build: Add some required modules for node

1 files changed, 1082 insertions, 0 deletions

diff --git a/node_modules/source-map/lib/source-map-consumer.js b/node_modules/source-map/lib/source-map-consumer.js
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+++ b/node_modules/source-map/lib/source-map-consumer.js
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+/* -*- Mode: js; js-indent-level: 2; -*- */
+/*
+ * Copyright 2011 Mozilla Foundation and contributors
+ * Licensed under the New BSD license. See LICENSE or:
+ * http://opensource.org/licenses/BSD-3-Clause
+ */
+
+var util = require('./util');
+var binarySearch = require('./binary-search');
+var ArraySet = require('./array-set').ArraySet;
+var base64VLQ = require('./base64-vlq');
+var quickSort = require('./quick-sort').quickSort;
+
+function SourceMapConsumer(aSourceMap) {
+  var sourceMap = aSourceMap;
+  if (typeof aSourceMap === 'string') {
+    sourceMap = JSON.parse(aSourceMap.replace(/^\)\]\}'/, ''));
+  }
+
+  return sourceMap.sections != null
+    ? new IndexedSourceMapConsumer(sourceMap)
+    : new BasicSourceMapConsumer(sourceMap);
+}
+
+SourceMapConsumer.fromSourceMap = function(aSourceMap) {
+  return BasicSourceMapConsumer.fromSourceMap(aSourceMap);
+}
+
+/**
+ * The version of the source mapping spec that we are consuming.
+ */
+SourceMapConsumer.prototype._version = 3;
+
+// `__generatedMappings` and `__originalMappings` are arrays that hold the
+// parsed mapping coordinates from the source map's "mappings" attribute. They
+// are lazily instantiated, accessed via the `_generatedMappings` and
+// `_originalMappings` getters respectively, and we only parse the mappings
+// and create these arrays once queried for a source location. We jump through
+// these hoops because there can be many thousands of mappings, and parsing
+// them is expensive, so we only want to do it if we must.
+//
+// Each object in the arrays is of the form:
+//
+//     {
+//       generatedLine: The line number in the generated code,
+//       generatedColumn: The column number in the generated code,
+//       source: The path to the original source file that generated this
+//               chunk of code,
+//       originalLine: The line number in the original source that
+//                     corresponds to this chunk of generated code,
+//       originalColumn: The column number in the original source that
+//                       corresponds to this chunk of generated code,
+//       name: The name of the original symbol which generated this chunk of
+//             code.
+//     }
+//
+// All properties except for `generatedLine` and `generatedColumn` can be
+// `null`.
+//
+// `_generatedMappings` is ordered by the generated positions.
+//
+// `_originalMappings` is ordered by the original positions.
+
+SourceMapConsumer.prototype.__generatedMappings = null;
+Object.defineProperty(SourceMapConsumer.prototype, '_generatedMappings', {
+  get: function () {
+    if (!this.__generatedMappings) {
+      this._parseMappings(this._mappings, this.sourceRoot);
+    }
+
+    return this.__generatedMappings;
+  }
+});
+
+SourceMapConsumer.prototype.__originalMappings = null;
+Object.defineProperty(SourceMapConsumer.prototype, '_originalMappings', {
+  get: function () {
+    if (!this.__originalMappings) {
+      this._parseMappings(this._mappings, this.sourceRoot);
+    }
+
+    return this.__originalMappings;
+  }
+});
+
+SourceMapConsumer.prototype._charIsMappingSeparator =
+  function SourceMapConsumer_charIsMappingSeparator(aStr, index) {
+    var c = aStr.charAt(index);
+    return c === ";" || c === ",";
+  };
+
+/**
+ * Parse the mappings in a string in to a data structure which we can easily
+ * query (the ordered arrays in the `this.__generatedMappings` and
+ * `this.__originalMappings` properties).
+ */
+SourceMapConsumer.prototype._parseMappings =
+  function SourceMapConsumer_parseMappings(aStr, aSourceRoot) {
+    throw new Error("Subclasses must implement _parseMappings");
+  };
+
+SourceMapConsumer.GENERATED_ORDER = 1;
+SourceMapConsumer.ORIGINAL_ORDER = 2;
+
+SourceMapConsumer.GREATEST_LOWER_BOUND = 1;
+SourceMapConsumer.LEAST_UPPER_BOUND = 2;
+
+/**
+ * Iterate over each mapping between an original source/line/column and a
+ * generated line/column in this source map.
+ *
+ * @param Function aCallback
+ *        The function that is called with each mapping.
+ * @param Object aContext
+ *        Optional. If specified, this object will be the value of `this` every
+ *        time that `aCallback` is called.
+ * @param aOrder
+ *        Either `SourceMapConsumer.GENERATED_ORDER` or
+ *        `SourceMapConsumer.ORIGINAL_ORDER`. Specifies whether you want to
+ *        iterate over the mappings sorted by the generated file's line/column
+ *        order or the original's source/line/column order, respectively. Defaults to
+ *        `SourceMapConsumer.GENERATED_ORDER`.
