HISTORY.md - external/github.com/kjd/idna - Git at Google

 # History

 ## Unreleased

 - Added machine-readable attributes to exceptions, allowing UIs
   to provide more tailored errors.

 ## 3.18 (2026-06-02)

 - When decoding a domain, add a `display` argument that will pass
   through invalid labels rather than raising an exception.

 ## 3.17 (2026-05-28)

 - Substantial 75% reduction in memory usage through new data
   structures and some optimization in processing speed.
 - Added a general 1024-character input length cap to the public
   validation, conversion, and codec entry points. This is well above
   any legitimate domain or label and guards against pathological
   inputs.

 ## 3.16 (2026-05-22)

 - Add a command-line interface (`python -m idna`, also available as
   the `idna` script). Encodes or decodes one or more domains supplied
   as arguments or on standard input, with options to select A-label
   or U-label output and control error handling.
 - Raise the minimum supported Python version to 3.9
 - Various code quality improvements

 ## 3.15 (2026-05-12)

 - Enforce DNS-length cap on individual labels early in `check_label`,
   short-circuiting contextual-rule processing for oversized input
   while staying compatible with UTS 46 usage.
 - Tidy core helpers: hoist bidi category sets to module-level
   frozensets (avoiding per-codepoint list construction), simplify
   length checks, and reuse the shared `_unicode_dots_re` from
   `idna.core` in the codec module.
 - Use `raise ... from err` for proper exception chaining and
   switch internal string formatting to f-strings.
 - Allow `flit_core` 4.x in the build backend.
 - Expand the ruff lint set (flake8-bugbear, flake8-simplify,
   pyupgrade, perflint) and apply the surfaced fixes; pin lint CI
   to Python 3.14.
 - Add Dependabot configuration for GitHub Actions.
 - Convert README and HISTORY from reStructuredText to Markdown.
 - Reference CVE-2026-45409 for the 3.14 advisory in place of the
   initial GHSA identifier.

 Thanks to Felix Yan, Stan Ulbrych, and metsw24-max for
 contributions to this release.

 ## 3.14 (2026-05-10)

 - Removed opportunity to process long inputs into quadratic
   time by rejecting oversize inputs up-front. Closes a bypass
   of the CVE-2024-3651 mitigation. [CVE-2026-45409]

 Thanks to Stan Ulbrych for reporting the issue.

 ## 3.13 (2026-04-22)

 - Correct classification error for codepoint U+A7F1

 ## 3.12 (2026-04-21)

 - Update to Unicode 17.0.0.
 - Issue a deprecation warning for the transitional argument.
 - Added lazy-loading to provide some performance improvements.
 - Removed vestiges of code related to Python 2 support, including
   segmentation of data structures specific to Jython.

 Thanks to Rodrigo Nogueira for contributions to this release.

 ## 3.11 (2025-10-12)

 - Update to Unicode 16.0.0, including significant changes to UTS46
   processing. As a result of Unicode ending support for it, transitional
   processing no longer has an effect and returns the same result.
 - Add support for Python 3.14, lowest supported version is Python 3.8.
 - Various updates to packaging, including PEP 740 support.

 ## 3.10 (2024-09-15)

 - Reverted to Unicode 15.1.0 data. Unicode 16 has some significant changes
   to UTS46 processing that will require more work to properly implement.

 ## 3.9 (2024-09-13)

 - Update to Unicode 16.0.0
 - Deprecate setup.cfg in favour of pyproject.toml
 - Use ruff for code formatting

 Thanks to Waket Zheng for contributions to this release.

 ## 3.8 (2024-08-23)

 - Fix regression where IDNAError exception was not being produced for
   certain inputs.
 - Add support for Python 3.13, drop support for Python 3.5 as it is no
   longer testable.
 - Documentation improvements
 - Updates to package testing using Github actions

 Thanks to Hugo van Kemenade for contributions to this release.

 ## 3.7 (2024-04-11)

 - Fix issue where specially crafted inputs to encode() could
   take exceptionally long amount of time to process. [CVE-2024-3651]

 Thanks to Guido Vranken for reporting the issue.

 ## 3.6 (2023-11-25)

 - Fix regression to include tests in source distribution.

