From 831b7862f29371ccab435ecef450d42fff7214ab Mon Sep 17 00:00:00 2001
From: Romain Menke <romainmenke@gmail.com>
Date: Thu, 17 Sep 2026 19:56:32 +0200
Subject: [PATCH 1/2] css-tokenizer: fix handling of astral code points

---
 package-lock.json                               | 8 ++++----
 packages/css-tokenizer/CHANGELOG.md             | 4 ++++
 packages/css-tokenizer/dist/index.mjs           | 2 +-
 packages/css-tokenizer/package.json             | 2 +-
 packages/css-tokenizer/src/consume/url-token.ts | 8 ++++----
 packages/css-tokenizer/src/reader.ts            | 2 +-
 6 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/package-lock.json b/package-lock.json
index 9f3b890e07..667f0c5545 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -2694,9 +2694,9 @@
 			"license": "MIT"
 		},
 		"node_modules/@rmenke/css-tokenizer-tests": {
-			"version": "1.2.0",
-			"resolved": "https://registry.npmjs.org/@rmenke/css-tokenizer-tests/-/css-tokenizer-tests-1.2.0.tgz",
-			"integrity": "sha512-XfdeXzW5QGc3inl69eid2FTLGY/514xs+VXQWlEzdUVm1QdU6MicU5S2hcEbHoC9WMzIMALTzxiZb49w+xJk0Q==",
+			"version": "1.3.1",
+			"resolved": "https://registry.npmjs.org/@rmenke/css-tokenizer-tests/-/css-tokenizer-tests-1.3.1.tgz",
+			"integrity": "sha512-iLcijthn5fFF4NBt2VhAaf2mv6RRoeQbHqsbMY9wqUGsWucasO0RHn8jTYqRPH07Zjipob5WIz0AuYJ65NXY/A==",
 			"dev": true,
 			"license": "MIT"
 		},
@@ -8299,7 +8299,7 @@
 			],
 			"license": "MIT",
 			"devDependencies": {
-				"@rmenke/css-tokenizer-tests": "^1.2.0",
+				"@rmenke/css-tokenizer-tests": "^1.3.1",
 				"postcss": "^8.5.10",
 				"postcss-parser-tests": "^8.10.0"
 			},
diff --git a/packages/css-tokenizer/CHANGELOG.md b/packages/css-tokenizer/CHANGELOG.md
index c6d7842a98..6dc611e065 100644
--- a/packages/css-tokenizer/CHANGELOG.md
+++ b/packages/css-tokenizer/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changes to CSS Tokenizer
 
+### Unreleased (patch)
+
+- Fix handling of astral code points in `string-token` and `url-token` values.
+
 ### 4.0.0
 
 _January 14, 2026_
diff --git a/packages/css-tokenizer/dist/index.mjs b/packages/css-tokenizer/dist/index.mjs
index e0237c0b7e..b536aaf74d 100644
--- a/packages/css-tokenizer/dist/index.mjs
+++ b/packages/css-tokenizer/dist/index.mjs
@@ -1 +1 @@
-class ParseError extends Error{sourceStart;sourceEnd;parserState;constructor(e,n,t,o){super(e),this.name="ParseError",this.sourceStart=n,this.sourceEnd=t,this.parserState=o}}class ParseErrorWithToken extends ParseError{token;constructor(e,n,t,o,r){super(e,n,t,o),this.token=r}}const e={UnexpectedNewLineInString:"Unexpected newline while consuming a string token.",UnexpectedEOFInString:"Unexpected EOF while consuming a string token.",UnexpectedEOFInComment:"Unexpected EOF while consuming a comment.",UnexpectedEOFInURL:"Unexpected EOF while consuming a url token.",UnexpectedEOFInEscapedCodePoint:"Unexpected EOF while consuming an escaped code point.",UnexpectedCharacterInURL:"Unexpected character while consuming a url token.",InvalidEscapeSequenceInURL:"Invalid escape sequence while consuming a url token.",InvalidEscapeSequenceAfterBackslash:'Invalid escape sequence after "\\"'},n="undefined"!=typeof globalThis&&"structuredClone"in globalThis;function cloneTokens(e){return n?structuredClone(e):JSON.parse(JSON.stringify(e))}function stringify(...e){let n="";for(let t=0;t<e.length;t++)n+=e[t][1];return n}const t=13,o=45,r=10,i=43,s=65533;function checkIfFourCodePointsWouldStartCDO(e){return 60===e.source.codePointAt(e.cursor)&&33===e.source.codePointAt(e.cursor+1)&&e.source.codePointAt(e.cursor+2)===o&&e.source.codePointAt(e.cursor+3)===o}function isDigitCodePoint(e){return e>=48&&e<=57}function isUppercaseLetterCodePoint(e){return e>=65&&e<=90}function isLowercaseLetterCodePoint(e){return e>=97&&e<=122}function isHexDigitCodePoint(e){return e>=48&&e<=57||e>=97&&e<=102||e>=65&&e<=70}function isLetterCodePoint(e){return isLowercaseLetterCodePoint(e)||isUppercaseLetterCodePoint(e)}function isIdentStartCodePoint(e){return isLetterCodePoint(e)||isNonASCII_IdentCodePoint(e)||95===e}function isIdentCodePoint(e){return isIdentStartCodePoint(e)||isDigitCodePoint(e)||e===o}function isNonASCII_IdentCodePoint(e){return 183===e||8204===e||8205===e||8255===e||8256===e||8204===e||(192<=e&&e<=214||216<=e&&e<=246||248<=e&&e<=893||895<=e&&e<=8191||8304<=e&&e<=8591||11264<=e&&e<=12271||12289<=e&&e<=55295||63744<=e&&e<=64975||65008<=e&&e<=65533||(0===e||(!!isSurrogate(e)||e>=65536)))}function isNonPrintableCodePoint(e){return 11===e||127===e||0<=e&&e<=8||14<=e&&e<=31}function isNewLine(e){return e===r||e===t||12===e}function isWhitespace(e){return 32===e||e===r||9===e||e===t||12===e}function isSurrogate(e){return e>=55296&&e<=57343}function checkIfTwoCodePointsAreAValidEscape(e){return 92===e.source.codePointAt(e.cursor)&&!isNewLine(e.source.codePointAt(e.cursor+1)??-1)}function checkIfThreeCodePointsWouldStartAnIdentSequence(e,n){return n.source.codePointAt(n.cursor)===o?n.source.codePointAt(n.cursor+1)===o||(!!isIdentStartCodePoint(n.source.codePointAt(n.cursor+1)??-1)||92===n.source.codePointAt(n.cursor+1)&&!isNewLine(n.source.codePointAt(n.cursor+2)??-1)):!!isIdentStartCodePoint(n.source.codePointAt(n.cursor)??-1)||checkIfTwoCodePointsAreAValidEscape(n)}function checkIfThreeCodePointsWouldStartANumber(e){return e.source.codePointAt(e.cursor)===i||e.source.codePointAt(e.cursor)===o?!!isDigitCodePoint(e.source.codePointAt(e.cursor+1)??-1)||46===e.source.codePointAt(e.cursor+1)&&isDigitCodePoint(e.source.codePointAt(e.cursor+2)??-1):46===e.source.codePointAt(e.cursor)?isDigitCodePoint(e.source.codePointAt(e.cursor+1)??-1):isDigitCodePoint(e.source.codePointAt(e.cursor)??-1)}function checkIfTwoCodePointsStartAComment(e){return 47===e.source.codePointAt(e.cursor)&&42===e.source.codePointAt(e.cursor+1)}function checkIfThreeCodePointsWouldStartCDC(e){return e.source.codePointAt(e.cursor)===o&&e.source.codePointAt(e.cursor+1)===o&&62===e.source.codePointAt(e.cursor+2)}var c,a,u;function mirrorVariantType(e){switch(e){case c.OpenParen:return c.CloseParen;case c.CloseParen:return c.OpenParen;case c.OpenCurly:return c.CloseCurly;case c.CloseCurly:return c.OpenCurly;case c.OpenSquare:return c.CloseSquare;case c.CloseSquare:return c.OpenSquare;default:return null}}function mirrorVariant(e){switch(e[0]){case c.OpenParen:return[c.CloseParen,")",-1,-1,void 0];case c.CloseParen:return[c.OpenParen,"(",-1,-1,void 0];case c.OpenCurly:return[c.CloseCurly,"}",-1,-1,void 0];case c.CloseCurly:return[c.OpenCurly,"{",-1,-1,void 0];case c.OpenSquare:return[c.CloseSquare,"]",-1,-1,void 0];case c.CloseSquare:return[c.OpenSquare,"[",-1,-1,void 0];default:return null}}function consumeComment(n,t){for(t.advanceCodePoint(2);;){const o=t.readCodePoint();if(void 0===o){const o=[c.Comment,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,void 0];return n.onParseError(new ParseErrorWithToken(e.UnexpectedEOFInComment,t.representationStart,t.representationEnd,["4.3.2. Consume comments","Unexpected EOF"],o)),o}if(42===o&&(void 0!==t.source.codePointAt(t.cursor)&&47===t.source.codePointAt(t.cursor))){t.advanceCodePoint();break}}return[c.Comment,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,void 0]}function consumeEscapedCodePoint(n,o){const i=o.readCodePoint();if(void 0===i)return n.onParseError(new ParseError(e.UnexpectedEOFInEscapedCodePoint,o.representationStart,o.representationEnd,["4.3.7. Consume an escaped code point","Unexpected EOF"])),s;if(isHexDigitCodePoint(i)){const e=[i];let n;for(;void 0!==(n=o.source.codePointAt(o.cursor))&&isHexDigitCodePoint(n)&&e.length<6;)e.push(n),o.advanceCodePoint();isWhitespace(o.source.codePointAt(o.cursor)??-1)&&(o.source.codePointAt(o.cursor)===t&&o.source.codePointAt(o.cursor+1)===r&&o.advanceCodePoint(),o.advanceCodePoint());const c=parseInt(String.fromCodePoint(...e),16);return 0===c||isSurrogate(c)||c>1114111?s:c}return 0===i||isSurrogate(i)?s:i}function consumeIdentSequence(e,n){const t=[];for(;;){const o=n.source.codePointAt(n.cursor)??-1;if(0===o||isSurrogate(o))t.push(s),n.advanceCodePoint(+(o>65535)+1);else if(isIdentCodePoint(o))t.push(o),n.advanceCodePoint(+(o>65535)+1);else{if(!checkIfTwoCodePointsAreAValidEscape(n))return t;n.advanceCodePoint(),t.push(consumeEscapedCodePoint(e,n))}}}function consumeHashToken(e,n){n.advanceCodePoint();const t=n.source.codePointAt(n.cursor);if(void 0!