+ */
+SourceMapConsumer.prototype.eachMapping =
+  function SourceMapConsumer_eachMapping(aCallback, aContext, aOrder) {
+    var context = aContext || null;
+    var order = aOrder || SourceMapConsumer.GENERATED_ORDER;
+
+    var mappings;
+    switch (order) {
+    case SourceMapConsumer.GENERATED_ORDER:
+      mappings = this._generatedMappings;
+      break;
+    case SourceMapConsumer.ORIGINAL_ORDER:
+      mappings = this._originalMappings;
+      break;
+    default:
+      throw new Error("Unknown order of iteration.");
+    }
+
+    var sourceRoot = this.sourceRoot;
+    mappings.map(function (mapping) {
+      var source = mapping.source === null ? null : this._sources.at(mapping.source);
+      if (source != null && sourceRoot != null) {
+        source = util.join(sourceRoot, source);
+      }
+      return {
+        source: source,
+        generatedLine: mapping.generatedLine,
+        generatedColumn: mapping.generatedColumn,
+        originalLine: mapping.originalLine,
+        originalColumn: mapping.originalColumn,
+        name: mapping.name === null ? null : this._names.at(mapping.name)
+      };
+    }, this).forEach(aCallback, context);
+  };
+
+/**
+ * Returns all generated line and column information for the original source,
+ * line, and column provided. If no column is provided, returns all mappings
+ * corresponding to a either the line we are searching for or the next
+ * closest line that has any mappings. Otherwise, returns all mappings
+ * corresponding to the given line and either the column we are searching for
+ * or the next closest column that has any offsets.
+ *
+ * The only argument is an object with the following properties:
+ *
+ *   - source: The filename of the original source.
+ *   - line: The line number in the original source.
+ *   - column: Optional. the column number in the original source.
+ *
+ * and an array of objects is returned, each with the following properties:
+ *
+ *   - line: The line number in the generated source, or null.
+ *   - column: The column number in the generated source, or null.
+ */
+SourceMapConsumer.prototype.allGeneratedPositionsFor =
+  function SourceMapConsumer_allGeneratedPositionsFor(aArgs) {
+    var line = util.getArg(aArgs, 'line');
+
+    // When there is no exact match, BasicSourceMapConsumer.prototype._findMapping
+    // returns the index of the closest mapping less than the needle. By
+    // setting needle.originalColumn to 0, we thus find the last mapping for
+    // the given line, provided such a mapping exists.
+    var needle = {
+      source: util.getArg(aArgs, 'source'),
+      originalLine: line,
+      originalColumn: util.getArg(aArgs, 'column', 0)
+    };
+
+    if (this.sourceRoot != null) {
+      needle.source = util.relative(this.sourceRoot, needle.source);
+    }
+    if (!this._sources.has(needle.source)) {
+      return [];
+    }
+    needle.source = this._sources.indexOf(needle.source);
+
+    var mappings = [];
+
+    var index = this._findMapping(needle,
+                                  this._originalMappings,
+                                  "originalLine",
+                                  "originalColumn",
+                                  util.compareByOriginalPositions,
+                                  binarySearch.LEAST_UPPER_BOUND);
+    if (index >= 0) {
+      var mapping = this._originalMappings[index];
+
+      if (aArgs.column === undefined) {
+        var originalLine = mapping.originalLine;
+
+        // Iterate until either we run out of mappings, or we run into
+        // a mapping for a different line than the one we found. Since
+        // mappings are sorted, this is guaranteed to find all mappings for
+        // the line we found.
+        while (mapping && mapping.originalLine === originalLine) {
+          mappings.push({
+            line: util.getArg(mapping, 'generatedLine', null),
+            column: util.getArg(mapping, 'generatedColumn', null),
+            lastColumn: util.getArg(mapping, 'lastGeneratedColumn', null)
+          });
+
+          mapping = this._originalMappings[++index];
+        }
+      } else {
+        var originalColumn = mapping.originalColumn;
+
+        // Iterate until either we run out of mappings, or we run into
+        // a mapping for a different line than the one we were searching for.
+        // Since mappings are sorted, this is guaranteed to find all mappings for
+        // the line we are searching for.
+        while (mapping &&
+               mapping.originalLine === line &&
+               mapping.originalColumn == originalColumn) {
+          mappings.push({
+            line: util.getArg(mapping, 'generatedLine', null),
+            column: util.getArg(mapping, 'generatedColumn', null),
+            lastColumn: util.getArg(mapping, 'lastGeneratedColumn', null)
+          });
+
+          mapping = this._originalMappings[++index];
+        }
+      }
+    }
+
+    return mappings;
+  };
+
+exports.SourceMapConsumer = SourceMapConsumer;
+
+/**
+ * A BasicSourceMapConsumer instance represents a parsed source map which we can
+ * query for information about the original file positions by giving it a file
+ * position in the generated source.