 ## 3.5 (2023-11-24)

 - Update to Unicode 15.1.0
 - String codec name is now "idna2008" as overriding the system codec
   "idna" was not working.
 - Fix typing error for codec encoding
 - "setup.cfg" has been added for this release due to some downstream
   lack of adherence to PEP 517. Should be removed in a future release
   so please prepare accordingly.
 - Removed reliance on a symlink for the "idna-data" tool to comport
   with PEP 517 and the Python Packaging User Guide for sdist archives.
 - Added security reporting protocol for project

 Thanks Jon Ribbens, Diogo Teles Sant'Anna, Wu Tingfeng for contributions
 to this release.

 ## 3.4 (2022-09-14)

 - Update to Unicode 15.0.0
 - Migrate to pyproject.toml for build information (PEP 621)
 - Correct another instance where generic exception was raised instead of
   IDNAError for malformed input
 - Source distribution uses zeroized file ownership for improved
   reproducibility

 Thanks to Seth Michael Larson for contributions to this release.

 ## 3.3 (2021-10-13)

 - Update to Unicode 14.0.0
 - Update to in-line type annotations
 - Throw IDNAError exception correctly for some malformed input
 - Advertise support for Python 3.10
 - Improve testing regime on Github
 - Fix Russian typo in documentation

 Thanks to Jon Defresne, Hugo van Kemenade, Seth Michael Larson,
 Patrick Ventuzelo and Boris Verhovsky for contributions to this
 release.

 ## 3.2 (2021-05-29)

 - Add type hints (Thanks, Seth Michael Larson!)
 - Remove support for Python 3.4

 ## 3.1 (2021-01-04)

 - Ensure license is included in package (Thanks, Julien Schueller)
 - No longer mark wheel has universal (Thanks, Matthieu Darbois)
 - Test on PowerPC using Travis CI

 ## 3.0 (2021-01-01)

 - Python 2 is no longer supported (the 2.x branch supports Python 2,
   use "idna<3" in your requirements file if you need Python 2 support)
 - Support for V2 UTS 46 test vectors.

 ## 2.10 (2020-06-27)

 - Update to Unicode 13.0.0.
 - Throws a more specific exception if "xn--" is provided as a label.
 - This is expected to be the last version that supports Python 2.

 ## 2.9 (2020-02-16)

 - Update to Unicode 12.1.0.
 - Prohibit A-labels ending with a hyphen (Thanks, Julien Bernard!)
 - Future-proofing: Test on Python 3.7 and 3.8, don't immediately
   fail should Python 4 come along.
 - Made BSD 3-clause license clearer

 ## 2.8 (2018-12-04)

 - Update to Unicode 11.0.0.
 - Provide more specific exceptions for some malformed labels.

 ## 2.7 (2018-06-10)

 - Update to Unicode 10.0.0.
 - No longer accepts dot-prefixed domains (e.g. ".example") as valid.
   This is to be more conformant with the UTS 46 spec. Users should
   strip dot prefixes from domains before processing.

 ## 2.6 (2017-08-08)

 - Allows generation of IDNA and UTS 46 table data for different
   versions of Unicode, by deriving properties directly from
   Unicode data.
 - Ability to generate RFC 5892/IANA-style table data
 - Diagnostic output of IDNA-related Unicode properties and
   derived calculations for a given codepoint
 - Support for idna.__version__ to report version
 - Support for idna.idnadata.__version__ and
   idna.uts46data.__version__ to report Unicode version of
   underlying IDNA and UTS 46 data respectively.

 ## 2.5 (2017-03-07)

 - Fix bug with Katakana middle dot context-rule (Thanks, Greg
   Shikhman.)

 ## 2.4 (2017-03-01)

 - Restore IDNAError to be a subclass of UnicodeError, as some users of
   this library are only looking for the latter to catch invalid strings.

 ## 2.3 (2017-02-28)

 - Fix bugs relating to deriving IDNAError from UnicodeError.
 - More memory footprint improvements (Thanks, Alex Gaynor)

 ## 2.2 (2016-12-21)

 - Made some changes to the UTS 46 data that should allow Jython to get around
   64kb Java class limits. (Thanks, John A. Booth and Marcin Płonka.)
 - In Python 2.6, skip two tests that rely on data not present in that
   Python version's unicodedata module.
 - Use relative imports to help downstream users.

 ## 2.1 (2016-03-20)

 - Memory consumption optimizations. The library should consume significantly
   less memory through smarter data structures being used to represent
   relevant Unicode properties. Many thanks to Shivaram Lingamneni for this
   patch.
 - Patches to make library work better with Python 2.6. The core library
   currently works however the unit testing does not. (Thanks, Robert
   Buchholz)
 - Better affix all Unicode codepoint properties to a specific version.

