| /* -*- Mode: js; js-indent-level: 2; -*- */ |
| /* |
| * Copyright 2014 Mozilla Foundation and contributors |
| * Licensed under the New BSD license. See LICENSE or: |
| * http://opensource.org/licenses/BSD-3-Clause |
| */ |
| |
| var util = require('./util'); |
| |
| /** |
| * Determine whether mappingB is after mappingA with respect to generated |
| * position. |
| */ |
| function generatedPositionAfter(mappingA, mappingB) { |
| // Optimized for most common case |
| var lineA = mappingA.generatedLine; |
| var lineB = mappingB.generatedLine; |
| var columnA = mappingA.generatedColumn; |
| var columnB = mappingB.generatedColumn; |
| return lineB > lineA || lineB == lineA && columnB >= columnA || |
| util.compareByGeneratedPositionsInflated(mappingA, mappingB) <= 0; |
| } |
| |
| /** |
| * A data structure to provide a sorted view of accumulated mappings in a |
| * performance conscious manner. It trades a neglibable overhead in general |
| * case for a large speedup in case of mappings being added in order. |
| */ |
| function MappingList() { |
| this._array = []; |
| this._sorted = true; |
| // Serves as infimum |
| this._last = {generatedLine: -1, generatedColumn: 0}; |
| } |
| |
| /** |
| * Iterate through internal items. This method takes the same arguments that |
| * `Array.prototype.forEach` takes. |
| * |
| * NOTE: The order of the mappings is NOT guaranteed. |
| */ |
| MappingList.prototype.unsortedForEach = |
| function MappingList_forEach(aCallback, aThisArg) { |
| this._array.forEach(aCallback, aThisArg); |
| }; |
| |
| /** |
| * Add the given source mapping. |
| * |
| * @param Object aMapping |
| */ |
| MappingList.prototype.add = function MappingList_add(aMapping) { |
| if (generatedPositionAfter(this._last, aMapping)) { |
| this._last = aMapping; |
| this._array.push(aMapping); |
| } else { |
| this._sorted = false; |
| this._array.push(aMapping); |
| } |
| }; |
| |
| /** |
| * Returns the flat, sorted array of mappings. The mappings are sorted by |
| * generated position. |
| * |
| * WARNING: This method returns internal data without copying, for |
| * performance. The return value must NOT be mutated, and should be treated as |
| * an immutable borrow. If you want to take ownership, you must make your own |
| * copy. |
| */ |
| MappingList.prototype.toArray = function MappingList_toArray() { |
| if (!this._sorted) { |
| this._array.sort(util.compareByGeneratedPositionsInflated); |
| this._sorted = true; |
| } |
| return this._array; |
| }; |
| |
| exports.MappingList = MappingList; |