+ *
+ * The only parameter is the raw source map (either as a JSON string, or
+ * already parsed to an object). According to the spec, source maps have the
+ * following attributes:
+ *
+ *   - version: Which version of the source map spec this map is following.
+ *   - sources: An array of URLs to the original source files.
+ *   - names: An array of identifiers which can be referrenced by individual mappings.
+ *   - sourceRoot: Optional. The URL root from which all sources are relative.
+ *   - sourcesContent: Optional. An array of contents of the original source files.
+ *   - mappings: A string of base64 VLQs which contain the actual mappings.
+ *   - file: Optional. The generated file this source map is associated with.
+ *
+ * Here is an example source map, taken from the source map spec[0]:
+ *
+ *     {
+ *       version : 3,
+ *       file: "out.js",
+ *       sourceRoot : "",
+ *       sources: ["foo.js", "bar.js"],
+ *       names: ["src", "maps", "are", "fun"],
+ *       mappings: "AA,AB;;ABCDE;"
+ *     }
+ *
+ * [0]: https://docs.google.com/document/d/1U1RGAehQwRypUTovF1KRlpiOFze0b-_2gc6fAH0KY0k/edit?pli=1#
+ */
+function BasicSourceMapConsumer(aSourceMap) {
+  var sourceMap = aSourceMap;
+  if (typeof aSourceMap === 'string') {
+    sourceMap = JSON.parse(aSourceMap.replace(/^\)\]\}'/, ''));
+  }
+
+  var version = util.getArg(sourceMap, 'version');
+  var sources = util.getArg(sourceMap, 'sources');
+  // Sass 3.3 leaves out the 'names' array, so we deviate from the spec (which
+  // requires the array) to play nice here.
+  var names = util.getArg(sourceMap, 'names', []);
+  var sourceRoot = util.getArg(sourceMap, 'sourceRoot', null);
+  var sourcesContent = util.getArg(sourceMap, 'sourcesContent', null);
+  var mappings = util.getArg(sourceMap, 'mappings');
+  var file = util.getArg(sourceMap, 'file', null);
+
+  // Once again, Sass deviates from the spec and supplies the version as a
+  // string rather than a number, so we use loose equality checking here.
+  if (version != this._version) {
+    throw new Error('Unsupported version: ' + version);
+  }
+
+  sources = sources
+    .map(String)
+    // Some source maps produce relative source paths like "./foo.js" instead of
+    // "foo.js".  Normalize these first so that future comparisons will succeed.
+    // See bugzil.la/1090768.
+    .map(util.normalize)
+    // Always ensure that absolute sources are internally stored relative to
+    // the source root, if the source root is absolute. Not doing this would
+    // be particularly problematic when the source root is a prefix of the
+    // source (valid, but why??). See github issue #199 and bugzil.la/1188982.
+    .map(function (source) {
+      return sourceRoot && util.isAbsolute(sourceRoot) && util.isAbsolute(source)
+        ? util.relative(sourceRoot, source)
+        : source;
+    });
+
+  // Pass `true` below to allow duplicate names and sources. While source maps
+  // are intended to be compressed and deduplicated, the TypeScript compiler
+  // sometimes generates source maps with duplicates in them. See Github issue
+  // #72 and bugzil.la/889492.
+  this._names = ArraySet.fromArray(names.map(String), true);
+  this._sources = ArraySet.fromArray(sources, true);
+
+  this.sourceRoot = sourceRoot;
+  this.sourcesContent = sourcesContent;
+  this._mappings = mappings;
+  this.file = file;
+}
+
+BasicSourceMapConsumer.prototype = Object.create(SourceMapConsumer.prototype);
+BasicSourceMapConsumer.prototype.consumer = SourceMapConsumer;
+
+/**
+ * Create a BasicSourceMapConsumer from a SourceMapGenerator.
+ *
+ * @param SourceMapGenerator aSourceMap
+ *        The source map that will be consumed.
+ * @returns BasicSourceMapConsumer
+ */
+BasicSourceMapConsumer.fromSourceMap =
+  function SourceMapConsumer_fromSourceMap(aSourceMap) {
+    var smc = Object.create(BasicSourceMapConsumer.prototype);
+
+    var names = smc._names = ArraySet.fromArray(aSourceMap._names.toArray(), true);
+    var sources = smc._sources = ArraySet.fromArray(aSourceMap._sources.toArray(), true);
+    smc.sourceRoot = aSourceMap._sourceRoot;
+    smc.sourcesContent = aSourceMap._generateSourcesContent(smc._sources.toArray(),
+                                                            smc.sourceRoot);
+    smc.file = aSourceMap._file;
+
+    // Because we are modifying the entries (by converting string sources and
+    // names to indices into the sources and names ArraySets), we have to make
+    // a copy of the entry or else bad things happen. Shared mutable state
+    // strikes again! See github issue #191.