==t&&(isIdentCodePoint(t)||checkIfTwoCodePointsAreAValidEscape(n))){let t=u.Unrestricted;checkIfThreeCodePointsWouldStartAnIdentSequence(0,n)&&(t=u.ID);const o=consumeIdentSequence(e,n);return[c.Hash,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:String.fromCodePoint(...o),type:t}]}return[c.Delim,"#",n.representationStart,n.representationEnd,{value:"#"}]}function consumeNumber(e,n){let t=a.Integer;for(n.source.codePointAt(n.cursor)!==i&&n.source.codePointAt(n.cursor)!==o||n.advanceCodePoint();isDigitCodePoint(n.source.codePointAt(n.cursor)??-1);)n.advanceCodePoint();if(46===n.source.codePointAt(n.cursor)&&isDigitCodePoint(n.source.codePointAt(n.cursor+1)??-1))for(n.advanceCodePoint(2),t=a.Number;isDigitCodePoint(n.source.codePointAt(n.cursor)??-1);)n.advanceCodePoint();if(101===n.source.codePointAt(n.cursor)||69===n.source.codePointAt(n.cursor)){if(isDigitCodePoint(n.source.codePointAt(n.cursor+1)??-1))n.advanceCodePoint(2);else{if(n.source.codePointAt(n.cursor+1)!==o&&n.source.codePointAt(n.cursor+1)!==i||!isDigitCodePoint(n.source.codePointAt(n.cursor+2)??-1))return t;n.advanceCodePoint(3)}for(t=a.Number;isDigitCodePoint(n.source.codePointAt(n.cursor)??-1);)n.advanceCodePoint()}return t}function consumeNumericToken(e,n){let t;{const e=n.source.codePointAt(n.cursor);e===o?t="-":e===i&&(t="+")}const r=consumeNumber(0,n),s=parseFloat(n.source.slice(n.representationStart,n.representationEnd+1));if(checkIfThreeCodePointsWouldStartAnIdentSequence(0,n)){const o=consumeIdentSequence(e,n);return[c.Dimension,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:s,signCharacter:t,type:r,unit:String.fromCodePoint(...o)}]}return 37===n.source.codePointAt(n.cursor)?(n.advanceCodePoint(),[c.Percentage,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:s,signCharacter:t}]):[c.Number,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:s,signCharacter:t,type:r}]}function consumeWhiteSpace(e){for(;isWhitespace(e.source.codePointAt(e.cursor)??-1);)e.advanceCodePoint();return[c.Whitespace,e.source.slice(e.representationStart,e.representationEnd+1),e.representationStart,e.representationEnd,void 0]}!function(e){e.Comment="comment",e.AtKeyword="at-keyword-token",e.BadString="bad-string-token",e.BadURL="bad-url-token",e.CDC="CDC-token",e.CDO="CDO-token",e.Colon="colon-token",e.Comma="comma-token",e.Delim="delim-token",e.Dimension="dimension-token",e.EOF="EOF-token",e.Function="function-token",e.Hash="hash-token",e.Ident="ident-token",e.Number="number-token",e.Percentage="percentage-token",e.Semicolon="semicolon-token",e.String="string-token",e.URL="url-token",e.Whitespace="whitespace-token",e.OpenParen="(-token",e.CloseParen=")-token",e.OpenSquare="[-token",e.CloseSquare="]-token",e.OpenCurly="{-token",e.CloseCurly="}-token",e.UnicodeRange="unicode-range-token"}(c||(c={})),function(e){e.Integer="integer",e.Number="number"}(a||(a={})),function(e){e.Unrestricted="unrestricted",e.ID="id"}(u||(u={}));class Reader{cursor=0;source="";representationStart=0;representationEnd=-1;constructor(e){this.source=e}advanceCodePoint(e=1){this.cursor=this.cursor+e,this.representationEnd=this.cursor-1}readCodePoint(){const e=this.source.codePointAt(this.cursor);if(void 0!==e)return this.cursor=this.cursor+1,this.representationEnd=this.cursor-1,e}unreadCodePoint(e=1){this.cursor=this.cursor-e,this.representationEnd=this.cursor-1}resetRepresentation(){this.representationStart=this.cursor,this.representationEnd=-1}}function consumeStringToken(n,o){let i="";const a=o.readCodePoint();for(;;){const u=o.readCodePoint();if(void 0===u){const t=[c.String,o.source.slice(o.representationStart,o.representationEnd+1),o.representationStart,o.representationEnd,{value:i}];return n.onParseError(new ParseErrorWithToken(e.UnexpectedEOFInString,o.representationStart,o.representationEnd,["4.3.5. Consume a string token","Unexpected EOF"],t)),t}if(isNewLine(u)){o.unreadCodePoint();const i=[c.BadString,o.source.slice(o.representationStart,o.representationEnd+1),o.representationStart,o.representationEnd,void 0];return n.onParseError(new ParseErrorWithToken(e.UnexpectedNewLineInString,o.representationStart,o.source.codePointAt(o.cursor)===t&&o.source.codePointAt(o.cursor+1)===r?o.representationEnd+2:o.representationEnd+1,["4.3.5. Consume a string token","Unexpected newline"],i)),i}if(u===a)return[c.String,o.source.slice(o.representationStart,o.representationEnd+1),o.representationStart,o.representationEnd,{value:i}];if(92!==u)0===u||isSurrogate(u)?i+=String.fromCodePoint(s):i+=String.fromCodePoint(u);else{if(void 0===o.source.codePointAt(o.cursor))continue;if(isNewLine(o.source.codePointAt(o.cursor)??-1)){o.source.codePointAt(o.cursor)===t&&o.source.codePointAt(o.cursor+1)===r&&o.advanceCodePoint(),o.advanceCodePoint();continue}i+=String.fromCodePoint(consumeEscapedCodePoint(n,o))}}}function checkIfCodePointsMatchURLIdent(e){return!(3!==e.length||117!==e[0]&&85!==e[0]||114!==e[1]&&82!==e[1]||108!==e[2]&&76!==e[2])}function consumeBadURL(e,n){for(;;){const t=n.source.codePointAt(n.cursor);if(void 0===t)return;if(41===t)return void n.advanceCodePoint();checkIfTwoCodePointsAreAValidEscape(n)?(n.advanceCodePoint(),consumeEscapedCodePoint(e,n)):n.advanceCodePoint()}}function consumeUrlToken(n,t){for(;isWhitespace(t.source.codePointAt(t.cursor)??-1);)t.advanceCodePoint();let o="";for(;;){if(void 0===t.source.codePointAt(t.cursor)){const r=[c.URL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,{value:o}];return n.onParseError(new ParseErrorWithToken(e.UnexpectedEOFInURL,t.representationStart,t.representationEnd,["4.3.6. Consume a url token","Unexpected EOF"],r)),r}if(41===t.source.codePointAt(t.cursor))return t.advanceCodePoint(),[c.URL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,{value:o}];if(isWhitespace(t.source.codePointAt(t.cursor)??-1)){for(t.advanceCodePoint();isWhitespace(t.source.codePointAt(t.cursor)??-1);)t.advanceCodePoint();if(void 0===t.source.codePointAt(t.cursor)){const r=[c.URL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,{value:o}];return n.onParseError(new ParseErrorWithToken(e.UnexpectedEOFInURL,t.representationStart,t.representationEnd,["4.3.6. Consume a url token","Consume as much whitespace as possible","Unexpected EOF"],r)),r}return 41===t.source.codePointAt(t.cursor)?(t.advanceCodePoint(),[c.URL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,{value:o}]):(consumeBadURL(n,t),[c.BadURL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,void 0])}const r=t.source.codePointAt(t.cursor);if(34===r||39===r||40===r||isNonPrintableCodePoint(r??-1)){consumeBadURL(n,t);const o=[c.BadURL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,void 0];return n.onParseError(new ParseErrorWithToken(e.UnexpectedCharacterInURL,t.representationStart,t.representationEnd,["4.3.6. Consume a url token","Unexpected U+0022 QUOTATION MARK (\"), U+0027 APOSTROPHE ('), U+0028 LEFT PARENTHESIS (() or non-printable code point"],o)),o}if(92===r){if(checkIfTwoCodePointsAreAValidEscape(t)){t.advanceCodePoint(),o+=String.fromCodePoint(consumeEscapedCodePoint(n,t));continue}consumeBadURL(n,t);const r=[c.BadURL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,void 0];return n.onParseError(new ParseErrorWithToken(e.InvalidEscapeSequenceInURL,t.representationStart,t.representationEnd,["4.3.6. Consume a url token","U+005C REVERSE SOLIDUS (\\)","The input stream does not start with a valid escape sequence"],r)),r}0===t.source.codePointAt(t.cursor)||isSurrogate(t.source.codePointAt(t.cursor)??-1)?(o+=String.fromCodePoint(s),t.advanceCodePoint()):(o+=t.source[t.cursor],t.advanceCodePoint())}}function consumeIdentLikeToken(e,n){const t=consumeIdentSequence(e,n);if(40!==n.source.codePointAt(n.cursor))return[c.Ident,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:String.fromCodePoint(...t)}];if(checkIfCodePointsMatchURLIdent(t)){n.advanceCodePoint();let o=0;for(;;){const e=isWhitespace(n.source.codePointAt(n.cursor)??-1),r=isWhitespace(n.source.codePointAt(n.cursor+1)??-1);if(e&&r){o+=1,n.advanceCodePoint(1);continue}const i=e?n.source.codePointAt(n.cursor+1):n.source.codePointAt(n.cursor);if(34===i||39===i)return o>0&&n.unreadCodePoint(o),[c.Function,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:String.fromCodePoint(...t)}];break}return consumeUrlToken(e,n)}return n.advanceCodePoint(),[c.Function,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:String.fromCodePoint(...t)}]}function checkIfThreeCodePointsWouldStartAUnicodeRange(e){return!(117!==e.source.codePointAt(e.cursor)&&85!==e.source.codePointAt(e.cursor)||e.source.codePointAt(e.cursor+1)!==i||63!==e.source.codePointAt(e.cursor+2)&&!isHexDigitCodePoint(e.source.codePointAt(e.cursor+2)??