 ## 2.0 (2015-05-18)

 - Added support for Unicode IDNA Compatibility Processing (aka Unicode
   Technical Standard #46). Big thanks to Jon Ribbens who contributed this
   functionality.

 ## 1.1 (2015-01-27)

 - Use IDNA properties from Unicode 6.3.0. Internet Architecture Board (IAB)
   issued statement recommending against the use of Unicode 7.0.0 until
   issues relating to U+08A1 codepoint are resolved. See http://goo.gl/Ed1n0K
 - Identify some cases when label would be too longer to be a legal DNS name
   and raise an exception. (Thanks, Ed Lewis)

 ## 1.0 (2014-10-12)

 - Update IDNA properties for Unicode 7.0.0.

 ## 0.9 (2014-07-18)

 - Fix issue with non-UTF-8 environments reading the README file
   now that it contains non-ASCII. (Thanks, Tom Prince)
 - Codec functions are useful, so they are separated into their own
   module, rather than just existing for compatibility reasons.
 - Add LICENSE file.

 ## 0.8 (2014-07-09)

 - Added MANIFEST.in for correct source distribution compilation.

 ## 0.7 (2014-07-09)

 - Filled out missing tests for various functions.
 - Fix bug in CONTEXTO validation for Greek lower numeral sign (U+0375)
 - Fix bug in CONTEXTO validation for Japanese middle dot (U+30FB)
 - Improved documentation
 - Move designation to Stable

 ## 0.6 (2014-04-29)

 - Minor improvements to Python 3 support, tests (Thanks, Derek Wilson)

 ## 0.5 (2014-02-05)

 - Update IDNA properties for Unicode 6.3.0.

 ## 0.4 (2014-01-07)

 - Fix trove classifier for Python 3. (Thanks, Hynek Schlawack)

 ## 0.3 (2013-07-18)

 - Ported to Python 3.

 ## 0.2 (2013-07-16)

 - Improve packaging.
 - More conformant, passes all relevant tests in the Unicode TR46 test suite.

 ## 0.1 (2013-05-27)

 - First proof-of-concept version.
	# History

	## Unreleased

	- Added machine-readable attributes to exceptions, allowing UIs
	to provide more tailored errors.

	## 3.18 (2026-06-02)

	- When decoding a domain, add a `display` argument that will pass
	through invalid labels rather than raising an exception.

	## 3.17 (2026-05-28)

	- Substantial 75% reduction in memory usage through new data
	structures and some optimization in processing speed.
	- Added a general 1024-character input length cap to the public
	validation, conversion, and codec entry points. This is well above
	any legitimate domain or label and guards against pathological
	inputs.

	## 3.16 (2026-05-22)

	- Add a command-line interface (`python -m idna`, also available as
	the `idna` script). Encodes or decodes one or more domains supplied
	as arguments or on standard input, with options to select A-label
	or U-label output and control error handling.
	- Raise the minimum supported Python version to 3.9
	- Various code quality improvements

	## 3.15 (2026-05-12)

	- Enforce DNS-length cap on individual labels early in `check_label`,
	short-circuiting contextual-rule processing for oversized input
	while staying compatible with UTS 46 usage.
	- Tidy core helpers: hoist bidi category sets to module-level
	frozensets (avoiding per-codepoint list construction), simplify
	length checks, and reuse the shared `_unicode_dots_re` from
	`idna.core` in the codec module.
	- Use `raise ... from err` for proper exception chaining and
	switch internal string formatting to f-strings.
	- Allow `flit_core` 4.x in the build backend.
	- Expand the ruff lint set (flake8-bugbear, flake8-simplify,
	pyupgrade, perflint) and apply the surfaced fixes; pin lint CI
	to Python 3.14.
	- Add Dependabot configuration for GitHub Actions.
	- Convert README and HISTORY from reStructuredText to Markdown.
	- Reference CVE-2026-45409 for the 3.14 advisory in place of the
	initial GHSA identifier.

	Thanks to Felix Yan, Stan Ulbrych, and metsw24-max for
	contributions to this release.