+
+    var generatedMappings = aSourceMap._mappings.toArray().slice();
+    var destGeneratedMappings = smc.__generatedMappings = [];
+    var destOriginalMappings = smc.__originalMappings = [];
+
+    for (var i = 0, length = generatedMappings.length; i < length; i++) {
+      var srcMapping = generatedMappings[i];
+      var destMapping = new Mapping;
+      destMapping.generatedLine = srcMapping.generatedLine;
+      destMapping.generatedColumn = srcMapping.generatedColumn;
+
+      if (srcMapping.source) {
+        destMapping.source = sources.indexOf(srcMapping.source);
+        destMapping.originalLine = srcMapping.originalLine;
+        destMapping.originalColumn = srcMapping.originalColumn;
+
+        if (srcMapping.name) {
+          destMapping.name = names.indexOf(srcMapping.name);
+        }
+
+        destOriginalMappings.push(destMapping);
+      }
+
+      destGeneratedMappings.push(destMapping);
+    }
+
+    quickSort(smc.__originalMappings, util.compareByOriginalPositions);
+
+    return smc;
+  };
+
+/**
+ * The version of the source mapping spec that we are consuming.
+ */
+BasicSourceMapConsumer.prototype._version = 3;
+
+/**
+ * The list of original sources.
+ */
+Object.defineProperty(BasicSourceMapConsumer.prototype, 'sources', {
+  get: function () {
+    return this._sources.toArray().map(function (s) {
+      return this.sourceRoot != null ? util.join(this.sourceRoot, s) : s;
+    }, this);
+  }
+});
+
+/**
+ * Provide the JIT with a nice shape / hidden class.
+ */
+function Mapping() {
+  this.generatedLine = 0;
+  this.generatedColumn = 0;
+  this.source = null;
+  this.originalLine = null;
+  this.originalColumn = null;
+  this.name = null;
+}
+
+/**
+ * Parse the mappings in a string in to a data structure which we can easily
+ * query (the ordered arrays in the `this.__generatedMappings` and
+ * `this.__originalMappings` properties).
+ */
+BasicSourceMapConsumer.prototype._parseMappings =
+  function SourceMapConsumer_parseMappings(aStr, aSourceRoot) {
+    var generatedLine = 1;
+    var previousGeneratedColumn = 0;
+    var previousOriginalLine = 0;
+    var previousOriginalColumn = 0;
+    var previousSource = 0;
+    var previousName = 0;
+    var length = aStr.length;
+    var index = 0;
+    var cachedSegments = {};
+    var temp = {};
+    var originalMappings = [];
+    var generatedMappings = [];
+    var mapping, str, segment, end, value;
+
+    while (index < length) {
+      if (aStr.charAt(index) === ';') {
+        generatedLine++;
+        index++;
+        previousGeneratedColumn = 0;
+      }
+      else if (aStr.charAt(index) === ',') {
+        index++;
+      }
+      else {
+        mapping = new Mapping();
+        mapping.generatedLine = generatedLine;
+
+        // Because each offset is encoded relative to the previous one,
+        // many segments often have the same encoding. We can exploit this
+        // fact by caching the parsed variable length fields of each segment,
+        // allowing us to avoid a second parse if we encounter the same
+        // segment again.
+        for (end = index; end < length; end++) {
+          if (this._charIsMappingSeparator(aStr, end)) {
+            break;
+          }
+        }
+        str = aStr.slice(index, end);
+
+        segment = cachedSegments[str];
+        if (segment) {
+          index += str.length;
+        } else {
+          segment = [];
+          while (index < end) {
+            base64VLQ.decode(aStr, index, temp);
+            value = temp.value;
+            index = temp.rest;
+            segment.push(value);
+          }
+
+          if (segment.length === 2) {
+            throw new Error('Found a source, but no line and column');
+          }
+
+          if (segment.length === 3) {
+            throw new Error('Found a source and line, but no column');
+          }
+
+          cachedSegments[str] = segment;
+        }
+
+        // Generated column.
+        mapping.generatedColumn = previousGeneratedColumn + segment[0];
+        previousGeneratedColumn = mapping.generatedColumn;
+
+        if (segment.length > 1) {
+          // Original source.
+          mapping.source = previousSource + segment[1];
+          previousSource += segment[1];
+
+          // Original line.
+          mapping.originalLine = previousOriginalLine + segment[2];
+          previousOriginalLine = mapping.originalLine;
+          // Lines are stored 0-based
+          mapping.originalLine += 1;
+
+          // Original column.
+          mapping.originalColumn = previousOriginalColumn + segment[3];
+          previousOriginalColumn = mapping.originalColumn;
+
+          if (segment.length > 4) {
+            // Original name.
+            mapping.name = previousName + segment[4];
+            previousName += segment[4];
+          }
+        }
+
+        generatedMappings.push(mapping);
+        if (typeof mapping.originalLine === 'number') {
+          originalMappings.push(mapping);
+        }
+      }
+    }
+
+    quickSort(generatedMappings, util.compareByGeneratedPositionsDeflated);
+    this.__generatedMappings = generatedMappings;
+
+    quickSort(originalMappings, util.compareByOriginalPositions);
+    this.__originalMappings = originalMappings;
+  };
+
+/**
+ * Find the mapping that best matches the hypothetical "needle" mapping that
+ * we are searching for in the given "haystack" of mappings.