-1))}function consumeUnicodeRangeToken(e,n){n.advanceCodePoint(2);const t=[],r=[];let i;for(;void 0!==(i=n.source.codePointAt(n.cursor))&&t.length<6&&isHexDigitCodePoint(i);)t.push(i),n.advanceCodePoint();for(;void 0!==(i=n.source.codePointAt(n.cursor))&&t.length<6&&63===i;)0===r.length&&r.push(...t),t.push(48),r.push(70),n.advanceCodePoint();if(!r.length&&n.source.codePointAt(n.cursor)===o&&isHexDigitCodePoint(n.source.codePointAt(n.cursor+1)??-1))for(n.advanceCodePoint();void 0!==(i=n.source.codePointAt(n.cursor))&&r.length<6&&isHexDigitCodePoint(i);)r.push(i),n.advanceCodePoint();if(!r.length){const e=parseInt(String.fromCodePoint(...t),16);return[c.UnicodeRange,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{startOfRange:e,endOfRange:e}]}const s=parseInt(String.fromCodePoint(...t),16),a=parseInt(String.fromCodePoint(...r),16);return[c.UnicodeRange,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{startOfRange:s,endOfRange:a}]}function tokenize(e,n){const t=tokenizer(e,n),o=[];for(;!t.endOfFile();)o.push(t.nextToken());return o.push(t.nextToken()),o}function tokenizer(n,s){const a=n.css.valueOf(),u=n.unicodeRangesAllowed??!1,d=new Reader(a),p={onParseError:s?.onParseError??noop};return{nextToken:function nextToken(){d.resetRepresentation();const n=d.source.codePointAt(d.cursor);if(void 0===n)return[c.EOF,"",-1,-1,void 0];if(47===n&&checkIfTwoCodePointsStartAComment(d))return consumeComment(p,d);if(u&&(117===n||85===n)&&checkIfThreeCodePointsWouldStartAUnicodeRange(d))return consumeUnicodeRangeToken(0,d);if(isIdentStartCodePoint(n))return consumeIdentLikeToken(p,d);if(isDigitCodePoint(n))return consumeNumericToken(p,d);switch(n){case 44:return d.advanceCodePoint(),[c.Comma,",",d.representationStart,d.representationEnd,void 0];case 58:return d.advanceCodePoint(),[c.Colon,":",d.representationStart,d.representationEnd,void 0];case 59:return d.advanceCodePoint(),[c.Semicolon,";",d.representationStart,d.representationEnd,void 0];case 40:return d.advanceCodePoint(),[c.OpenParen,"(",d.representationStart,d.representationEnd,void 0];case 41:return d.advanceCodePoint(),[c.CloseParen,")",d.representationStart,d.representationEnd,void 0];case 91:return d.advanceCodePoint(),[c.OpenSquare,"[",d.representationStart,d.representationEnd,void 0];case 93:return d.advanceCodePoint(),[c.CloseSquare,"]",d.representationStart,d.representationEnd,void 0];case 123:return d.advanceCodePoint(),[c.OpenCurly,"{",d.representationStart,d.representationEnd,void 0];case 125:return d.advanceCodePoint(),[c.CloseCurly,"}",d.representationStart,d.representationEnd,void 0];case 39:case 34:return consumeStringToken(p,d);case 35:return consumeHashToken(p,d);case i:case 46:return checkIfThreeCodePointsWouldStartANumber(d)?consumeNumericToken(p,d):(d.advanceCodePoint(),[c.Delim,d.source[d.representationStart],d.representationStart,d.representationEnd,{value:d.source[d.representationStart]}]);case r:case t:case 12:case 9:case 32:return consumeWhiteSpace(d);case o:return checkIfThreeCodePointsWouldStartANumber(d)?consumeNumericToken(p,d):checkIfThreeCodePointsWouldStartCDC(d)?(d.advanceCodePoint(3),[c.CDC,"--\x3e",d.representationStart,d.representationEnd,void 0]):checkIfThreeCodePointsWouldStartAnIdentSequence(0,d)?consumeIdentLikeToken(p,d):(d.advanceCodePoint(),[c.Delim,"-",d.representationStart,d.representationEnd,{value:"-"}]);case 60:return checkIfFourCodePointsWouldStartCDO(d)?(d.advanceCodePoint(4),[c.CDO,"\x3c!--",d.representationStart,d.representationEnd,void 0]):(d.advanceCodePoint(),[c.Delim,"<",d.representationStart,d.representationEnd,{value:"<"}]);case 64:if(d.advanceCodePoint(),checkIfThreeCodePointsWouldStartAnIdentSequence(0,d)){const e=consumeIdentSequence(p,d);return[c.AtKeyword,d.source.slice(d.representationStart,d.representationEnd+1),d.representationStart,d.representationEnd,{value:String.fromCodePoint(...e)}]}return[c.Delim,"@",d.representationStart,d.representationEnd,{value:"@"}];case 92:{if(checkIfTwoCodePointsAreAValidEscape(d))return consumeIdentLikeToken(p,d);d.advanceCodePoint();const n=[c.Delim,"\\",d.representationStart,d.representationEnd,{value:"\\"}];return p.onParseError(new ParseErrorWithToken(e.InvalidEscapeSequenceAfterBackslash,d.representationStart,d.representationEnd,["4.3.1. Consume a token","U+005C REVERSE SOLIDUS (\\)","The input stream does not start with a valid escape sequence"],n)),n}}return d.advanceCodePoint(),[c.Delim,d.source[d.representationStart],d.representationStart,d.representationEnd,{value:d.source[d.representationStart]}]},endOfFile:function endOfFile(){return void 0===d.source.codePointAt(d.cursor)}}}function noop(){}function mutateIdent(e,n){const t=[];for(const e of n)t.push(e.codePointAt(0));const o=String.fromCodePoint(...serializeIdent(t));e[1]=o,e[4].value=n}function mutateUnit(e,n){const t=[];for(const e of n)t.push(e.codePointAt(0));const o=serializeIdent(t);101===o[0]&&insertEscapedCodePoint(o,0,o[0]);const r=String.fromCodePoint(...o),i="+"===e[4].signCharacter?e[4].signCharacter:"",s=e[4].value.toString();e[1]=`${i}${s}${r}`,e[4].unit=n}function serializeIdent(e){let n;if(0===e[0])e.splice(0,1,s),n=1;else if(e[0]===o&&e[1]===o)n=2;else if(e[0]===o&&e[1])n=2,isIdentStartCodePoint(e[1])||(n+=insertEscapedCodePoint(e,1,e[1]));else{if(e[0]===o&&!e[1])return[92,e[0]];isIdentStartCodePoint(e[0])?n=1:(n=1,n+=insertEscapedCodePoint(e,0,e[0]))}for(let t=n;t<e.length;t++)0!==e[t]?isIdentCodePoint(e[t])||(t+=insertEscapedCharacter(e,t,e[t])):(e.splice(t,1,s),t++);return e}function insertEscapedCharacter(e,n,t){return e.splice(n,1,92,t),1}function insertEscapedCodePoint(e,n,t){const o=t.toString(16),r=[];for(const e of o)r.push(e.codePointAt(0));return e.splice(n,1,92,...r,32),1+r.length}const d=Object.values(c);function isToken(e){return!!Array.isArray(e)&&(!(e.length<4)&&(!!d.includes(e[0])&&("string"==typeof e[1]&&("number"==typeof e[2]&&"number"==typeof e[3]))))}function isTokenNumeric(e){if(!e)return!1;switch(e[0]){case c.Dimension:case c.Number:case c.Percentage:return!0;default:return!1}}function isTokenWhiteSpaceOrComment(e){if(!e)return!1;switch(e[0]){case c.Whitespace:case c.Comment:return!0;default:return!1}}function isTokenAtKeyword(e){return!!e&&e[0]===c.AtKeyword}function isTokenBadString(e){return!!e&&e[0]===c.BadString}function isTokenBadURL(e){return!!e&&e[0]===c.BadURL}function isTokenCDC(e){return!!e&&e[0]===c.CDC}function isTokenCDO(e){return!!e&&e[0]===c.CDO}function isTokenColon(e){return!!e&&e[0]===c.Colon}function isTokenComma(e){return!!e&&e[0]===c.Comma}function isTokenComment(e){return!!e&&e[0]===c.Comment}function isTokenDelim(e){return!!e&&e[0]===c.Delim}function isTokenDimension(e){return!!e&&e[0]===c.Dimension}function isTokenEOF(e){return!!e&&e[0]===c.EOF}function isTokenFunction(e){return!!e&&e[0]===c.Function}function isTokenHash(e){return!!e&&e[0]===c.Hash}function isTokenIdent(e){return!!e&&e[0]===c.Ident}function isTokenNumber(e){return!!e&&e[0]===c.Number}function isTokenPercentage(e){return!!e&&e[0]===c.Percentage}function isTokenSemicolon(e){return!!e&&e[0]===c.Semicolon}function isTokenString(e){return!!e&&e[0]===c.String}function isTokenURL(e){return!!e&&e[0]===c.URL}function isTokenWhitespace(e){return!!e&&e[0]===c.Whitespace}function isTokenOpenParen(e){return!!e&&e[0]===c.OpenParen}function isTokenCloseParen(e){return!!e&&e[0]===c.CloseParen}function isTokenOpenSquare(e){return!!e&&e[0]===c.OpenSquare}function isTokenCloseSquare(e){return!!e&&e[0]===c.CloseSquare}function isTokenOpenCurly(e){return!!e&&e[0]===c.OpenCurly}function isTokenCloseCurly(e){return!!e&&e[0]===c.CloseCurly}function isTokenUnicodeRange(e){return!!e&&e[0]===c.UnicodeRange}export{u as HashType,a as NumberType,ParseError,e as ParseErrorMessage,ParseErrorWithToken,c as TokenType,cloneTokens,isToken,isTokenAtKeyword,isTokenBadString,isTokenBadURL,isTokenCDC,isTokenCDO,isTokenCloseCurly,isTokenCloseParen,isTokenCloseSquare,isTokenColon,isTokenComma,isTokenComment,isTokenDelim,isTokenDimension,isTokenEOF,isTokenFunction,isTokenHash,isTokenIdent,isTokenNumber,isTokenNumeric,isTokenOpenCurly,isTokenOpenParen,isTokenOpenSquare,isTokenPercentage,isTokenSemicolon,isTokenString,isTokenURL,isTokenUnicodeRange,isTokenWhiteSpaceOrComment,isTokenWhitespace,mirrorVariant,mirrorVariantType,mutateIdent,mutateUnit,stringify,tokenize,tokenizer};