	## 3.14 (2026-05-10)

	- Removed opportunity to process long inputs into quadratic
	time by rejecting oversize inputs up-front. Closes a bypass
	of the CVE-2024-3651 mitigation. [CVE-2026-45409]

	Thanks to Stan Ulbrych for reporting the issue.

	## 3.13 (2026-04-22)

	- Correct classification error for codepoint U+A7F1

	## 3.12 (2026-04-21)

	- Update to Unicode 17.0.0.
	- Issue a deprecation warning for the transitional argument.
	- Added lazy-loading to provide some performance improvements.
	- Removed vestiges of code related to Python 2 support, including
	segmentation of data structures specific to Jython.

	Thanks to Rodrigo Nogueira for contributions to this release.

	## 3.11 (2025-10-12)

	- Update to Unicode 16.0.0, including significant changes to UTS46
	processing. As a result of Unicode ending support for it, transitional
	processing no longer has an effect and returns the same result.
	- Add support for Python 3.14, lowest supported version is Python 3.8.
	- Various updates to packaging, including PEP 740 support.

	## 3.10 (2024-09-15)

	- Reverted to Unicode 15.1.0 data. Unicode 16 has some significant changes
	to UTS46 processing that will require more work to properly implement.

	## 3.9 (2024-09-13)

	- Update to Unicode 16.0.0
	- Deprecate setup.cfg in favour of pyproject.toml
	- Use ruff for code formatting

	Thanks to Waket Zheng for contributions to this release.

	## 3.8 (2024-08-23)

	- Fix regression where IDNAError exception was not being produced for
	certain inputs.
	- Add support for Python 3.13, drop support for Python 3.5 as it is no
	longer testable.
	- Documentation improvements
	- Updates to package testing using Github actions

	Thanks to Hugo van Kemenade for contributions to this release.

	## 3.7 (2024-04-11)

	- Fix issue where specially crafted inputs to encode() could
	take exceptionally long amount of time to process. [CVE-2024-3651]

	Thanks to Guido Vranken for reporting the issue.

	## 3.6 (2023-11-25)

	- Fix regression to include tests in source distribution.

	## 3.5 (2023-11-24)

	- Update to Unicode 15.1.0
	- String codec name is now "idna2008" as overriding the system codec
	"idna" was not working.
	- Fix typing error for codec encoding
	- "setup.cfg" has been added for this release due to some downstream
	lack of adherence to PEP 517. Should be removed in a future release
	so please prepare accordingly.
	- Removed reliance on a symlink for the "idna-data" tool to comport
	with PEP 517 and the Python Packaging User Guide for sdist archives.
	- Added security reporting protocol for project

	Thanks Jon Ribbens, Diogo Teles Sant'Anna, Wu Tingfeng for contributions
	to this release.

	## 3.4 (2022-09-14)

	- Update to Unicode 15.0.0
	- Migrate to pyproject.toml for build information (PEP 621)
	- Correct another instance where generic exception was raised instead of
	IDNAError for malformed input
	- Source distribution uses zeroized file ownership for improved
	reproducibility

	Thanks to Seth Michael Larson for contributions to this release.

	## 3.3 (2021-10-13)

	- Update to Unicode 14.0.0
	- Update to in-line type annotations
	- Throw IDNAError exception correctly for some malformed input
	- Advertise support for Python 3.10
	- Improve testing regime on Github
	- Fix Russian typo in documentation

	Thanks to Jon Defresne, Hugo van Kemenade, Seth Michael Larson,
	Patrick Ventuzelo and Boris Verhovsky for contributions to this
	release.

	## 3.2 (2021-05-29)

	- Add type hints (Thanks, Seth Michael Larson!)
	- Remove support for Python 3.4

	## 3.1 (2021-01-04)

	- Ensure license is included in package (Thanks, Julien Schueller)
	- No longer mark wheel has universal (Thanks, Matthieu Darbois)
	- Test on PowerPC using Travis CI

	## 3.0 (2021-01-01)

	- Python 2 is no longer supported (the 2.x branch supports Python 2,
	use "idna<3" in your requirements file if you need Python 2 support)
	- Support for V2 UTS 46 test vectors.

	## 2.10 (2020-06-27)

	- Update to Unicode 13.0.0.
	- Throws a more specific exception if "xn--" is provided as a label.
	- This is expected to be the last version that supports Python 2.