+ */
+BasicSourceMapConsumer.prototype._findMapping =
+  function SourceMapConsumer_findMapping(aNeedle, aMappings, aLineName,
+                                         aColumnName, aComparator, aBias) {
+    // To return the position we are searching for, we must first find the
+    // mapping for the given position and then return the opposite position it
+    // points to. Because the mappings are sorted, we can use binary search to
+    // find the best mapping.
+
+    if (aNeedle[aLineName] <= 0) {
+      throw new TypeError('Line must be greater than or equal to 1, got '
+                          + aNeedle[aLineName]);
+    }
+    if (aNeedle[aColumnName] < 0) {
+      throw new TypeError('Column must be greater than or equal to 0, got '
+                          + aNeedle[aColumnName]);
+    }
+
+    return binarySearch.search(aNeedle, aMappings, aComparator, aBias);
+  };
+
+/**
+ * Compute the last column for each generated mapping. The last column is
+ * inclusive.
+ */
+BasicSourceMapConsumer.prototype.computeColumnSpans =
+  function SourceMapConsumer_computeColumnSpans() {
+    for (var index = 0; index < this._generatedMappings.length; ++index) {
+      var mapping = this._generatedMappings[index];
+
+      // Mappings do not contain a field for the last generated columnt. We
+      // can come up with an optimistic estimate, however, by assuming that
+      // mappings are contiguous (i.e. given two consecutive mappings, the
+      // first mapping ends where the second one starts).
+      if (index + 1 < this._generatedMappings.length) {
+        var nextMapping = this._generatedMappings[index + 1];
+
+        if (mapping.generatedLine === nextMapping.generatedLine) {
+          mapping.lastGeneratedColumn = nextMapping.generatedColumn - 1;
+          continue;
+        }
+      }
+
+      // The last mapping for each line spans the entire line.
+      mapping.lastGeneratedColumn = Infinity;
+    }
+  };
+
+/**
+ * Returns the original source, line, and column information for the generated
+ * source's line and column positions provided. The only argument is an object
+ * with the following properties:
+ *
+ *   - line: The line number in the generated source.
+ *   - column: The column number in the generated source.
+ *   - bias: Either 'SourceMapConsumer.GREATEST_LOWER_BOUND' or
+ *     'SourceMapConsumer.LEAST_UPPER_BOUND'. Specifies whether to return the
+ *     closest element that is smaller than or greater than the one we are
+ *     searching for, respectively, if the exact element cannot be found.
+ *     Defaults to 'SourceMapConsumer.GREATEST_LOWER_BOUND'.
+ *
+ * and an object is returned with the following properties:
+ *
+ *   - source: The original source file, or null.
+ *   - line: The line number in the original source, or null.
+ *   - column: The column number in the original source, or null.
+ *   - name: The original identifier, or null.
+ */
+BasicSourceMapConsumer.prototype.originalPositionFor =
+  function SourceMapConsumer_originalPositionFor(aArgs) {
+    var needle = {
+      generatedLine: util.getArg(aArgs, 'line'),
+      generatedColumn: util.getArg(aArgs, 'column')
+    };
+
+    var index = this._findMapping(
+      needle,
+      this._generatedMappings,
+      "generatedLine",
+      "generatedColumn",
+      util.compareByGeneratedPositionsDeflated,
+      util.getArg(aArgs, 'bias', SourceMapConsumer.GREATEST_LOWER_BOUND)
+    );
+
+    if (index >= 0) {
+      var mapping = this._generatedMappings[index];
+
+      if (mapping.generatedLine === needle.generatedLine) {
+        var source = util.getArg(mapping, 'source', null);
+        if (source !== null) {
+          source = this._sources.at(source);
+          if (this.sourceRoot != null) {
+            source = util.join(this.sourceRoot, source);
+          }
+        }
+        var name = util.getArg(mapping, 'name', null);
+        if (name !== null) {
+          name = this._names.at(name);
+        }
+        return {
+          source: source,
+          line: util.getArg(mapping, 'originalLine', null),
+          column: util.getArg(mapping, 'originalColumn', null),
+          name: name
+        };
+      }
+    }
+
+    return {
+      source: null,
+      line: null,
+      column: null,
+      name: null
+    };
+  };
+
+/**
+ * Return true if we have the source content for every source in the source
+ * map, false otherwise.
+ */
+BasicSourceMapConsumer.prototype.hasContentsOfAllSources =
+  function BasicSourceMapConsumer_hasContentsOfAllSources() {
+    if (!this.sourcesContent) {
+      return false;
+    }
+    return this.sourcesContent.length >= this._sources.size() &&
+      !this.sourcesContent.some(function (sc) { return sc == null; });
+  };
+
+/**
+ * Returns the original source content. The only argument is the url of the
+ * original source file. Returns null if no original source content is
+ * available.