+class ParseError extends Error{sourceStart;sourceEnd;parserState;constructor(e,n,t,o){super(e),this.name="ParseError",this.sourceStart=n,this.sourceEnd=t,this.parserState=o}}class ParseErrorWithToken extends ParseError{token;constructor(e,n,t,o,r){super(e,n,t,o),this.token=r}}const e={UnexpectedNewLineInString:"Unexpected newline while consuming a string token.",UnexpectedEOFInString:"Unexpected EOF while consuming a string token.",UnexpectedEOFInComment:"Unexpected EOF while consuming a comment.",UnexpectedEOFInURL:"Unexpected EOF while consuming a url token.",UnexpectedEOFInEscapedCodePoint:"Unexpected EOF while consuming an escaped code point.",UnexpectedCharacterInURL:"Unexpected character while consuming a url token.",InvalidEscapeSequenceInURL:"Invalid escape sequence while consuming a url token.",InvalidEscapeSequenceAfterBackslash:'Invalid escape sequence after "\\"'},n="undefined"!=typeof globalThis&&"structuredClone"in globalThis;function cloneTokens(e){return n?structuredClone(e):JSON.parse(JSON.stringify(e))}function stringify(...e){let n="";for(let t=0;t<e.length;t++)n+=e[t][1];return n}const t=13,o=45,r=10,i=43,s=65533;function checkIfFourCodePointsWouldStartCDO(e){return 60===e.source.codePointAt(e.cursor)&&33===e.source.codePointAt(e.cursor+1)&&e.source.codePointAt(e.cursor+2)===o&&e.source.codePointAt(e.cursor+3)===o}function isDigitCodePoint(e){return e>=48&&e<=57}function isUppercaseLetterCodePoint(e){return e>=65&&e<=90}function isLowercaseLetterCodePoint(e){return e>=97&&e<=122}function isHexDigitCodePoint(e){return e>=48&&e<=57||e>=97&&e<=102||e>=65&&e<=70}function isLetterCodePoint(e){return isLowercaseLetterCodePoint(e)||isUppercaseLetterCodePoint(e)}function isIdentStartCodePoint(e){return isLetterCodePoint(e)||isNonASCII_IdentCodePoint(e)||95===e}function isIdentCodePoint(e){return isIdentStartCodePoint(e)||isDigitCodePoint(e)||e===o}function isNonASCII_IdentCodePoint(e){return 183===e||8204===e||8205===e||8255===e||8256===e||8204===e||(192<=e&&e<=214||216<=e&&e<=246||248<=e&&e<=893||895<=e&&e<=8191||8304<=e&&e<=8591||11264<=e&&e<=12271||12289<=e&&e<=55295||63744<=e&&e<=64975||65008<=e&&e<=65533||(0===e||(!!isSurrogate(e)||e>=65536)))}function isNonPrintableCodePoint(e){return 11===e||127===e||0<=e&&e<=8||14<=e&&e<=31}function isNewLine(e){return e===r||e===t||12===e}function isWhitespace(e){return 32===e||e===r||9===e||e===t||12===e}function isSurrogate(e){return e>=55296&&e<=57343}function checkIfTwoCodePointsAreAValidEscape(e){return 92===e.source.codePointAt(e.cursor)&&!isNewLine(e.source.codePointAt(e.cursor+1)??-1)}function checkIfThreeCodePointsWouldStartAnIdentSequence(e,n){return n.source.codePointAt(n.cursor)===o?n.source.codePointAt(n.cursor+1)===o||(!!isIdentStartCodePoint(n.source.codePointAt(n.cursor+1)??-1)||92===n.source.codePointAt(n.cursor+1)&&!isNewLine(n.source.codePointAt(n.cursor+2)??-1)):!!isIdentStartCodePoint(n.source.codePointAt(n.cursor)??-1)||checkIfTwoCodePointsAreAValidEscape(n)}function checkIfThreeCodePointsWouldStartANumber(e){return e.source.codePointAt(e.cursor)===i||e.source.codePointAt(e.cursor)===o?!!isDigitCodePoint(e.source.codePointAt(e.cursor+1)??-1)||46===e.source.codePointAt(e.cursor+1)&&isDigitCodePoint(e.source.codePointAt(e.cursor+2)??-1):46===e.source.codePointAt(e.cursor)?isDigitCodePoint(e.source.codePointAt(e.cursor+1)??-1):isDigitCodePoint(e.source.codePointAt(e.cursor)??-1)}function checkIfTwoCodePointsStartAComment(e){return 47===e.source.codePointAt(e.cursor)&&42===e.source.codePointAt(e.cursor+1)}function checkIfThreeCodePointsWouldStartCDC(e){return e.source.codePointAt(e.cursor)===o&&e.source.codePointAt(e.cursor+1)===o&&62===e.source.codePointAt(e.cursor+2)}var c,a,u;function mirrorVariantType(e){switch(e){case c.OpenParen:return c.CloseParen;case c.CloseParen:return c.OpenParen;case c.OpenCurly:return c.CloseCurly;case c.CloseCurly:return c.OpenCurly;case c.OpenSquare:return c.CloseSquare;case c.CloseSquare:return c.OpenSquare;default:return null}}function mirrorVariant(e){switch(e[0]){case c.OpenParen:return[c.CloseParen,")",-1,-1,void 0];case c.CloseParen:return[c.OpenParen,"(",-1,-1,void 0];case c.OpenCurly:return[c.CloseCurly,"}",-1,-1,void 0];case c.CloseCurly:return[c.OpenCurly,"{",-1,-1,void 0];case c.OpenSquare:return[c.CloseSquare,"]",-1,-1,void 0];case c.CloseSquare:return[c.OpenSquare,"[",-1,-1,void 0];default:return null}}function consumeComment(n,t){for(t.advanceCodePoint(2);;){const o=t.readCodePoint();if(void 0===o){const o=[c.Comment,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,void 0];return n.onParseError(new ParseErrorWithToken(e.UnexpectedEOFInComment,t.representationStart,t.representationEnd,["4.3.2. Consume comments","Unexpected EOF"],o)),o}if(42===o&&(void 0!==t.source.codePointAt(t.cursor)&&47===t.source.codePointAt(t.cursor))){t.advanceCodePoint();break}}return[c.Comment,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,void 0]}function consumeEscapedCodePoint(n,o){const i=o.readCodePoint();if(void 0===i)return n.onParseError(new ParseError(e.UnexpectedEOFInEscapedCodePoint,o.representationStart,o.representationEnd,["4.3.7. Consume an escaped code point","Unexpected EOF"])),s;if(isHexDigitCodePoint(i)){const e=[i];let n;for(;void 0!==(n=o.source.codePointAt(o.cursor))&&isHexDigitCodePoint(n)&&e.length<6;)e.push(n),o.advanceCodePoint();isWhitespace(o.source.codePointAt(o.cursor)??-1)&&(o.source.codePointAt(o.cursor)===t&&o.source.codePointAt(o.cursor+1)===r&&o.advanceCodePoint(),o.advanceCodePoint());const c=parseInt(String.fromCodePoint(...e),16);return 0===c||isSurrogate(c)||c>1114111?s:c}return 0===i||isSurrogate(i)?s:i}function consumeIdentSequence(e,n){const t=[];for(;;){const o=n.source.codePointAt(n.cursor)??-1;if(0===o||isSurrogate(o))t.push(s),n.advanceCodePoint(+(o>65535)+1);else if(isIdentCodePoint(o))t.push(o),n.advanceCodePoint(+(o>65535)+1);else{if(!checkIfTwoCodePointsAreAValidEscape(n))return t;n.advanceCodePoint(),t.push(consumeEscapedCodePoint(e,n))}}}function consumeHashToken(e,n){n.advanceCodePoint();const t=n.source.codePointAt(n.cursor);if(void 0!==t&&(isIdentCodePoint(t)||checkIfTwoCodePointsAreAValidEscape(n))){let t=u.Unrestricted;checkIfThreeCodePointsWouldStartAnIdentSequence(0,n)&&(t=u.ID);const o=consumeIdentSequence(e,n);return[c.Hash,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:String.fromCodePoint(...o),type:t}]}return[c.Delim,"#",n.representationStart,n.representationEnd,{value:"#"}]}function consumeNumber(e,n){let t=a.Integer;for(n.source.codePointAt(n.cursor)!==i&&n.source.codePointAt(n.cursor)!==o||n.advanceCodePoint();isDigitCodePoint(n.source.codePointAt(n.cursor)??-1);)n.advanceCodePoint();if(46===n.source.codePointAt(n.cursor)&&isDigitCodePoint(n.source.codePointAt(n.cursor+1)??-1))for(n.advanceCodePoint(2),t=a.Number;isDigitCodePoint(n.source.codePointAt(n.cursor)??-1);)n.advanceCodePoint();if(101===n.source.codePointAt(n.cursor)||69===n.source.codePointAt(n.cursor)){if(isDigitCodePoint(n.source.codePointAt(n.cursor+1)??-1))n.advanceCodePoint(2);else{if(n.source.codePointAt(n.cursor+1)!==o&&n.source.codePointAt(n.cursor+1)!==i||!isDigitCodePoint(n.source.codePointAt(n.cursor+2)??-1))return t;n.advanceCodePoint(3)}for(t=a.Number;isDigitCodePoint(n.source.codePointAt(n.cursor)??-1);)n.advanceCodePoint()}return t}function consumeNumericToken(e,n){let t;{const e=n.source.codePointAt(n.cursor);e===o?t="-":e===i&&(t="+")}const r=consumeNumber(0,n),s=parseFloat(n.source.slice(n.representationStart,n.representationEnd+1));if(checkIfThreeCodePointsWouldStartAnIdentSequence(0,n)){const o=consumeIdentSequence(e,n);return[c.Dimension,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:s,signCharacter:t,type:r,unit:String.fromCodePoint(...o)}]}return 37===n.source.codePointAt(n.cursor)?(n.advanceCodePoint(),[c.Percentage,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:s,signCharacter:t}]):[c.Number,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:s,signCharacter:t,type:r}]}function consumeWhiteSpace(e){for(;isWhitespace(e.source.codePointAt(e.cursor)??-1);)e.advanceCodePoint();return[c.Whitespace,e.source.slice(e.representationStart,e.representationEnd+1),e.representationStart,e.representationEnd,void 0]}!function(e){e.Comment="comment",e.AtKeyword="at-keyword-token",e.BadString="bad-string-token",e.BadURL="bad-url-token",e.CDC="CDC-token",e.CDO="CDO-token",e.Colon="colon-token",e.Comma="comma-token",e.Delim="delim-token",e.Dimension="dimension-token",e.EOF="EOF-token",e.Function="function-token",e.Hash="hash-token",e.Ident="ident-token",e.Number="number-token",e.Percentage="percentage-token",e.Semicolon="semicolon-token",e.String="string-token",e.URL="url-token",e.Whitespace="whitespace-token",e.OpenParen="(-token",e.CloseParen=")-token",e.OpenSquare="[-token",e.CloseSquare="]-token",e.OpenCurly="{-token",e.CloseCurly="}-token",e.UnicodeRange="unicode-range-token"}(c||(c={})),function(e){e.Integer="integer",e.Number="number"}(a||(a={})),function(e){e.Unrestricted="unrestricted",e.ID="id"}(u||(u={}));class Reader{cursor=0;source="";representationStart=0;representationEnd=-1;constructor(e){this.source=e}advanceCodePoint(e=1){this.cursor=this.cursor+e,this.representationEnd=this.cursor-1}readCodePoint(){const e=this.source.codePointAt(this.cursor);if(void 0!