| // Copyright (c) 2019, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| /// Locale extensions as defined for [Unicode Locale |
| /// Identifiers](http://www.unicode.org/reports/tr35/#Unicode_locale_identifier). |
| /// |
| /// These extensions cover Locale information that aren't captured by the |
| /// language, script, region and variants subtags of the Unicode Language |
| /// Identifier. Please see the Unicode Technical Standard linked above. |
| class LocaleExtensions { |
| /// Constructor. |
| /// |
| /// Keys in each of the maps passed to this contructor must be syntactically |
| /// valid extension keys, and must already be normalized (correct case). |
| LocaleExtensions( |
| Map<String, String> uExtensions, |
| Map<String, String> tExtensions, |
| Map<String, String> otherExtensions, |
| this._xExtensions) |
| : _uExtensions = _sortedUnmodifiable(uExtensions), |
| _tExtensions = _sortedUnmodifiable(tExtensions), |
| _otherExtensions = _sortedUnmodifiable(otherExtensions) { |
| // Debug-mode asserts to ensure all parameters are normalized and UTS #35 |
| // compliant. |
| assert( |
| uExtensions == null || |
| uExtensions.entries.every((e) { |
| if (!_uExtensionsValidKeysRE.hasMatch(e.key)) return false; |
| // TODO(hugovdm) reconsider this representation: "true" values are |
| // suppressed in canonical Unicode BCP47 Locale Identifiers, but |
| // we may choose to represent them as "true" in memory. |
| if (e.value == '' && e.key != '') return true; |
| if (!_uExtensionsValidValuesRE.hasMatch(e.value)) return false; |
| return true; |
| }), |
| 'uExtensions keys must match ' |
| 'RegExp/${_uExtensionsValidKeysRE.pattern}/. ' |
| 'uExtensions values must match ' |
| 'RegExp/${_uExtensionsValidValuesRE.pattern}/. ' |
| 'uExtensions.entries: ${uExtensions.entries}.'); |
| assert( |
| tExtensions == null || |
| tExtensions.entries.every((e) { |
| if (!_tExtensionsValidKeysRE.hasMatch(e.key)) return false; |
| if (e.key == '') { |
| if (!_validTlangRE.hasMatch(e.value)) return false; |
| } else { |
| if (!_tExtensionsValidValuesRE.hasMatch(e.value)) return false; |
| } |
| return true; |
| }), |
| 'tExtensions keys must match ' |
| 'RegExp/${_tExtensionsValidKeysRE.pattern}/. ' |
| 'tExtensions values other than tlang must match ' |
| 'RegExp/${_tExtensionsValidValuesRE.pattern}/. ' |
| 'Entries: ${tExtensions.entries}.'); |
| assert( |
| otherExtensions == null || |
| otherExtensions.entries.every((e) { |
| if (!_otherExtensionsValidKeysRE.hasMatch(e.key)) return false; |
| if (!_otherExtensionsValidValuesRE.hasMatch(e.value)) { |
| return false; |
| } |
| return true; |
| }), |
| 'otherExtensions keys must match ' |
| 'RegExp/${_otherExtensionsValidKeysRE.pattern}. ' |
| 'otherExtensions values must match ' |
| 'RegExp/${_otherExtensionsValidValuesRE.pattern}. ' |
| 'Entries: ${otherExtensions.entries}.'); |
| assert( |
| _xExtensions == null || _validXExtensionsRE.hasMatch(_xExtensions), |
| '_xExtensions must match RegExp/${_validXExtensionsRE.pattern}/ ' |
| 'but is "$_xExtensions".'); |
| } |
| |
| /// For debug/assert-use only! Matches keys considered valid for |
| /// [_uExtensions], does not imply keys are valid as per Unicode LDML spec! |
| // |
| // Must be static to get tree-shaken away in production code. |
| static final _uExtensionsValidKeysRE = RegExp(r'^$|^[a-z\d][a-z]$'); |
| |
| /// For debug/assert-use only! Matches values considered valid for |
| /// [_uExtensions], does not imply values are valid as per Unicode LDML spec! |
| // |
| // Must be static to get tree-shaken away in production code. |
| static final _uExtensionsValidValuesRE = |
| RegExp(r'^[a-z\d]{3,8}([-][a-z\d]{3,8})*$'); |
| |
| /// For debug/assert-use only! Matches keys considered valid for |
| /// [_tExtensions], does not imply keys are valid as per Unicode LDML spec! |
| // |
| // Must be static to get tree-shaken away in production code. |
| static final _tExtensionsValidKeysRE = RegExp(r'^$|^[a-z]\d$'); |
| |
| /// For debug/assert-use only! With the exception of `tlang`, matches values |
| /// considered valid for [_tExtensions], does not imply values are valid as |
| /// per Unicode LDML spec! |
| // |
| // Must be static to get tree-shaken away in production code. |
| static final _tExtensionsValidValuesRE = |
| RegExp(r'^[a-z\d]{3,8}([-][a-z\d]{3,8})*$'); |
| |