+ */
+BasicSourceMapConsumer.prototype.sourceContentFor =
+  function SourceMapConsumer_sourceContentFor(aSource, nullOnMissing) {
+    if (!this.sourcesContent) {
+      return null;
+    }
+
+    if (this.sourceRoot != null) {
+      aSource = util.relative(this.sourceRoot, aSource);
+    }
+
+    if (this._sources.has(aSource)) {
+      return this.sourcesContent[this._sources.indexOf(aSource)];
+    }
+
+    var url;
+    if (this.sourceRoot != null
+        && (url = util.urlParse(this.sourceRoot))) {
+      // XXX: file:// URIs and absolute paths lead to unexpected behavior for
+      // many users. We can help them out when they expect file:// URIs to
+      // behave like it would if they were running a local HTTP server. See
+      // https://bugzilla.mozilla.org/show_bug.cgi?id=885597.
+      var fileUriAbsPath = aSource.replace(/^file:\/\//, "");
+      if (url.scheme == "file"
+          && this._sources.has(fileUriAbsPath)) {
+        return this.sourcesContent[this._sources.indexOf(fileUriAbsPath)]
+      }
+
+      if ((!url.path || url.path == "/")
+          && this._sources.has("/" + aSource)) {
+        return this.sourcesContent[this._sources.indexOf("/" + aSource)];
+      }
+    }
+
+    // This function is used recursively from
+    // IndexedSourceMapConsumer.prototype.sourceContentFor. In that case, we
+    // don't want to throw if we can't find the source - we just want to
+    // return null, so we provide a flag to exit gracefully.
+    if (nullOnMissing) {
+      return null;
+    }
+    else {
+      throw new Error('"' + aSource + '" is not in the SourceMap.');
+    }
+  };
+
+/**
+ * Returns the generated line and column information for the original source,
+ * line, and column positions provided. The only argument is an object with
+ * the following properties:
+ *
+ *   - source: The filename of the original source.
+ *   - line: The line number in the original source.
+ *   - column: The column number in the original source.
+ *   - bias: Either 'SourceMapConsumer.GREATEST_LOWER_BOUND' or
+ *     'SourceMapConsumer.LEAST_UPPER_BOUND'. Specifies whether to return the
+ *     closest element that is smaller than or greater than the one we are
+ *     searching for, respectively, if the exact element cannot be found.
+ *     Defaults to 'SourceMapConsumer.GREATEST_LOWER_BOUND'.
+ *
+ * and an object is returned with the following properties:
+ *
+ *   - line: The line number in the generated source, or null.
+ *   - column: The column number in the generated source, or null.
+ */
+BasicSourceMapConsumer.prototype.generatedPositionFor =
+  function SourceMapConsumer_generatedPositionFor(aArgs) {
+    var source = util.getArg(aArgs, 'source');
+    if (this.sourceRoot != null) {
+      source = util.relative(this.sourceRoot, source);
+    }
+    if (!this._sources.has(source)) {
+      return {
+        line: null,
+        column: null,
+        lastColumn: null
+      };
+    }
+    source = this._sources.indexOf(source);
+
+    var needle = {
+      source: source,
+      originalLine: util.getArg(aArgs, 'line'),
+      originalColumn: util.getArg(aArgs, 'column')
+    };
+
+    var index = this._findMapping(
+      needle,
+      this._originalMappings,
+      "originalLine",
+      "originalColumn",
+      util.compareByOriginalPositions,
+      util.getArg(aArgs, 'bias', SourceMapConsumer.GREATEST_LOWER_BOUND)
+    );
+
+    if (index >= 0) {
+      var mapping = this._originalMappings[index];
+
+      if (mapping.source === needle.source) {
+        return {
+          line: util.getArg(mapping, 'generatedLine', null),
+          column: util.getArg(mapping, 'generatedColumn', null),
+          lastColumn: util.getArg(mapping, 'lastGeneratedColumn', null)
+        };
+      }
+    }
+
+    return {
+      line: null,
+      column: null,
+      lastColumn: null
+    };
+  };
+
+exports.BasicSourceMapConsumer = BasicSourceMapConsumer;
+
+/**
+ * An IndexedSourceMapConsumer instance represents a parsed source map which
+ * we can query for information. It differs from BasicSourceMapConsumer in
+ * that it takes "indexed" source maps (i.e. ones with a "sections" field) as
+ * input.
+ *
+ * The only parameter is a raw source map (either as a JSON string, or already
+ * parsed to an object). According to the spec for indexed source maps, they
+ * have the following attributes:
+ *
+ *   - version: Which version of the source map spec this map is following.
+ *   - file: Optional. The generated file this source map is associated with.
+ *   - sections: A list of section definitions.
+ *
+ * Each value under the "sections" field has two fields:
+ *   - offset: The offset into the original specified at which this section
+ *       begins to apply, defined as an object with a "line" and "column"
+ *       field.
