src/third_party/WebKit/Source/devtools/front_end/script_formatter_worker/CSSFormatter.js

   1 /*
   2  * Copyright (C) 2013 Google Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are
   6  * met:
   7  *
   8  *     * Redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer.
  10  *     * Redistributions in binary form must reproduce the above
  11  * copyright notice, this list of conditions and the following disclaimer
  12  * in the documentation and/or other materials provided with the
  13  * distribution.
  14  *     * Neither the name of Google Inc. nor the names of its
  15  * contributors may be used to endorse or promote products derived from
  16  * this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 /**
  32  * @constructor
  33  * @param {string} content
  34  * @param {!FormatterWorker.CSSFormattedContentBuilder} builder
  35  */
  36 FormatterWorker.CSSFormatter = function(content, builder)
  37 {
  38     this._content = content;
  39     this._builder = builder;
  40     this._lastLine = -1;
  41     this._state = {};
  42 }
  43
  44 FormatterWorker.CSSFormatter.prototype = {
  45     format: function()
  46     {
  47         this._lineEndings = this._lineEndings(this._content);
  48         var tokenize = FormatterWorker.createTokenizer("text/css");
  49         var lines = this._content.split("\n");
  50
  51         for (var i = 0; i < lines.length; ++i) {
  52             var line = lines[i];
  53             tokenize(line, this._tokenCallback.bind(this, i));
  54         }
  55         this._builder.flushNewLines(true);
  56     },
  57
  58     /**
  59      * @param {string} text
  60      */
  61     _lineEndings: function(text)
  62     {
  63         var lineEndings = [];
  64         var i = text.indexOf("\n");
  65         while (i !== -1) {
  66             lineEndings.push(i);
  67             i = text.indexOf("\n", i + 1);
  68         }
  69         lineEndings.push(text.length);
  70         return lineEndings;
  71     },
  72
  73     /**
  74      * @param {number} startLine
  75      * @param {string} token
  76      * @param {?string} type
  77      * @param {number} startColumn
  78      */
  79     _tokenCallback: function(startLine, token, type, startColumn)
  80     {
  81         if (startLine !== this._lastLine)
  82             this._state.eatWhitespace = true;
  83         if (/^property/.test(type) && !this._state.inPropertyValue)
  84             this._state.seenProperty = true;
  85         this._lastLine = startLine;
  86         var isWhitespace = /^\s+$/.test(token);
  87         if (isWhitespace) {
  88             if (!this._state.eatWhitespace)
  89                 this._builder.addSpace();
  90             return;
  91         }
  92         this._state.eatWhitespace = false;
  93         if (token === "\n")
  94             return;
  95
  96         if (token !== "}") {
  97             if (this._state.afterClosingBrace)
  98                 this._builder.addNewLine();
  99             this._state.afterClosingBrace = false;
 100         }
 101         var startPosition = (startLine ? this._lineEndings[startLine - 1] : 0) + startColumn;
 102         if (token === "}") {
 103             if (this._state.inPropertyValue)
 104                 this._builder.addNewLine();
 105             this._builder.decreaseNestingLevel();
 106             this._state.afterClosingBrace = true;
 107             this._state.inPropertyValue = false;
 108         } else if (token === ":" && !this._state.inPropertyValue && this._state.seenProperty) {
 109             this._builder.addToken(token, startPosition, startLine, startColumn);
 110             this._builder.addSpace();
 111             this._state.eatWhitespace = true;
 112             this._state.inPropertyValue = true;
 113             this._state.seenProperty = false;
 114             return;
 115         } else if (token === "{") {
 116             this._builder.addSpace();
 117             this._builder.addToken(token, startPosition, startLine, startColumn);
 118             this._builder.addNewLine();
 119             this._builder.increaseNestingLevel();
 120             return;
 121         }
 122
 123         this._builder.addToken(token, startPosition, startLine, startColumn);
 124
 125         if (type === "comment" && !this._state.inPropertyValue && !this._state.seenProperty)
 126             this._builder.addNewLine();
 127         if (token === ";" && this._state.inPropertyValue) {
 128             this._state.inPropertyValue = false;
 129             this._builder.addNewLine();
 130         } else if (token === "}") {
 131             this._builder.addNewLine();
 132         }
 133     }
 134 }
 135
 136 /**
 137  * @constructor
 138  * @param {string} content
 139  * @param {!{original: !Array.<number>, formatted: !Array.<number>}} mapping
