MACHIN

30/node_modules/source-map/lib/array-set.js

@@ -0,0 +1,121 @@
+/* -*- 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 has = Object.prototype.hasOwnProperty;
+var hasNativeMap = typeof Map !== "undefined";
+
+/**
+ * A data structure which is a combination of an array and a set. Adding a new
+ * member is O(1), testing for membership is O(1), and finding the index of an
+ * element is O(1). Removing elements from the set is not supported. Only
+ * strings are supported for membership.
+ */
+function ArraySet() {
+  this._array = [];
+  this._set = hasNativeMap ? new Map() : Object.create(null);
+}
+
+/**
+ * Static method for creating ArraySet instances from an existing array.
+ */
+ArraySet.fromArray = function ArraySet_fromArray(aArray, aAllowDuplicates) {
+  var set = new ArraySet();
+  for (var i = 0, len = aArray.length; i < len; i++) {
+    set.add(aArray[i], aAllowDuplicates);
+  }
+  return set;
+};
+
+/**
+ * Return how many unique items are in this ArraySet. If duplicates have been
+ * added, than those do not count towards the size.
+ *
+ * @returns Number
+ */
+ArraySet.prototype.size = function ArraySet_size() {
+  return hasNativeMap ? this._set.size : Object.getOwnPropertyNames(this._set).length;
+};
+
+/**
+ * Add the given string to this set.
+ *
+ * @param String aStr
+ */
+ArraySet.prototype.add = function ArraySet_add(aStr, aAllowDuplicates) {
+  var sStr = hasNativeMap ? aStr : util.toSetString(aStr);
+  var isDuplicate = hasNativeMap ? this.has(aStr) : has.call(this._set, sStr);
+  var idx = this._array.length;
+  if (!isDuplicate || aAllowDuplicates) {
+    this._array.push(aStr);
+  }
+  if (!isDuplicate) {
+    if (hasNativeMap) {
+      this._set.set(aStr, idx);
+    } else {
+      this._set[sStr] = idx;
+    }
+  }
+};
+
+/**
+ * Is the given string a member of this set?
+ *
+ * @param String aStr
+ */
+ArraySet.prototype.has = function ArraySet_has(aStr) {
+  if (hasNativeMap) {
+    return this._set.has(aStr);
+  } else {
+    var sStr = util.toSetString(aStr);
+    return has.call(this._set, sStr);
+  }
+};
+
+/**
+ * What is the index of the given string in the array?
+ *
+ * @param String aStr
+ */
+ArraySet.prototype.indexOf = function ArraySet_indexOf(aStr) {
+  if (hasNativeMap) {
+    var idx = this._set.get(aStr);
+    if (idx >= 0) {
+        return idx;
+    }
+  } else {
+    var sStr = util.toSetString(aStr);
+    if (has.call(this._set, sStr)) {
+      return this._set[sStr];
+    }
+  }
+
+  throw new Error('"' + aStr + '" is not in the set.');
+};
+
+/**
+ * What is the element at the given index?
+ *
+ * @param Number aIdx
+ */
+ArraySet.prototype.at = function ArraySet_at(aIdx) {
+  if (aIdx >= 0 && aIdx < this._array.length) {
+    return this._array[aIdx];
+  }
+  throw new Error('No element indexed by ' + aIdx);
+};
+
+/**
+ * Returns the array representation of this set (which has the proper indices
+ * indicated by indexOf). Note that this is a copy of the internal array used
+ * for storing the members so that no one can mess with internal state.
+ */
+ArraySet.prototype.toArray = function ArraySet_toArray() {
+  return this._array.slice();
+};
+
+exports.ArraySet = ArraySet;