+ *   - map: A source map definition. This source map could also be indexed,
+ *       but doesn't have to be.
+ *
+ * Instead of the "map" field, it's also possible to have a "url" field
+ * specifying a URL to retrieve a source map from, but that's currently
+ * unsupported.
+ *
+ * Here's an example source map, taken from the source map spec[0], but
+ * modified to omit a section which uses the "url" field.
+ *
+ *  {
+ *    version : 3,
+ *    file: "app.js",
+ *    sections: [{
+ *      offset: {line:100, column:10},
+ *      map: {
+ *        version : 3,
+ *        file: "section.js",
+ *        sources: ["foo.js", "bar.js"],
+ *        names: ["src", "maps", "are", "fun"],
+ *        mappings: "AAAA,E;;ABCDE;"
+ *      }
+ *    }],
+ *  }
+ *
+ * [0]: https://docs.google.com/document/d/1U1RGAehQwRypUTovF1KRlpiOFze0b-_2gc6fAH0KY0k/edit#heading=h.535es3xeprgt
+ */
+function IndexedSourceMapConsumer(aSourceMap) {
+  var sourceMap = aSourceMap;
+  if (typeof aSourceMap === 'string') {
+    sourceMap = JSON.parse(aSourceMap.replace(/^\)\]\}'/, ''));
+  }
+
+  var version = util.getArg(sourceMap, 'version');
+  var sections = util.getArg(sourceMap, 'sections');
+
+  if (version != this._version) {
+    throw new Error('Unsupported version: ' + version);
+  }
+
+  this._sources = new ArraySet();
+  this._names = new ArraySet();
+
+  var lastOffset = {
+    line: -1,
+    column: 0
+  };
+  this._sections = sections.map(function (s) {
+    if (s.url) {
+      // The url field will require support for asynchronicity.
+      // See https://github.com/mozilla/source-map/issues/16
+      throw new Error('Support for url field in sections not implemented.');
+    }
+    var offset = util.getArg(s, 'offset');
+    var offsetLine = util.getArg(offset, 'line');
+    var offsetColumn = util.getArg(offset, 'column');
+
+    if (offsetLine < lastOffset.line ||
+        (offsetLine === lastOffset.line && offsetColumn < lastOffset.column)) {
+      throw new Error('Section offsets must be ordered and non-overlapping.');
+    }
+    lastOffset = offset;
+
+    return {
+      generatedOffset: {
+        // The offset fields are 0-based, but we use 1-based indices when
+        // encoding/decoding from VLQ.
+        generatedLine: offsetLine + 1,
+        generatedColumn: offsetColumn + 1
+      },
+      consumer: new SourceMapConsumer(util.getArg(s, 'map'))
+    }
+  });
+}
+
+IndexedSourceMapConsumer.prototype = Object.create(SourceMapConsumer.prototype);
+IndexedSourceMapConsumer.prototype.constructor = SourceMapConsumer;
+
+/**
+ * The version of the source mapping spec that we are consuming.
+ */
+IndexedSourceMapConsumer.prototype._version = 3;
+
+/**
+ * The list of original sources.
+ */
+Object.defineProperty(IndexedSourceMapConsumer.prototype, 'sources', {
+  get: function () {
+    var sources = [];
+    for (var i = 0; i < this._sections.length; i++) {
+      for (var j = 0; j < this._sections[i].consumer.sources.length; j++) {
+        sources.push(this._sections[i].consumer.sources[j]);
+      }
+    }
+    return sources;
+  }
+});
+
+/**
+ * Returns the original source, line, and column information for the generated
+ * source's line and column positions provided. The only argument is an object
+ * with the following properties:
+ *
+ *   - line: The line number in the generated source.
+ *   - column: The column number in the generated source.
+ *
+ * and an object is returned with the following properties:
+ *
+ *   - source: The original source file, or null.
+ *   - line: The line number in the original source, or null.
+ *   - column: The column number in the original source, or null.
+ *   - name: The original identifier, or null.
+ */
+IndexedSourceMapConsumer.prototype.originalPositionFor =
+  function IndexedSourceMapConsumer_originalPositionFor(aArgs) {
+    var needle = {
+      generatedLine: util.getArg(aArgs, 'line'),
+      generatedColumn: util.getArg(aArgs, 'column')
+    };
+
+    // Find the section containing the generated position we're trying to map
+    // to an original position.
+    var sectionIndex = binarySearch.search(needle, this._sections,
+      function(needle, section) {
+        var cmp = needle.generatedLine - section.generatedOffset.generatedLine;
+        if (cmp) {
+          return cmp;
+        }
+
+        return (needle.generatedColumn -
+                section.generatedOffset.generatedColumn);
+      });
+    var section = this._sections[sectionIndex];
+
+    if (!section) {
+      return {
+        source: null,
+        line: null,
+        column: null,
+        name: null
+      };
+    }
+
+    return section.consumer.originalPositionFor({
+      line: needle.generatedLine -
+        (section.generatedOffset.generatedLine - 1),
+      column: needle.generatedColumn -
+        (section.generatedOffset.generatedLine === needle.generatedLine
+         ? section.generatedOffset.generatedColumn - 1
+         : 0),
+      bias: aArgs.bias
+    });
+  };
+
+/**
+ * Return true if we have the source content for every source in the source
+ * map, false otherwise.