==e)return this.cursor=this.cursor+1+ +(e>65535),this.representationEnd=this.cursor-1,e}unreadCodePoint(e=1){this.cursor=this.cursor-e,this.representationEnd=this.cursor-1}resetRepresentation(){this.representationStart=this.cursor,this.representationEnd=-1}}function consumeStringToken(n,o){let i="";const a=o.readCodePoint();for(;;){const u=o.readCodePoint();if(void 0===u){const t=[c.String,o.source.slice(o.representationStart,o.representationEnd+1),o.representationStart,o.representationEnd,{value:i}];return n.onParseError(new ParseErrorWithToken(e.UnexpectedEOFInString,o.representationStart,o.representationEnd,["4.3.5. Consume a string token","Unexpected EOF"],t)),t}if(isNewLine(u)){o.unreadCodePoint();const i=[c.BadString,o.source.slice(o.representationStart,o.representationEnd+1),o.representationStart,o.representationEnd,void 0];return n.onParseError(new ParseErrorWithToken(e.UnexpectedNewLineInString,o.representationStart,o.source.codePointAt(o.cursor)===t&&o.source.codePointAt(o.cursor+1)===r?o.representationEnd+2:o.representationEnd+1,["4.3.5. Consume a string token","Unexpected newline"],i)),i}if(u===a)return[c.String,o.source.slice(o.representationStart,o.representationEnd+1),o.representationStart,o.representationEnd,{value:i}];if(92!==u)0===u||isSurrogate(u)?i+=String.fromCodePoint(s):i+=String.fromCodePoint(u);else{if(void 0===o.source.codePointAt(o.cursor))continue;if(isNewLine(o.source.codePointAt(o.cursor)??-1)){o.source.codePointAt(o.cursor)===t&&o.source.codePointAt(o.cursor+1)===r&&o.advanceCodePoint(),o.advanceCodePoint();continue}i+=String.fromCodePoint(consumeEscapedCodePoint(n,o))}}}function checkIfCodePointsMatchURLIdent(e){return!(3!==e.length||117!==e[0]&&85!==e[0]||114!==e[1]&&82!==e[1]||108!==e[2]&&76!==e[2])}function consumeBadURL(e,n){for(;;){const t=n.source.codePointAt(n.cursor);if(void 0===t)return;if(41===t)return void n.advanceCodePoint();checkIfTwoCodePointsAreAValidEscape(n)?(n.advanceCodePoint(),consumeEscapedCodePoint(e,n)):n.advanceCodePoint()}}function consumeUrlToken(n,t){for(;isWhitespace(t.source.codePointAt(t.cursor)??-1);)t.advanceCodePoint();let o="";for(;;){if(void 0===t.source.codePointAt(t.cursor)){const r=[c.URL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,{value:o}];return n.onParseError(new ParseErrorWithToken(e.UnexpectedEOFInURL,t.representationStart,t.representationEnd,["4.3.6. Consume a url token","Unexpected EOF"],r)),r}if(41===t.source.codePointAt(t.cursor))return t.advanceCodePoint(),[c.URL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,{value:o}];if(isWhitespace(t.source.codePointAt(t.cursor)??-1)){for(t.advanceCodePoint();isWhitespace(t.source.codePointAt(t.cursor)??-1);)t.advanceCodePoint();if(void 0===t.source.codePointAt(t.cursor)){const r=[c.URL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,{value:o}];return n.onParseError(new ParseErrorWithToken(e.UnexpectedEOFInURL,t.representationStart,t.representationEnd,["4.3.6. Consume a url token","Consume as much whitespace as possible","Unexpected EOF"],r)),r}return 41===t.source.codePointAt(t.cursor)?(t.advanceCodePoint(),[c.URL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,{value:o}]):(consumeBadURL(n,t),[c.BadURL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,void 0])}const r=t.source.codePointAt(t.cursor);if(34===r||39===r||40===r||isNonPrintableCodePoint(r??-1)){consumeBadURL(n,t);const o=[c.BadURL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,void 0];return n.onParseError(new ParseErrorWithToken(e.UnexpectedCharacterInURL,t.representationStart,t.representationEnd,["4.3.6. Consume a url token","Unexpected U+0022 QUOTATION MARK (\"), U+0027 APOSTROPHE ('), U+0028 LEFT PARENTHESIS (() or non-printable code point"],o)),o}if(92===r){if(checkIfTwoCodePointsAreAValidEscape(t)){t.advanceCodePoint(),o+=String.fromCodePoint(consumeEscapedCodePoint(n,t));continue}consumeBadURL(n,t);const r=[c.BadURL,t.source.slice(t.representationStart,t.representationEnd+1),t.representationStart,t.representationEnd,void 0];return n.onParseError(new ParseErrorWithToken(e.InvalidEscapeSequenceInURL,t.representationStart,t.representationEnd,["4.3.6. Consume a url token","U+005C REVERSE SOLIDUS (\\)","The input stream does not start with a valid escape sequence"],r)),r}0===r||isSurrogate(r??-1)?(o+=String.fromCodePoint(s),t.advanceCodePoint(+((r??-1)>65535)+1)):(o+=String.fromCodePoint(r??-1),t.advanceCodePoint(+((r??-1)>65535)+1))}}function consumeIdentLikeToken(e,n){const t=consumeIdentSequence(e,n);if(40!==n.source.codePointAt(n.cursor))return[c.Ident,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:String.fromCodePoint(...t)}];if(checkIfCodePointsMatchURLIdent(t)){n.advanceCodePoint();let o=0;for(;;){const e=isWhitespace(n.source.codePointAt(n.cursor)??-1),r=isWhitespace(n.source.codePointAt(n.cursor+1)??-1);if(e&&r){o+=1,n.advanceCodePoint(1);continue}const i=e?n.source.codePointAt(n.cursor+1):n.source.codePointAt(n.cursor);if(34===i||39===i)return o>0&&n.unreadCodePoint(o),[c.Function,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:String.fromCodePoint(...t)}];break}return consumeUrlToken(e,n)}return n.advanceCodePoint(),[c.Function,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{value:String.fromCodePoint(...t)}]}function checkIfThreeCodePointsWouldStartAUnicodeRange(e){return!(117!==e.source.codePointAt(e.cursor)&&85!==e.source.codePointAt(e.cursor)||e.source.codePointAt(e.cursor+1)!==i||63!==e.source.codePointAt(e.cursor+2)&&!isHexDigitCodePoint(e.source.codePointAt(e.cursor+2)??-1))}function consumeUnicodeRangeToken(e,n){n.advanceCodePoint(2);const t=[],r=[];let i;for(;void 0!==(i=n.source.codePointAt(n.cursor))&&t.length<6&&isHexDigitCodePoint(i);)t.push(i),n.advanceCodePoint();for(;void 0!==(i=n.source.codePointAt(n.cursor))&&t.length<6&&63===i;)0===r.length&&r.push(...t),t.push(48),r.push(70),n.advanceCodePoint();if(!r.length&&n.source.codePointAt(n.cursor)===o&&isHexDigitCodePoint(n.source.codePointAt(n.cursor+1)??-1))for(n.advanceCodePoint();void 0!==(i=n.source.codePointAt(n.cursor))&&r.length<6&&isHexDigitCodePoint(i);)r.push(i),n.advanceCodePoint();if(!r.length){const e=parseInt(String.fromCodePoint(...t),16);return[c.UnicodeRange,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{startOfRange:e,endOfRange:e}]}const s=parseInt(String.fromCodePoint(...t),16),a=parseInt(String.fromCodePoint(...r),16);return[c.UnicodeRange,n.source.slice(n.representationStart,n.representationEnd+1),n.representationStart,n.representationEnd,{startOfRange:s,endOfRange:a}]}function tokenize(e,n){const t=tokenizer(e,n),o=[];for(;!t.endOfFile();)o.push(t.nextToken());return o.push(t.nextToken()),o}function tokenizer(n,s){const a=n.css.valueOf(),u=n.unicodeRangesAllowed??!1,d=new Reader(a),p={onParseError:s?.onParseError??noop};return{nextToken:function nextToken(){d.resetRepresentation();const n=d.source.codePointAt(d.cursor);if(void 0===n)return[c.EOF,"",-1,-1,void 0];if(47===n&&checkIfTwoCodePointsStartAComment(d))return consumeComment(p,d);if(u&&(117===n||85===n)&&checkIfThreeCodePointsWouldStartAUnicodeRange(d))return consumeUnicodeRangeToken(0,d);if(isIdentStartCodePoint(n))return consumeIdentLikeToken(p,d);if(isDigitCodePoint(n))return consumeNumericToken(p,d);switch(n){case 44:return d.advanceCodePoint(),[c.Comma,",",d.representationStart,d.representationEnd,void 0];case 58:return d.advanceCodePoint(),[c.Colon,":",d.representationStart,d.representationEnd,void 0];case 59:return d.advanceCodePoint(),[c.Semicolon,";",d.representationStart,d.representationEnd,void 0];case 40:return d.advanceCodePoint(),[c.OpenParen,"(",d.representationStart,d.representationEnd,void 0];case 41:return d.advanceCodePoint(),[c.CloseParen,")",d.representationStart,d.representationEnd,void 0];case 91:return d.advanceCodePoint(),[c.OpenSquare,"[",d.representationStart,d.representationEnd,void 0];case 93:return d.advanceCodePoint(),[c.CloseSquare,"]",d.representationStart,d.representationEnd,void 0];case 123:return d.advanceCodePoint(),[c.OpenCurly,"{",d.representationStart,d.representationEnd,void 0];case 125:return d.advanceCodePoint(),[c.CloseCurly,"}",d.representationStart,d.representationEnd,void 0];case 39:case 34:return consumeStringToken(p,d);case 35:return consumeHashToken(p,d);case i:case 46:return checkIfThreeCodePointsWouldStartANumber(d)?consumeNumericToken(p,d):(d.advanceCodePoint(),[c.Delim,d.source[d.representationStart],d.representationStart,d.representationEnd,{value:d.source[d.representationStart]}]);case r:case t:case 12:case 9:case 32:return consumeWhiteSpace(d);case o:return checkIfThreeCodePointsWouldStartANumber(d)?consumeNumericToken(p,d):checkIfThreeCodePointsWouldStartCDC(d)?