Victor Shepelev]

Thanks

* 284km

* Chris Beer

* Victor Shepelev

3.0.1 - 2018-12-07

Improvements

* Added a test.
[GitHub#38][Patch by 284km]

* {CSV::Row#dup}: Changed to duplicate internal data.
[GitHub#39][Reported by André Guimarães Sakata]

* Documented `:nil_value` and `:empty_value` options.
[GitHub#41][Patch by OwlWorks]

* Added support for separator detection for non-seekable inputs.
[GitHub#45][Patch by Ilmari Karonen]

* Removed needless code.
[GitHub#48][Patch by Espartaco Palma]

* Added support for parsing header only CSV with `headers: true`.
[GitHub#47][Patch by Kazuma Shibasaka]

* Added support for coverage report in CI.
[GitHub#48][Patch by Espartaco Palma]

* Improved auto CR row separator detection.
[GitHub#51][Reported by Yuki Kurihara]

Fixes

* Fixed a typo in document.
[GitHub#40][Patch by Marcus Stollsteimer]

Thanks

* 284km

* André Guimarães Sakata

* Marcus Stollsteimer

* OwlWorks

* Ilmari Karonen

* Espartaco Palma

* Kazuma Shibasaka

* Yuki Kurihara

3.0.0 - 2018-06-06

Fixes

* Fixed a bug that header isn't returned for empty row.
[GitHub#37][Patch by Grace Lee]

Thanks

* Grace Lee

1.0.2 - 2018-05-03

Improvements

* Split file for CSV::VERSION

* Code cleanup: Split csv.rb into a more manageable structure
[GitHub#19][Patch by Espartaco Palma]
[GitHub#20][Patch by Steven Daniels]

* Use CSV::MalformedCSVError for invalid encoding line
[GitHub#26][Reported by deepj]

* Support implicit Row <-> Array conversion
[Bug #10013][ruby-core:63582][Reported by Dawid Janczak]

* Update class docs
[GitHub#32][Patch by zverok]

* Add {Row#each_pair}
[GitHub#33][Patch by zverok]

* Improve CSV performance
[GitHub#30][Patch by Watson]

* Add :nil_value and :empty_value option

Fixes

* Fix a bug that "bom|utf-8" doesn't work
[GitHub#23][Reported by Pavel Lobashov]

* {CSV::Row#to_h}, `#to_hash`: uses the same value as {Row#[]}
[Bug #14482][Reported by tomoya ishida]

* Make row separator detection more robust
[GitHub#25][Reported by deepj]

* Fix a bug that too much separator when col_sep is `" "`
[Bug #8784][ruby-core:63582][Reported by Sylvain Laperche]

Thanks

* Espartaco Palma

* Steven Daniels

* deepj

* Dawid Janczak

* zverok

* Watson

* Pavel Lobashov

* tomoya ishida

* Sylvain Laperche

* Ryunosuke Sato

1.0.1 - 2018-02-09

Improvements

* {CSV::Table#delete}: Added bulk delete support. You can delete
multiple rows and columns at once.
[GitHub#4][Patch by Vladislav]

* Updated Gem description.
[GitHub#11][Patch by Marcus Stollsteimer]

* Code cleanup.
[GitHub#12][Patch by Marcus Stollsteimer]
[GitHub#14][Patch by Steven Daniels]
[GitHub#18][Patch by takkanm]

* {CSV::Table#dig}: Added.
[GitHub#15][Patch by Tomohiro Ogoke]

* {CSV::Row#dig}: Added.
[GitHub#15][Patch by Tomohiro Ogoke]

* Added ISO 8601 support to date time converter.
[GitHub#16]

Fixes

* Fixed wrong {CSV::VERSION}.
[GitHub#10][Reported by Marcus Stollsteimer]

* {CSV.generate}: Fixed a regression bug that {String} argument is
ignored.
[GitHub#13][Patch by pavel]

Thanks

* Vladislav

* Marcus Stollsteimer

* Steven Daniels

* takkanm

* Tomohiro Ogoke

* pavel