+ */
+IndexedSourceMapConsumer.prototype.hasContentsOfAllSources =
+  function IndexedSourceMapConsumer_hasContentsOfAllSources() {
+    return this._sections.every(function (s) {
+      return s.consumer.hasContentsOfAllSources();
+    });
+  };
+
+/**
+ * Returns the original source content. The only argument is the url of the
+ * original source file. Returns null if no original source content is
+ * available.
+ */
+IndexedSourceMapConsumer.prototype.sourceContentFor =
+  function IndexedSourceMapConsumer_sourceContentFor(aSource, nullOnMissing) {
+    for (var i = 0; i < this._sections.length; i++) {
+      var section = this._sections[i];
+
+      var content = section.consumer.sourceContentFor(aSource, true);
+      if (content) {
+        return content;
+      }
+    }
+    if (nullOnMissing) {
+      return null;
+    }
+    else {
+      throw new Error('"' + aSource + '" is not in the SourceMap.');
+    }
+  };
+
+/**
+ * Returns the generated line and column information for the original source,
+ * line, and column positions provided. The only argument is an object with
+ * the following properties:
+ *
+ *   - source: The filename of the original source.
+ *   - line: The line number in the original source.
+ *   - column: The column number in the original source.
+ *
+ * and an object is returned with the following properties:
+ *
+ *   - line: The line number in the generated source, or null.
+ *   - column: The column number in the generated source, or null.
+ */
+IndexedSourceMapConsumer.prototype.generatedPositionFor =
+  function IndexedSourceMapConsumer_generatedPositionFor(aArgs) {
+    for (var i = 0; i < this._sections.length; i++) {
+      var section = this._sections[i];
+
+      // Only consider this section if the requested source is in the list of
+      // sources of the consumer.
+      if (section.consumer.sources.indexOf(util.getArg(aArgs, 'source')) === -1) {
+        continue;
+      }
+      var generatedPosition = section.consumer.generatedPositionFor(aArgs);
+      if (generatedPosition) {
+        var ret = {
+          line: generatedPosition.line +
+            (section.generatedOffset.generatedLine - 1),
+          column: generatedPosition.column +
+            (section.generatedOffset.generatedLine === generatedPosition.line
+             ? section.generatedOffset.generatedColumn - 1
+             : 0)
+        };
+        return ret;
+      }
+    }
+
+    return {
+      line: null,
+      column: null
+    };
+  };
+
+/**
+ * Parse the mappings in a string in to a data structure which we can easily
+ * query (the ordered arrays in the `this.__generatedMappings` and
+ * `this.__originalMappings` properties).
+ */
+IndexedSourceMapConsumer.prototype._parseMappings =
+  function IndexedSourceMapConsumer_parseMappings(aStr, aSourceRoot) {
+    this.__generatedMappings = [];
+    this.__originalMappings = [];
+    for (var i = 0; i < this._sections.length; i++) {
+      var section = this._sections[i];
+      var sectionMappings = section.consumer._generatedMappings;
+      for (var j = 0; j < sectionMappings.length; j++) {
+        var mapping = sectionMappings[j];
+
+        var source = section.consumer._sources.at(mapping.source);
+        if (section.consumer.sourceRoot !== null) {
+          source = util.join(section.consumer.sourceRoot, source);
+        }
+        this._sources.add(source);
+        source = this._sources.indexOf(source);
+
+        var name = section.consumer._names.at(mapping.name);
+        this._names.add(name);
+        name = this._names.indexOf(name);
+
+        // The mappings coming from the consumer for the section have
+        // generated positions relative to the start of the section, so we
+        // need to offset them to be relative to the start of the concatenated
+        // generated file.
+        var adjustedMapping = {
+          source: source,
+          generatedLine: mapping.generatedLine +
+            (section.generatedOffset.generatedLine - 1),
+          generatedColumn: mapping.generatedColumn +
+            (section.generatedOffset.generatedLine === mapping.generatedLine
+            ? section.generatedOffset.generatedColumn - 1
+            : 0),
+          originalLine: mapping.originalLine,
+          originalColumn: mapping.originalColumn,
+          name: name
+        };
+
+        this.__generatedMappings.push(adjustedMapping);
+        if (typeof adjustedMapping.originalLine === 'number') {
+          this.__originalMappings.push(adjustedMapping);
+        }
+      }
+    }
+
+    quickSort(this.__generatedMappings, util.compareByGeneratedPositionsDeflated);
+    quickSort(this.__originalMappings, util.compareByOriginalPositions);
+  };
+
+exports.IndexedSourceMapConsumer = IndexedSourceMapConsumer;