(d.advanceCodePoint(3),[c.CDC,"--\x3e",d.representationStart,d.representationEnd,void 0]):checkIfThreeCodePointsWouldStartAnIdentSequence(0,d)?consumeIdentLikeToken(p,d):(d.advanceCodePoint(),[c.Delim,"-",d.representationStart,d.representationEnd,{value:"-"}]);case 60:return checkIfFourCodePointsWouldStartCDO(d)?(d.advanceCodePoint(4),[c.CDO,"\x3c!--",d.representationStart,d.representationEnd,void 0]):(d.advanceCodePoint(),[c.Delim,"<",d.representationStart,d.representationEnd,{value:"<"}]);case 64:if(d.advanceCodePoint(),checkIfThreeCodePointsWouldStartAnIdentSequence(0,d)){const e=consumeIdentSequence(p,d);return[c.AtKeyword,d.source.slice(d.representationStart,d.representationEnd+1),d.representationStart,d.representationEnd,{value:String.fromCodePoint(...e)}]}return[c.Delim,"@",d.representationStart,d.representationEnd,{value:"@"}];case 92:{if(checkIfTwoCodePointsAreAValidEscape(d))return consumeIdentLikeToken(p,d);d.advanceCodePoint();const n=[c.Delim,"\\",d.representationStart,d.representationEnd,{value:"\\"}];return p.onParseError(new ParseErrorWithToken(e.InvalidEscapeSequenceAfterBackslash,d.representationStart,d.representationEnd,["4.3.1. Consume a token","U+005C REVERSE SOLIDUS (\\)","The input stream does not start with a valid escape sequence"],n)),n}}return d.advanceCodePoint(),[c.Delim,d.source[d.representationStart],d.representationStart,d.representationEnd,{value:d.source[d.representationStart]}]},endOfFile:function endOfFile(){return void 0===d.source.codePointAt(d.cursor)}}}function noop(){}function mutateIdent(e,n){const t=[];for(const e of n)t.push(e.codePointAt(0));const o=String.fromCodePoint(...serializeIdent(t));e[1]=o,e[4].value=n}function mutateUnit(e,n){const t=[];for(const e of n)t.push(e.codePointAt(0));const o=serializeIdent(t);101===o[0]&&insertEscapedCodePoint(o,0,o[0]);const r=String.fromCodePoint(...o),i="+"===e[4].signCharacter?e[4].signCharacter:"",s=e[4].value.toString();e[1]=`${i}${s}${r}`,e[4].unit=n}function serializeIdent(e){let n;if(0===e[0])e.splice(0,1,s),n=1;else if(e[0]===o&&e[1]===o)n=2;else if(e[0]===o&&e[1])n=2,isIdentStartCodePoint(e[1])||(n+=insertEscapedCodePoint(e,1,e[1]));else{if(e[0]===o&&!e[1])return[92,e[0]];isIdentStartCodePoint(e[0])?n=1:(n=1,n+=insertEscapedCodePoint(e,0,e[0]))}for(let t=n;t<e.length;t++)0!==e[t]?isIdentCodePoint(e[t])||(t+=insertEscapedCharacter(e,t,e[t])):(e.splice(t,1,s),t++);return e}function insertEscapedCharacter(e,n,t){return e.splice(n,1,92,t),1}function insertEscapedCodePoint(e,n,t){const o=t.toString(16),r=[];for(const e of o)r.push(e.codePointAt(0));return e.splice(n,1,92,...r,32),1+r.length}const d=Object.values(c);function isToken(e){return!!Array.isArray(e)&&(!(e.length<4)&&(!!d.includes(e[0])&&("string"==typeof e[1]&&("number"==typeof e[2]&&"number"==typeof e[3]))))}function isTokenNumeric(e){if(!e)return!1;switch(e[0]){case c.Dimension:case c.Number:case c.Percentage:return!0;default:return!1}}function isTokenWhiteSpaceOrComment(e){if(!e)return!1;switch(e[0]){case c.Whitespace:case c.Comment:return!0;default:return!1}}function isTokenAtKeyword(e){return!!e&&e[0]===c.AtKeyword}function isTokenBadString(e){return!!e&&e[0]===c.BadString}function isTokenBadURL(e){return!!e&&e[0]===c.BadURL}function isTokenCDC(e){return!!e&&e[0]===c.CDC}function isTokenCDO(e){return!!e&&e[0]===c.CDO}function isTokenColon(e){return!!e&&e[0]===c.Colon}function isTokenComma(e){return!!e&&e[0]===c.Comma}function isTokenComment(e){return!!e&&e[0]===c.Comment}function isTokenDelim(e){return!!e&&e[0]===c.Delim}function isTokenDimension(e){return!!e&&e[0]===c.Dimension}function isTokenEOF(e){return!!e&&e[0]===c.EOF}function isTokenFunction(e){return!!e&&e[0]===c.Function}function isTokenHash(e){return!!e&&e[0]===c.Hash}function isTokenIdent(e){return!!e&&e[0]===c.Ident}function isTokenNumber(e){return!!e&&e[0]===c.Number}function isTokenPercentage(e){return!!e&&e[0]===c.Percentage}function isTokenSemicolon(e){return!!e&&e[0]===c.Semicolon}function isTokenString(e){return!!e&&e[0]===c.String}function isTokenURL(e){return!!e&&e[0]===c.URL}function isTokenWhitespace(e){return!!e&&e[0]===c.Whitespace}function isTokenOpenParen(e){return!!e&&e[0]===c.OpenParen}function isTokenCloseParen(e){return!!e&&e[0]===c.CloseParen}function isTokenOpenSquare(e){return!!e&&e[0]===c.OpenSquare}function isTokenCloseSquare(e){return!!e&&e[0]===c.CloseSquare}function isTokenOpenCurly(e){return!!e&&e[0]===c.OpenCurly}function isTokenCloseCurly(e){return!!e&&e[0]===c.CloseCurly}function isTokenUnicodeRange(e){return!!e&&e[0]===c.UnicodeRange}export{u as HashType,a as NumberType,ParseError,e as ParseErrorMessage,ParseErrorWithToken,c as TokenType,cloneTokens,isToken,isTokenAtKeyword,isTokenBadString,isTokenBadURL,isTokenCDC,isTokenCDO,isTokenCloseCurly,isTokenCloseParen,isTokenCloseSquare,isTokenColon,isTokenComma,isTokenComment,isTokenDelim,isTokenDimension,isTokenEOF,isTokenFunction,isTokenHash,isTokenIdent,isTokenNumber,isTokenNumeric,isTokenOpenCurly,isTokenOpenParen,isTokenOpenSquare,isTokenPercentage,isTokenSemicolon,isTokenString,isTokenURL,isTokenUnicodeRange,isTokenWhiteSpaceOrComment,isTokenWhitespace,mirrorVariant,mirrorVariantType,mutateIdent,mutateUnit,stringify,tokenize,tokenizer};
diff --git a/packages/css-tokenizer/package.json b/packages/css-tokenizer/package.json
index d56248faf0..4d070ea9ed 100644
--- a/packages/css-tokenizer/package.json
+++ b/packages/css-tokenizer/package.json
@@ -41,7 +41,7 @@
 		"dist"
 	],
 	"devDependencies": {
-		"@rmenke/css-tokenizer-tests": "^1.2.0",
+		"@rmenke/css-tokenizer-tests": "^1.3.1",
 		"postcss": "^8.5.10",
 		"postcss-parser-tests": "^8.10.0"
 	},
diff --git a/packages/css-tokenizer/src/consume/url-token.ts b/packages/css-tokenizer/src/consume/url-token.ts
index 1b3f9599de..eb3efdc8cb 100644
--- a/packages/css-tokenizer/src/consume/url-token.ts
+++ b/packages/css-tokenizer/src/consume/url-token.ts
@@ -169,13 +169,13 @@ export function consumeUrlToken(ctx: Context, reader: CodePointReader): TokenURL
 			return token;
 		}
 
-		if (reader.source.codePointAt(reader.cursor) === NULL || isSurrogate(reader.source.codePointAt(reader.cursor) ?? -1)) {
+		if (codePoint === NULL || isSurrogate(codePoint ?? -1)) {
 			string = string + String.fromCodePoint(REPLACEMENT_CHARACTER);
-			reader.advanceCodePoint();
+			reader.advanceCodePoint(1 + +((codePoint ?? -1) > 0xffff));
 			continue;
 		}
 
-		string = string + reader.source[reader.cursor];
-		reader.advanceCodePoint();
+		string = string + String.fromCodePoint(codePoint ?? -1);
+		reader.advanceCodePoint(1 + +((codePoint ?? -1) > 0xffff));
 	}
 }
diff --git a/packages/css-tokenizer/src/reader.ts b/packages/css-tokenizer/src/reader.ts
index d95b0cbcc2..fd1ce3a9bd 100644
--- a/packages/css-tokenizer/src/reader.ts
+++ b/packages/css-tokenizer/src/reader.ts
@@ -25,7 +25,7 @@ export class Reader implements CodePointReader {
 			return undefined;
 		}
 
-		this.cursor = this.cursor + 1;
+		this.cursor = this.cursor + 1 + +(codePoint > 0xffff);
 		this.representationEnd = this.cursor - 1;
 
 		return codePoint;

From 5f229acbecf9f0c4f9a3580d2b1bdcb9513054cb Mon Sep 17 00:00:00 2001
From: Romain Menke <romainmenke@gmail.com>
Date: Thu, 17 Sep 2026 22:18:35 +0200
Subject: [PATCH 2/2] increase test coverage

---
 packages/css-tokenizer/test/test.mjs          |   4 +
 packages/css-tokenizer/test/token/basic.mjs   |  14 ++
 packages/css-tokenizer/test/token/cdo.mjs     |  33 ++++
 .../css-tokenizer/test/token/is-token.mjs     | 164 +++++++++++++++++-
 packages/css-tokenizer/test/token/numeric.mjs | 128 ++++++++++++++
 .../test/token/unicode-range.mjs              |  14 ++
 packages/css-tokenizer/test/token/url.mjs     |  62 +++++++
 .../css-tokenizer/test/util/clone-tokens.mjs  |  30 ++++
 .../test/util/mirror-variant.mjs              |  35 ++++
 .../test/wpt/cdc-vs-ident-tokens.mjs          |  15 ++
 10 files changed, 498 insertions(+), 1 deletion(-)