	## 2.9 (2020-02-16)

	- Update to Unicode 12.1.0.
	- Prohibit A-labels ending with a hyphen (Thanks, Julien Bernard!)
	- Future-proofing: Test on Python 3.7 and 3.8, don't immediately
	fail should Python 4 come along.
	- Made BSD 3-clause license clearer

	## 2.8 (2018-12-04)

	- Update to Unicode 11.0.0.
	- Provide more specific exceptions for some malformed labels.

	## 2.7 (2018-06-10)

	- Update to Unicode 10.0.0.
	- No longer accepts dot-prefixed domains (e.g. ".example") as valid.
	This is to be more conformant with the UTS 46 spec. Users should
	strip dot prefixes from domains before processing.

	## 2.6 (2017-08-08)

	- Allows generation of IDNA and UTS 46 table data for different
	versions of Unicode, by deriving properties directly from
	Unicode data.
	- Ability to generate RFC 5892/IANA-style table data
	- Diagnostic output of IDNA-related Unicode properties and
	derived calculations for a given codepoint
	- Support for idna.__version__ to report version
	- Support for idna.idnadata.__version__ and
	idna.uts46data.__version__ to report Unicode version of
	underlying IDNA and UTS 46 data respectively.

	## 2.5 (2017-03-07)

	- Fix bug with Katakana middle dot context-rule (Thanks, Greg
	Shikhman.)

	## 2.4 (2017-03-01)

	- Restore IDNAError to be a subclass of UnicodeError, as some users of
	this library are only looking for the latter to catch invalid strings.

	## 2.3 (2017-02-28)

	- Fix bugs relating to deriving IDNAError from UnicodeError.
	- More memory footprint improvements (Thanks, Alex Gaynor)

	## 2.2 (2016-12-21)

	- Made some changes to the UTS 46 data that should allow Jython to get around
	64kb Java class limits. (Thanks, John A. Booth and Marcin Płonka.)
	- In Python 2.6, skip two tests that rely on data not present in that
	Python version's unicodedata module.
	- Use relative imports to help downstream users.

	## 2.1 (2016-03-20)

	- Memory consumption optimizations. The library should consume significantly
	less memory through smarter data structures being used to represent
	relevant Unicode properties. Many thanks to Shivaram Lingamneni for this
	patch.
	- Patches to make library work better with Python 2.6. The core library
	currently works however the unit testing does not. (Thanks, Robert
	Buchholz)
	- Better affix all Unicode codepoint properties to a specific version.

	## 2.0 (2015-05-18)

	- Added support for Unicode IDNA Compatibility Processing (aka Unicode
	Technical Standard #46). Big thanks to Jon Ribbens who contributed this
	functionality.

	## 1.1 (2015-01-27)

	- Use IDNA properties from Unicode 6.3.0. Internet Architecture Board (IAB)
	issued statement recommending against the use of Unicode 7.0.0 until
	issues relating to U+08A1 codepoint are resolved. See http://goo.gl/Ed1n0K
	- Identify some cases when label would be too longer to be a legal DNS name
	and raise an exception. (Thanks, Ed Lewis)

	## 1.0 (2014-10-12)

	- Update IDNA properties for Unicode 7.0.0.

	## 0.9 (2014-07-18)

	- Fix issue with non-UTF-8 environments reading the README file
	now that it contains non-ASCII. (Thanks, Tom Prince)
	- Codec functions are useful, so they are separated into their own
	module, rather than just existing for compatibility reasons.
	- Add LICENSE file.

	## 0.8 (2014-07-09)

	- Added MANIFEST.in for correct source distribution compilation.

	## 0.7 (2014-07-09)

	- Filled out missing tests for various functions.
	- Fix bug in CONTEXTO validation for Greek lower numeral sign (U+0375)
	- Fix bug in CONTEXTO validation for Japanese middle dot (U+30FB)
	- Improved documentation
	- Move designation to Stable

	## 0.6 (2014-04-29)

	- Minor improvements to Python 3 support, tests (Thanks, Derek Wilson)

	## 0.5 (2014-02-05)

	- Update IDNA properties for Unicode 6.3.0.

	## 0.4 (2014-01-07)

	- Fix trove classifier for Python 3. (Thanks, Hynek Schlawack)

	## 0.3 (2013-07-18)

	- Ported to Python 3.

	## 0.2 (2013-07-16)

	- Improve packaging.
	- More conformant, passes all relevant tests in the Unicode TR46 test suite.

	## 0.1 (2013-05-27)

	- First proof-of-concept version.