 140  * @param {number} originalOffset
 141  * @param {number} formattedOffset
 142  * @param {string} indentString
 143  */
 144 FormatterWorker.CSSFormattedContentBuilder = function(content, mapping, originalOffset, formattedOffset, indentString)
 145 {
 146     this._originalContent = content;
 147     this._originalOffset = originalOffset;
 148     this._lastOriginalPosition = 0;
 149
 150     this._formattedContent = [];
 151     this._formattedContentLength = 0;
 152     this._formattedOffset = formattedOffset;
 153     this._lastFormattedPosition = 0;
 154
 155     this._mapping = mapping;
 156
 157     this._lineNumber = 0;
 158     this._nestingLevel = 0;
 159     this._needNewLines = 0;
 160     this._atLineStart = true;
 161     this._indentString = indentString;
 162     this._cachedIndents = {};
 163 }
 164
 165 FormatterWorker.CSSFormattedContentBuilder.prototype = {
 166     /**
 167      * @param {string} token
 168      * @param {number} startPosition
 169      * @param {number} startLine
 170      * @param {number} startColumn
 171      */
 172     addToken: function(token, startPosition, startLine, startColumn)
 173     {
 174         if ((this._isWhitespaceRun || this._atLineStart) && /^\s+$/.test(token))
 175             return;
 176
 177         if (this._isWhitespaceRun && this._lineNumber === startLine && !this._needNewLines)
 178             this._addText(" ");
 179
 180         this._isWhitespaceRun = false;
 181         this._atLineStart = false;
 182
 183         while (this._lineNumber < startLine) {
 184             this._addText("\n");
 185             this._addIndent();
 186             this._needNewLines = 0;
 187             this._lineNumber += 1;
 188             this._atLineStart = true;
 189         }
 190
 191         if (this._needNewLines) {
 192             this.flushNewLines();
 193             this._addIndent();
 194             this._atLineStart = true;
 195         }
 196
 197         this._addMappingIfNeeded(startPosition);
 198         this._addText(token);
 199         this._lineNumber = startLine;
 200     },
 201
 202     addSpace: function()
 203     {
 204         if (this._isWhitespaceRun)
 205             return;
 206         this._isWhitespaceRun = true;
 207     },
 208
 209     addNewLine: function()
 210     {
 211         ++this._needNewLines;
 212     },
 213
 214     /**
 215      * @param {boolean=} atLeastOne
 216      */
 217     flushNewLines: function(atLeastOne)
 218     {
 219         var newLineCount = atLeastOne && !this._needNewLines ? 1 : this._needNewLines;
 220         if (newLineCount)
 221             this._isWhitespaceRun = false;
 222         for (var i = 0; i < newLineCount; ++i)
 223             this._addText("\n");
 224         this._needNewLines = 0;
 225     },
 226
 227     increaseNestingLevel: function()
 228     {
 229         this._nestingLevel += 1;
 230     },
 231
 232     /**
 233      * @param {boolean=} addNewline
 234      */
 235     decreaseNestingLevel: function(addNewline)
 236     {
 237         if (this._nestingLevel)
 238             this._nestingLevel -= 1;
 239         if (addNewline)
 240             this.addNewLine();
 241     },
 242
 243     /**
 244      * @return {string}
 245      */
 246     content: function()
 247     {
 248         return this._formattedContent.join("");
 249     },
 250
 251     _addIndent: function()
 252     {
 253         if (this._cachedIndents[this._nestingLevel]) {
 254             this._addText(this._cachedIndents[this._nestingLevel]);
 255             return;
 256         }
 257
 258         var fullIndent = "";
 259         for (var i = 0; i < this._nestingLevel; ++i)
 260             fullIndent += this._indentString;
 261         this._addText(fullIndent);
 262
 263         // Cache a maximum of 20 nesting level indents.
 264         if (this._nestingLevel <= 20)
 265             this._cachedIndents[this._nestingLevel] = fullIndent;
 266     },
 267
 268     /**
 269      * @param {string} text
 270      */
 271     _addText: function(text)
 272     {
 273         if (!text)
 274             return;
 275         this._formattedContent.push(text);
 276         this._formattedContentLength += text.length;
 277     },
 278
 279     /**
 280      * @param {number} originalPosition
 281      */
 282     _addMappingIfNeeded: function(originalPosition)
 283     {
 284         if (originalPosition - this._lastOriginalPosition === this._formattedContentLength - this._lastFormattedPosition)
 285             return;
 286         this._mapping.original.push(this._originalOffset + originalPosition);
 287         this._lastOriginalPosition = originalPosition;
 288         this._mapping.formatted.push(this._formattedOffset + this._formattedContentLength);
 289         this._lastFormattedPosition = this._formattedContentLength;
 290     }
 291 }