 create mode 100644 packages/css-tokenizer/test/util/clone-tokens.mjs
 create mode 100644 packages/css-tokenizer/test/util/mirror-variant.mjs

diff --git a/packages/css-tokenizer/test/test.mjs b/packages/css-tokenizer/test/test.mjs
index 9c5dafb721..6af3898c86 100644
--- a/packages/css-tokenizer/test/test.mjs
+++ b/packages/css-tokenizer/test/test.mjs
@@ -34,6 +34,10 @@ import './wpt/decimal-points-in-numbers.mjs';
 import './wpt/ident-three-code-points.mjs';
 import './wpt/inclusive-ranges.mjs';
 
+// Util
+import './util/clone-tokens.mjs';
+import './util/mirror-variant.mjs';
+
 // Mutations
 import './mutations/ident.mjs';
 import './mutations/dimension.mjs';
diff --git a/packages/css-tokenizer/test/token/basic.mjs b/packages/css-tokenizer/test/token/basic.mjs
index b7c8cbb03d..66b9e675d6 100644
--- a/packages/css-tokenizer/test/token/basic.mjs
+++ b/packages/css-tokenizer/test/token/basic.mjs
@@ -380,6 +380,20 @@ bar") and (fancy(baz))) {}`,
 	);
 }
 
+{
+	const t = tokenizer({
+		css: '-\\',
+	});
+
+	assert.deepEqual(
+		collectTokens(t),
+		[
+			['ident-token', '-\\', 0, 1, { value: '-�' }],
+			['EOF-token', '', -1, -1, undefined],
+		],
+	);
+}
+
 {
 	const t = tokenizer({
 		css: `\\0
diff --git a/packages/css-tokenizer/test/token/cdo.mjs b/packages/css-tokenizer/test/token/cdo.mjs
index b828a04679..65c3249a2c 100644
--- a/packages/css-tokenizer/test/token/cdo.mjs
+++ b/packages/css-tokenizer/test/token/cdo.mjs
@@ -48,3 +48,36 @@ import { collectTokens } from '../util/collect-tokens.mjs';
 		],
 	);
 }
+
+{
+	{
+		const t = tokenizer({
+			css: '<x--',
+		});
+
+		assert.deepEqual(
+			collectTokens(t),
+			[
+				['delim-token', '<', 0, 0, { value: '<' }],
+				['ident-token', 'x--', 1, 3, { value: 'x--' }],
+				['EOF-token', '', -1, -1, undefined],
+			],
+		);
+	}
+
+	{
+		const t = tokenizer({
+			css: '<!x-',
+		});
+
+		assert.deepEqual(
+			collectTokens(t),
+			[
+				['delim-token', '<', 0, 0, { value: '<' }],
+				['delim-token', '!', 1, 1, { value: '!' }],
+				['ident-token', 'x-', 2, 3, { value: 'x-' }],
+				['EOF-token', '', -1, -1, undefined],
+			],
+		);
+	}
+}
diff --git a/packages/css-tokenizer/test/token/is-token.mjs b/packages/css-tokenizer/test/token/is-token.mjs
index e97189c8db..3a9e141136 100644
--- a/packages/css-tokenizer/test/token/is-token.mjs
+++ b/packages/css-tokenizer/test/token/is-token.mjs
@@ -1,5 +1,167 @@
 import assert from 'node:assert';
-import { isToken, NumberType, TokenType } from '@csstools/css-tokenizer';
+import {
+	isToken,
+	isTokenAtKeyword,
+	isTokenBadString,
+	isTokenBadURL,
+	isTokenCDC,
+	isTokenCDO,
+	isTokenCloseCurly,
+	isTokenCloseParen,
+	isTokenCloseSquare,
+	isTokenColon,
+	isTokenComma,
+	isTokenComment,
+	isTokenDelim,
+	isTokenDimension,
+	isTokenEOF,
+	isTokenFunction,
+	isTokenHash,
+	isTokenIdent,
+	isTokenNumber,
+	isTokenNumeric,
+	isTokenOpenCurly,
+	isTokenOpenParen,
+	isTokenOpenSquare,
+	isTokenPercentage,
+	isTokenSemicolon,
+	isTokenString,
+	isTokenURL,
+	isTokenUnicodeRange,
+	isTokenWhitespace,
+	isTokenWhiteSpaceOrComment,
+	NumberType,
+	TokenType,
+} from '@csstools/css-tokenizer';
 
 assert.ok(isToken([TokenType.Number, (3).toString(), -1, -1, { value: 3, type: NumberType.Number }]));
 assert.ok(isToken(['number-token', (3).toString(), -1, -1, { value: 3, type: NumberType.Number }]));
+assert.ok(!isToken(null));
+assert.ok(!isToken(undefined));
+assert.ok(!isToken([TokenType.Number, (3).toString(), -1]));
+assert.ok(!isToken(['not-a-token', (3).toString(), -1, -1, { value: 3 }]));
+
+{
+	const tokenByType = {
+		[TokenType.AtKeyword]: [TokenType.AtKeyword, '@foo', 0, 3, { value: 'foo' }],
+		[TokenType.BadString]: [TokenType.BadString, 'bad-string-token', 0, 3, undefined],
+		[TokenType.BadURL]: [TokenType.BadURL, 'bad-url-token', 0, 3, undefined],
+		[TokenType.CDC]: [TokenType.CDC, '-->', 0, 2, undefined],
+		[TokenType.CDO]: [TokenType.CDO, '<!--', 0, 3, undefined],
+		[TokenType.CloseCurly]: [TokenType.CloseCurly, '}', 0, 0, undefined],
+		[TokenType.CloseParen]: [TokenType.CloseParen, ')', 0, 0, undefined],
+		[TokenType.CloseSquare]: [TokenType.CloseSquare, ']', 0, 0, undefined],
+		[TokenType.Colon]: [TokenType.Colon, ':', 0, 0, undefined],
+		[TokenType.Comma]: [TokenType.Comma, ',', 0, 0, undefined],
+		[TokenType.Comment]: [TokenType.Comment, '/*x*/', 0, 4, undefined],
+		[TokenType.Delim]: [TokenType.Delim, '*', 0, 0, { value: '*' }],
+		[TokenType.Dimension]: [TokenType.Dimension, '3px', 0, 2, { value: 3, unit: 'px', type: NumberType.Integer }],
+		[TokenType.EOF]: [TokenType.EOF, '', -1, -1, undefined],
+		[TokenType.Function]: [TokenType.Function, 'foo(', 0, 3, { value: 'foo' }],
+		[TokenType.Hash]: [TokenType.Hash, '#foo', 0, 3, { value: 'foo', type: 'id' }],
+		[TokenType.Ident]: [TokenType.Ident, 'foo', 0, 2, { value: 'foo' }],
+		[TokenType.Number]: [TokenType.Number, '3', 0, 0, { value: 3, type: NumberType.Integer }],
+		[TokenType.OpenCurly]: [TokenType.OpenCurly, '{', 0, 0, undefined],
+		[TokenType.OpenParen]: [TokenType.OpenParen, '(', 0, 0, undefined],
+		[TokenType.OpenSquare]: [TokenType.OpenSquare, '[', 0, 0, undefined],
+		[TokenType.Percentage]: [TokenType.Percentage, '3%', 0, 1, { value: 3 }],
+		[TokenType.Semicolon]: [TokenType.Semicolon, ';', 0, 0, undefined],
+		[TokenType.String]: [TokenType.String, '"foo"', 0, 4, { value: 'foo' }],
+		[TokenType.URL]: [TokenType.URL, 'url(foo)', 0, 7, { value: 'foo' }],
+		[TokenType.UnicodeRange]: [TokenType.UnicodeRange, 'U+0-7F', 0, 6, { startOfRange: 0, endOfRange: 127 }],
+		[TokenType.Whitespace]: [TokenType.Whitespace, ' ', 0, 0, undefined],
+	};
+
+	const predicates = [
+		isTokenAtKeyword,
+		isTokenBadString,
+		isTokenBadURL,
+		isTokenCDC,
+		isTokenCDO,
+		isTokenCloseCurly,
+		isTokenCloseParen,
+		isTokenCloseSquare,
+		isTokenColon,
+		isTokenComma,
+		isTokenComment,
+		isTokenDelim,
+		isTokenDimension,
+		isTokenEOF,
+		isTokenFunction,
+		isTokenHash,
+		isTokenIdent,
+		isTokenNumber,
+		isTokenOpenCurly,
+		isTokenOpenParen,
+		isTokenOpenSquare,
+		isTokenPercentage,
+		isTokenSemicolon,
+		isTokenString,
+		isTokenURL,
+		isTokenUnicodeRange,
+		isTokenWhitespace,
+	];
+
+	const everyOtherToken = Object.entries(tokenByType).map(([type, token]) => ({ type, token }));
+
+	for (const predicate of predicates) {
+		for (const { type, token } of everyOtherToken) {
+			assert.strictEqual(
+				predicate(token),
+				token[0] === tokenByTypeEntryForPredicate(predicate),
+				`${predicate.name} for ${type}`,
+			);
+		}
+
+		assert.strictEqual(predicate(undefined), false, `${predicate.name} for undefined`);
+		assert.strictEqual(predicate(null), false, `${predicate.name} for null`);
+	}
+}
+
+function tokenByTypeEntryForPredicate(predicate) {
+	switch (predicate) {
+		case isTokenAtKeyword: return TokenType.AtKeyword;
+		case isTokenBadString: return TokenType.BadString;
+		case isTokenBadURL: return TokenType.BadURL;
+		case isTokenCDC: return TokenType.CDC;
+		case isTokenCDO: return TokenType.CDO;
+		case isTokenCloseCurly: return TokenType.CloseCurly;
+		case isTokenCloseParen: return TokenType.CloseParen;
+		case isTokenCloseSquare: return TokenType.CloseSquare;
+		case isTokenColon: return TokenType.Colon;
+		case isTokenComma: return TokenType.Comma;
+		case isTokenComment: return TokenType.Comment;
+		case isTokenDelim: return TokenType.Delim;
+		case isTokenDimension: return TokenType.Dimension;
+		case isTokenEOF: return TokenType.EOF;
+		case isTokenFunction: return TokenType.Function;
+		case isTokenHash: return TokenType.Hash;
+		case isTokenIdent: return TokenType.Ident;
+		case isTokenNumber: return TokenType.Number;
+		case isTokenOpenCurly: return TokenType.OpenCurly;
+		case isTokenOpenParen: return TokenType.OpenParen;
+		case isTokenOpenSquare: return TokenType.OpenSquare;
+		case isTokenPercentage: return TokenType.Percentage;
+		case isTokenSemicolon: return TokenType.Semicolon;
+		case isTokenString: return TokenType.String;
+		case isTokenURL: return TokenType.URL;
+		case isTokenUnicodeRange: return TokenType.UnicodeRange;
+		case isTokenWhitespace: return TokenType.Whitespace;
+		default: throw new Error('unexpected predicate');
+	}
+}
+
+{
+	assert.ok(isTokenNumeric([TokenType.Number, '3', -1, -1, { value: 3, type: NumberType.Integer }]));
+	assert.ok(isTokenNumeric([TokenType.Dimension, '3px', -1, -1, { value: 3, type: NumberType.Integer, unit: 'px' }]));
+	assert.ok(isTokenNumeric([TokenType.Percentage, '3%', -1, -1, { value: 3 }]));
+	assert.ok(!isTokenNumeric([TokenType.Ident, 'foo', -1, -1, { value: 'foo' }]));
