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Merged
merged 1 commit into from
Jul 19, 2019
Merged

Add minimal support of CSS custom properties #250

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1 change: 1 addition & 0 deletions .jshintrc
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Original file line number Diff line number Diff line change
Expand Up @@ -2,6 +2,7 @@
"bitwise": true,
"curly": true,
"eqeqeq": true,
"eqnull": true,
"evil": true,
"forin": true,
"freeze": true,
Expand Down
29 changes: 21 additions & 8 deletions src/css/Parser.js
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Original file line number Diff line number Diff line change
Expand Up @@ -1077,10 +1077,10 @@ Parser.prototype = function() {
* ;
*/

var tokenStream = this._tokenStream,
value = null,
hack = null,
tokenValue,
var tokenStream = this._tokenStream,
value = null,
hack = null,
propertyName = "",
token,
line,
col;
Expand All @@ -1094,18 +1094,31 @@ Parser.prototype = function() {
col = token.startCol;
}

// consume a single hyphen before finding the identifier, to support custom properties
if (tokenStream.peek() === Tokens.MINUS) {
tokenStream.get();
token = tokenStream.token();
propertyName = token.value;
line = token.startLine;
col = token.startCol;
}

if (tokenStream.match(Tokens.IDENT)) {
token = tokenStream.token();
tokenValue = token.value;
propertyName += token.value;

// check for underscore hack - no error if not allowed because it's valid CSS syntax
if (tokenValue.charAt(0) === "_" && this.options.underscoreHack) {
if (propertyName.charAt(0) === "_" && this.options.underscoreHack) {
hack = "_";
tokenValue = tokenValue.substring(1);
propertyName = propertyName.substring(1);
}

value = new PropertyName(tokenValue, hack, line || token.startLine, col || token.startCol);
value = new PropertyName(propertyName, hack, line || token.startLine, col || token.startCol);
this._readWhitespace();
} else if (tokenStream.peek() === Tokens.RBRACE) {
// Encountered when there are no more properties.
} else {
this._unexpectedToken(tokenStream.LT(1));
}

return value;
Expand Down
145 changes: 93 additions & 52 deletions src/css/TokenStream.js
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Original file line number Diff line number Diff line change
Expand Up @@ -18,31 +18,31 @@ var h = /^[0-9a-fA-F]$/,


function isHexDigit(c) {
return c !== null && h.test(c);
return c != null && h.test(c);
}

function isDigit(c) {
return c !== null && /\d/.test(c);
return c != null && /\d/.test(c);
}

function isWhitespace(c) {
return c !== null && whitespace.test(c);
return c != null && whitespace.test(c);
}

function isNewLine(c) {
return c !== null && nl.test(c);
return c != null && nl.test(c);
}

function isNameStart(c) {
return c !== null && /[a-z_\u00A0-\uFFFF\\]/i.test(c);
return c != null && /[a-z_\u00A0-\uFFFF\\]/i.test(c);
}

function isNameChar(c) {
return c !== null && (isNameStart(c) || /[0-9\-\\]/.test(c));
return c != null && (isNameStart(c) || /[0-9\-\\]/.test(c));
}

function isIdentStart(c) {
return c !== null && (isNameStart(c) || /-\\/.test(c));
return c != null && (isNameStart(c) || /-\\/.test(c));
}

function mix(receiver, supplier) {
Expand All @@ -54,6 +54,16 @@ function mix(receiver, supplier) {
return receiver;
}

function wouldStartIdent(twoCodePoints) {
return typeof twoCodePoints === "string" &&
(twoCodePoints[0] === "-" && isNameStart(twoCodePoints[1]) || isNameStart(twoCodePoints[0]));
}

function wouldStartUnsignedNumber(twoCodePoints) {
return typeof twoCodePoints === "string" &&
(isDigit(twoCodePoints[0]) || (twoCodePoints[0] === "." && isDigit(twoCodePoints[1])));
}

//-----------------------------------------------------------------------------
// CSS Token Stream
//-----------------------------------------------------------------------------
Expand Down Expand Up @@ -89,7 +99,6 @@ TokenStream.prototype = mix(new TokenStreamBase(), {

c = reader.read();


while (c) {
switch (c) {

Expand Down Expand Up @@ -170,16 +179,31 @@ TokenStream.prototype = mix(new TokenStreamBase(), {
/*
* Potential tokens:
* - CDC
* - MINUS
* - NUMBER
* - DIMENSION
* - PERCENTAGE
* - IDENT
* - MINUS
*/
case "-":
if (reader.peek() === "-") { // could be closing HTML-style comment
if (wouldStartUnsignedNumber(reader.peekCount(2))) {
token = this.numberToken(c, startLine, startCol);
break;
} else if (reader.peekCount(2) === "->") {
token = this.htmlCommentEndToken(c, startLine, startCol);
} else if (isNameStart(reader.peek())) {
token = this.identOrFunctionToken(c, startLine, startCol);
} else {
token = this._getDefaultToken(c, startLine, startCol);
}
break;

/*
* Potential tokens:
* - NUMBER
* - PLUS
*/
case "+":
if (wouldStartUnsignedNumber(reader.peekCount(2))) {
token = this.numberToken(c, startLine, startCol);
} else {
token = this.charToken(c, startLine, startCol);
}
Expand Down Expand Up @@ -242,48 +266,13 @@ TokenStream.prototype = mix(new TokenStreamBase(), {
case "u":
if (reader.peek() === "+") {
token = this.unicodeRangeToken(c, startLine, startCol);
break;
}
/* falls through */
default:

/*
* Potential tokens:
* - NUMBER
* - DIMENSION
* - LENGTH
* - FREQ
* - TIME
* - EMS
* - EXS
* - ANGLE
*/
if (isDigit(c)) {
token = this.numberToken(c, startLine, startCol);
} else

/*
* Potential tokens:
* - S
*/
if (isWhitespace(c)) {
token = this.whitespaceToken(c, startLine, startCol);
} else

/*
* Potential tokens:
* - IDENT
*/
if (isIdentStart(c)) {
token = this.identOrFunctionToken(c, startLine, startCol);
} else {
/*
* Potential tokens:
* - CHAR
* - PLUS
*/
token = this.charToken(c, startLine, startCol);
token = this._getDefaultToken(c, startLine, startCol);
}
break;

default:
token = this._getDefaultToken(c, startLine, startCol);

}

Expand All @@ -299,6 +288,58 @@ TokenStream.prototype = mix(new TokenStreamBase(), {
return token;
},

/**
* Produces a token based on the given character and location in the
* stream, when no other case applies.
* Potential tokens:
* - NUMBER
* - DIMENSION
* - LENGTH
* - FREQ
* - TIME
* - EMS
* - EXS
* - ANGLE
* @param {String} c The character for the token.
* @param {int} startLine The beginning line for the character.
* @param {int} startCol The beginning column for the character.
* @return {Object} A token object.
* @method _getDefaultToken
*/
_getDefaultToken: function(c, startLine, startCol) {
var reader = this._reader,
token = null;

if (isDigit(c)) {
token = this.numberToken(c, startLine, startCol);
} else

/*
* Potential tokens:
* - S
*/
if (isWhitespace(c)) {
token = this.whitespaceToken(c, startLine, startCol);
} else

/*
* Potential tokens:
* - IDENT
*/
if (wouldStartIdent(c + reader.peekCount(1))) {
token = this.identOrFunctionToken(c, startLine, startCol);
} else {
/*
* Potential tokens:
* - CHAR
* - PLUS
*/
token = this.charToken(c, startLine, startCol);
}

return token;
},

//-------------------------------------------------------------------------
// Methods to create tokens
//-------------------------------------------------------------------------
Expand Down
12 changes: 12 additions & 0 deletions src/util/StringReader.js
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Original file line number Diff line number Diff line change
Expand Up @@ -164,6 +164,18 @@ StringReader.prototype = {
// Advanced reading
//-------------------------------------------------------------------------

/**
* Reads a given number of characters without advancing the cursor.
* @param {int} count How many characters to look ahead (default is 1).
* @return {String} The characters as a string, or an empty string if
* there is no next character.
* @method peek
*/
peekCount: function(count) {
count = typeof count === "undefined" ? 1 : Math.max(count, 0);
return this._input.substring(this._cursor, this._cursor + count);
},

/**
* Reads up to and including the given string. Throws an error if that
* string is not found.
Expand Down
43 changes: 42 additions & 1 deletion tests/css/Parser.js
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Original file line number Diff line number Diff line change
Expand Up @@ -2138,6 +2138,21 @@ var YUITest = require("yuitest"),
parser.parse(".foo {\n color: #fff;\n}");
},

"Test rule with custom property": function() {
var parser = new Parser({ strict: true });
parser.addListener("property", function(event) {
Assert.areEqual("--color-Foo_BAR", event.property.toString());
Assert.areEqual("#fff", event.value.toString());
Assert.areEqual(3, event.property.col, "Property column should be 3.");
Assert.areEqual(2, event.property.line, "Property line should be 2.");
Assert.areEqual(3, event.col, "Event column should be 3.");
Assert.areEqual(2, event.line, "Event line should be 2.");
Assert.areEqual(20, event.value.parts[0].col, "First part column should be 20.");
Assert.areEqual(2, event.value.parts[0].line, "First part line should be 2.");
});
parser.parse(".foo {\n --color-Foo_BAR: #fff;\n}");
},

"Test rule with star hack property": function() {
var parser = new Parser({
strict: true,
Expand Down Expand Up @@ -2289,7 +2304,33 @@ var YUITest = require("yuitest"),

name: "Invalid CSS Parsing Tests",

"Test parsing invalid celector": function() {
"Test parsing custom property typo": function() {
var error;
var parser = new Parser();
parser.addListener("error", function(e) {
error = e;
});
parser.parse("a:hover{\ncolor:red;\n==myFont:Helvetica;/*dropped*/;\nborder:0\n}");

Assert.areEqual("error", error.type);
Assert.areEqual(3, error.line);
Assert.areEqual(1, error.col);
},

"Test parsing invalid property": function() {
var error;
var parser = new Parser();
parser.addListener("error", function(e) {
error = e;
});
parser.parse("a:hover{\ncolor:red;\nfont::Helvetica;/*dropped*/;\nborder:0\n}");

Assert.areEqual("error", error.type);
Assert.areEqual(3, error.line);
Assert.areEqual(6, error.col);
},

"Test parsing invalid selector": function() {
var error;
var parser = new Parser();
parser.addListener("error", function(e) {
Expand Down
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