| /// For debug/assert-use only! Matches keys considered valid for |
| /// [_otherExtensions], does not imply keys are valid as per Unicode LDML |
| /// spec! |
| // |
| // Must be static to get tree-shaken away in production code. |
| static final _otherExtensionsValidKeysRE = RegExp(r'^[a-svwyz]$'); |
| |
| /// For debug/assert-use only! Matches values considered valid for |
| /// [_otherExtensions], does not imply values are valid as per Unicode LDML |
| /// spec! |
| // |
| // Must be static to get tree-shaken away in production code. |
| static final _otherExtensionsValidValuesRE = |
| RegExp(r'^[a-z\d]{2,8}([-][a-z\d]{2,8})*$'); |
| |
| /// For debug/assert-use only! Matches values valid for [_xExtensions]. |
| // |
| // Must be static to get tree-shaken away in production code. |
| static final _validXExtensionsRE = |
| RegExp(r'^[a-z\d]{1,8}([-][a-z\d]{1,8})*$'); |
| |
| /// For debug/assert-use only! Matches values valid for tlang. |
| // |
| // Must be static to get tree-shaken away in production code. |
| static final _validTlangRE = RegExp( |
| // Full string match start |
| r'^' |
| |
| // Language is required in a tlang identifier. |
| r'([a-z]{2,3}|[a-z]{5,8})' // Language |
| |
| // Optional script |
| r'(-[a-z]{4})?' |
| |
| // Optional region |
| r'(-[a-z]{2}|-\d{3})?' |
| |
| // Any number of variant subtags |
| r'(-([a-z\d]{5,8}|\d[a-z\d]{3}))*' |
| |
| // Full string match end |
| r'$'); |
| |
| /// `-u-` extension, with keys in sorted order. Attributes are stored under |
| /// the zero-length string as key. Keywords (consisting of `key` and `type`) |
| /// are stored under normalized (lowercased) `key`. See |
| /// http://www.unicode.org/reports/tr35/#unicode_locale_extensions for |
| /// details. |
| final Map<String, String> _uExtensions; |
| |
| /// `-t-` extension, with keys in sorted order. tlang attributes are stored |
| /// under the zero-length string as key. See |
| /// http://www.unicode.org/reports/tr35/#transformed_extensions for |
| /// details. |
| final Map<String, String> _tExtensions; |
| |
| /// Other extensions, with keys in sorted order. See |
| /// http://www.unicode.org/reports/tr35/#other_extensions for details. |
| final Map<String, String> _otherExtensions; |
| |
| /// -x- extension values. See |
| /// http://www.unicode.org/reports/tr35/#pu_extensions for details. |
| final String _xExtensions; |
| |
| /// List of subtags in the [Unicode Locale |
| /// Identifier](https://www.unicode.org/reports/tr35/#Unicode_locale_identifier) |
| /// extensions, including private use extensions. |
| /// |
| /// This covers everything after the unicode_language_id. If there are no |
| /// extensions (i.e. the Locale Identifier has only language, script, region |
| /// and/or variants), this will be an empty list. |
| /// |
| /// These subtags are sorted and normalized, ready for joining with a |
| /// unicode_language_id and '-' as delimiter to provide a UTS #35 compliant |
| /// normalized Locale Identifier. |
| List<String> get subtags { |
| final result = <String>[]; |
| final resultVWYZ = <String>[]; |
| |
| _otherExtensions.forEach((singleton, value) { |
| final letter = (singleton.codeUnitAt(0) - 0x61) & 0xFFFF; |
| // 't', 'u' and 'x' are handled by other members. |
| assert(letter < 26 && letter != 19 && letter != 20 && letter != 23); |
| if (letter < 19) { |
| result.addAll([singleton, value]); |
| } else { |
| resultVWYZ.addAll([singleton, value]); |
| } |
| }); |
| if (_tExtensions.isNotEmpty) { |
| result.add('t'); |
| _tExtensions.forEach((key, value) { |
| if (key != '') result.add(key); |
| result.add(value); |
| }); |
| } |
| if (_uExtensions.isNotEmpty) { |
| result.add('u'); |
| _uExtensions.forEach((key, value) { |
| if (key != '') result.add(key); |
| if (value != '') result.add(value); |
| }); |
| } |
| |
| if (resultVWYZ.isNotEmpty) { |
| result.addAll(resultVWYZ); |
| } |
| if (_xExtensions != null) { |
| result.add('x-$_xExtensions'); |
| } |
| return result; |
| } |
| } |
| |
| /// Creates an unmodifiable and sorted version of `unsorted`. |
| Map<String, String> _sortedUnmodifiable(Map<String, String> unsorted) { |
| if (unsorted == null) { |
| return const {}; |
| } |
| var map = <String, String>{}; |
| for (var key in unsorted.keys.toList()..sort()) { |
| map[key] = unsorted[key]; |
| } |
| return Map.unmodifiable(map); |
| } |