+	assert.ok(!isTokenNumeric(undefined));
+}
+
+{
+	assert.ok(isTokenWhiteSpaceOrComment([TokenType.Whitespace, ' ', -1, -1, undefined]));
+	assert.ok(isTokenWhiteSpaceOrComment([TokenType.Comment, '/*x*/', -1, -1, undefined]));
+	assert.ok(!isTokenWhiteSpaceOrComment([TokenType.Ident, 'foo', -1, -1, { value: 'foo' }]));
+	assert.ok(!isTokenWhiteSpaceOrComment(undefined));
+}
diff --git a/packages/css-tokenizer/test/token/numeric.mjs b/packages/css-tokenizer/test/token/numeric.mjs
index f04c989e6b..15d5e06434 100644
--- a/packages/css-tokenizer/test/token/numeric.mjs
+++ b/packages/css-tokenizer/test/token/numeric.mjs
@@ -530,3 +530,131 @@ import { collectTokens } from '../util/collect-tokens.mjs';
 		],
 	);
 }
+
+{
+	const t = tokenizer({
+		css: '+.',
+	});
+
+	assert.deepEqual(
+		collectTokens(t).slice(0, -1),
+		[
+			['delim-token', '+', 0, 0, { value: '+' }],
+			['delim-token', '.', 1, 1, { value: '.' }],
+		],
+	);
+}
+
+{
+	const t = tokenizer({
+		css: '..5',
+	});
+
+	assert.deepEqual(
+		collectTokens(t).slice(0, -1),
+		[
+			['delim-token', '.', 0, 0, { value: '.' }],
+			['number-token', '.5', 1, 2, { value: 0.5, signCharacter: undefined, type: 'number' }],
+		],
+	);
+}
+
+{
+	{
+		const t = tokenizer({
+			css: '1e',
+		});
+
+		assert.deepEqual(
+			collectTokens(t).slice(0, -1),
+			[
+				[
+					'dimension-token',
+					'1e',
+					0,
+					1,
+					{ value: 1, signCharacter: undefined, type: 'integer', unit: 'e' },
+				],
+			],
+		);
+	}
+
+	{
+		const t = tokenizer({
+			css: '1e+',
+		});
+
+		assert.deepEqual(
+			collectTokens(t).slice(0, -1),
+			[
+				[
+					'dimension-token',
+					'1e',
+					0,
+					1,
+					{ value: 1, signCharacter: undefined, type: 'integer', unit: 'e' },
+				],
+				['delim-token', '+', 2, 2, { value: '+' }],
+			],
+		);
+	}
+
+	{
+		const t = tokenizer({
+			css: '1e-',
+		});
+
+		assert.deepEqual(
+			collectTokens(t).slice(0, -1),
+			[
+				[
+					'dimension-token',
+					'1e-',
+					0,
+					2,
+					{ value: 1, signCharacter: undefined, type: 'integer', unit: 'e-' },
+				],
+			],
+		);
+	}
+}
+
+{
+	{
+		const t = tokenizer({
+			css: '1e5',
+		});
+
+		assert.deepEqual(
+			collectTokens(t).slice(0, -1),
+			[
+				[
+					'number-token',
+					'1e5',
+					0,
+					2,
+					{ value: 100000, signCharacter: undefined, type: 'number' },
+				],
+			],
+		);
+	}
+
+	{
+		const t = tokenizer({
+			css: '1e55',
+		});
+
+		assert.deepEqual(
+			collectTokens(t).slice(0, -1),
+			[
+				[
+					'number-token',
+					'1e55',
+					0,
+					3,
+					{ value: 1e55, signCharacter: undefined, type: 'number' },
+				],
+			],
+		);
+	}
+}
diff --git a/packages/css-tokenizer/test/token/unicode-range.mjs b/packages/css-tokenizer/test/token/unicode-range.mjs
index f0e9791c39..75c04bf144 100644
--- a/packages/css-tokenizer/test/token/unicode-range.mjs
+++ b/packages/css-tokenizer/test/token/unicode-range.mjs
@@ -146,6 +146,20 @@ import { collectTokens } from '../util/collect-tokens.mjs';
 		],
 	);
 }
+{
+	const t = tokenizer({
+		css: 'u+',
+		unicodeRangesAllowed: true,
+	});
+
+	assert.deepEqual(
+		collectTokens(t).slice(0, -1),
+		[
+			['ident-token', 'u', 0, 0, { value: 'u' }],
+			['delim-token', '+', 1, 1, { value: '+' }],
+		],
+	);
+}
 
 {
 	const t = tokenizer({
diff --git a/packages/css-tokenizer/test/token/url.mjs b/packages/css-tokenizer/test/token/url.mjs
index 89f1c143ab..58e6004539 100644
--- a/packages/css-tokenizer/test/token/url.mjs
+++ b/packages/css-tokenizer/test/token/url.mjs
@@ -436,3 +436,65 @@ url( 'mix-quoted" ' )\
 		],
 	);
 }
+
+{
+	{
+		const t = tokenizer({
+			css: 'urlx(foo)',
+		});
+
+		assert.deepEqual(
+			collectTokens(t),
+			[
+				['function-token', 'urlx(', 0, 4, { value: 'urlx' }],
+				['ident-token', 'foo', 5, 7, { value: 'foo' }],
+				[')-token', ')', 8, 8, undefined],
+				['EOF-token', '', -1, -1, undefined],
+			],
+		);
+	}
+
+	{
+		const t = tokenizer({
+			css: 'xrl(foo)',
+		});
+
+		assert.deepEqual(
+			collectTokens(t),
+			[
+				['function-token', 'xrl(', 0, 3, { value: 'xrl' }],
+				['ident-token', 'foo', 4, 6, { value: 'foo' }],
+				[')-token', ')', 7, 7, undefined],
+				['EOF-token', '', -1, -1, undefined],
+			],
+		);
+	}
+}
+
+{
+	const t = tokenizer({
+		css: 'url(a\ud800b)',
+	});
+
+	assert.deepEqual(
+		collectTokens(t),
+		[
+			['url-token', 'url(a\ud800b)', 0, 7, { value: 'a�b' }],
+			['EOF-token', '', -1, -1, undefined],
+		],
+	);
+}
+
+{
+	const t = tokenizer({
+		css: 'url(foo  ',
+	});
+
+	assert.deepEqual(
+		collectTokens(t),
+		[
+			['url-token', 'url(foo  ', 0, 8, { value: 'foo' }],
+			['EOF-token', '', -1, -1, undefined],
+		],
+	);
+}
diff --git a/packages/css-tokenizer/test/util/clone-tokens.mjs b/packages/css-tokenizer/test/util/clone-tokens.mjs
new file mode 100644
index 0000000000..4e49fed6ba
--- /dev/null
+++ b/packages/css-tokenizer/test/util/clone-tokens.mjs
@@ -0,0 +1,30 @@
+import assert from 'node:assert';
+import { cloneTokens, TokenType } from '@csstools/css-tokenizer';
+
+{
+	const tokens = [
+		[TokenType.Ident, 'foo', 0, 2, { value: 'foo' }],
+		[TokenType.Dimension, '3px', 3, 5, { value: 3, unit: 'px', type: 'integer' }],
+		[TokenType.EOF, '', -1, -1, undefined],
+	];
+
+	const clone = cloneTokens(tokens);
+
+	assert.deepEqual(clone, tokens);
+	assert.notStrictEqual(clone, tokens);
+	assert.notStrictEqual(clone[0], tokens[0]);
+	assert.notStrictEqual(clone[0][4], tokens[0][4]);
+
+	// mutating the clone must not affect the original
+	clone[0][1] = 'bar';
+	clone[0][4].value = 'bar';
+
+	assert.deepEqual(
+		tokens,
+		[
+			[TokenType.Ident, 'foo', 0, 2, { value: 'foo' }],
+			[TokenType.Dimension, '3px', 3, 5, { value: 3, unit: 'px', type: 'integer' }],
+			[TokenType.EOF, '', -1, -1, undefined],
+		],
+	);
+}
diff --git a/packages/css-tokenizer/test/util/mirror-variant.mjs b/packages/css-tokenizer/test/util/mirror-variant.mjs
new file mode 100644
index 0000000000..969442a09e
--- /dev/null
+++ b/packages/css-tokenizer/test/util/mirror-variant.mjs
@@ -0,0 +1,35 @@
+import assert from 'node:assert';
+import { mirrorVariant, mirrorVariantType, TokenType } from '@csstools/css-tokenizer';
+
+{
+	{
+		assert.strictEqual(mirrorVariantType(TokenType.OpenParen), TokenType.CloseParen);
+		assert.strictEqual(mirrorVariantType(TokenType.CloseParen), TokenType.OpenParen);
+		assert.strictEqual(mirrorVariantType(TokenType.OpenCurly), TokenType.CloseCurly);
+		assert.strictEqual(mirrorVariantType(TokenType.CloseCurly), TokenType.OpenCurly);
+		assert.strictEqual(mirrorVariantType(TokenType.OpenSquare), TokenType.CloseSquare);
+		assert.strictEqual(mirrorVariantType(TokenType.CloseSquare), TokenType.OpenSquare);
+	}
+
+	{
+		assert.strictEqual(mirrorVariantType(TokenType.Ident), null);
+		assert.strictEqual(mirrorVariantType(TokenType.Number), null);
+		assert.strictEqual(mirrorVariantType(TokenType.EOF), null);
+	}
+}
+
+{
+	{
+		assert.deepEqual(mirrorVariant([TokenType.OpenParen, '(', 0, 0, undefined]), [TokenType.CloseParen, ')', -1, -1, undefined]);
+		assert.deepEqual(mirrorVariant([TokenType.CloseParen, ')', 0, 0, undefined]), [TokenType.OpenParen, '(', -1, -1, undefined]);
+		assert.deepEqual(mirrorVariant([TokenType.OpenCurly, '{', 0, 0, undefined]), [TokenType.CloseCurly, '}', -1, -1, undefined]);
+		assert.deepEqual(mirrorVariant([TokenType.CloseCurly, '}', 0, 0, undefined]), [TokenType.OpenCurly, '{', -1, -1, undefined]);
+		assert.deepEqual(mirrorVariant([TokenType.OpenSquare, '[', 0, 0, undefined]), [TokenType.CloseSquare, ']', -1, -1, undefined]);
+		assert.deepEqual(mirrorVariant([TokenType.CloseSquare, ']', 0, 0, undefined]), [TokenType.OpenSquare, '[', -1, -1, undefined]);
+	}
+
+	{
+		assert.strictEqual(mirrorVariant([TokenType.Ident, 'foo', 0, 2, { value: 'foo' }]), null);
+		assert.strictEqual(mirrorVariant([TokenType.EOF, '', -1, -1, undefined]), null);
+	}
+}
diff --git a/packages/css-tokenizer/test/wpt/cdc-vs-ident-tokens.mjs b/packages/css-tokenizer/test/wpt/cdc-vs-ident-tokens.mjs
index 5ef0acf77c..38a3f8db7a 100644
--- a/packages/css-tokenizer/test/wpt/cdc-vs-ident-tokens.mjs
+++ b/packages/css-tokenizer/test/wpt/cdc-vs-ident-tokens.mjs
@@ -26,3 +26,18 @@ import { collectTokens } from '../util/collect-tokens.mjs';
 		],
 	);
 }
+
+{
+	const t = tokenizer({
+		css: '-x>',
+	});
+
+	assert.deepEqual(
+		collectTokens(t),
+		[
+			['ident-token', '-x', 0, 1, { value: '-x' }],
+			['delim-token', '>', 2, 2, { value: '>' }],
+			['EOF-token', '', -1, -1, undefined],
+		],
+	);
+}