1 files changed, 334 insertions, 0 deletions
diff --git a/node_modules/lru-cache/lib/lru-cache.js b/node_modules/lru-cache/lib/lru-cache.js
new file mode 100644
index 000000000..2bbe653be
--- /dev/null
+++ b/node_modules/lru-cache/lib/lru-cache.js
@@ -0,0 +1,334 @@
+;(function () { // closure for web browsers
+
+if (typeof module === 'object' && module.exports) {
+  module.exports = LRUCache
+} else {
+  // just set the global for non-node platforms.
+  this.LRUCache = LRUCache
+}
+
+function hOP (obj, key) {
+  return Object.prototype.hasOwnProperty.call(obj, key)
+}
+
+function naiveLength () { return 1 }
+
+var didTypeWarning = false
+function typeCheckKey(key) {
+  if (!didTypeWarning && typeof key !== 'string' && typeof key !== 'number') {
+    didTypeWarning = true
+    console.error(new TypeError("LRU: key must be a string or number. Almost certainly a bug! " + typeof key).stack)
+  }
+}
+
+function LRUCache (options) {
+  if (!(this instanceof LRUCache))
+    return new LRUCache(options)
+
+  if (typeof options === 'number')
+    options = { max: options }
+
+  if (!options)
+    options = {}
+
+  this._max = options.max
+  // Kind of weird to have a default max of Infinity, but oh well.
+  if (!this._max || !(typeof this._max === "number") || this._max <= 0 )
+    this._max = Infinity
+
+  this._lengthCalculator = options.length || naiveLength
+  if (typeof this._lengthCalculator !== "function")
+    this._lengthCalculator = naiveLength
+
+  this._allowStale = options.stale || false
+  this._maxAge = options.maxAge || null
+  this._dispose = options.dispose
+  this.reset()
+}
+
+// resize the cache when the max changes.
+Object.defineProperty(LRUCache.prototype, "max",
+  { set : function (mL) {
+      if (!mL || !(typeof mL === "number") || mL <= 0 ) mL = Infinity
+      this._max = mL
+      if (this._length > this._max) trim(this)
+    }
+  , get : function () { return this._max }
+  , enumerable : true
+  })
+
+// resize the cache when the lengthCalculator changes.
+Object.defineProperty(LRUCache.prototype, "lengthCalculator",
+  { set : function (lC) {
+      if (typeof lC !== "function") {
+        this._lengthCalculator = naiveLength
+        this._length = this._itemCount
+        for (var key in this._cache) {
+          this._cache[key].length = 1
+        }
+      } else {
+        this._lengthCalculator = lC
+        this._length = 0
+        for (var key in this._cache) {
+          this._cache[key].length = this._lengthCalculator(this._cache[key].value)
+          this._length += this._cache[key].length
+        }
+      }
+
+      if (this._length > this._max) trim(this)
+    }
+  , get : function () { return this._lengthCalculator }
+  , enumerable : true
+  })
+
+Object.defineProperty(LRUCache.prototype, "length",
+  { get : function () { return this._length }
+  , enumerable : true
+  })
+
+
+Object.defineProperty(LRUCache.prototype, "itemCount",
+  { get : function () { return this._itemCount }
+  , enumerable : true
+  })
+
+LRUCache.prototype.forEach = function (fn, thisp) {
+  thisp = thisp || this
+  var i = 0
+  var itemCount = this._itemCount
+
+  for (var k = this._mru - 1; k >= 0 && i < itemCount; k--) if (this._lruList[k]) {
+    i++
+    var hit = this._lruList[k]
+    if (isStale(this, hit)) {
+      del(this, hit)
+      if (!this._allowStale) hit = undefined
+    }
+    if (hit) {
+      fn.call(thisp, hit.value, hit.key, this)
+    }
+  }
+}
+
+LRUCache.prototype.keys = function () {
+  var keys = new Array(this._itemCount)
+  var i = 0
+  for (var k = this._mru - 1; k >= 0 && i < this._itemCount; k--) if (this._lruList[k]) {
+    var hit = this._lruList[k]
+    keys[i++] = hit.key
+  }
+  return keys
+}
+
+LRUCache.prototype.values = function () {
+  var values = new Array(this._itemCount)
+  var i = 0
+  for (var k = this._mru - 1; k >= 0 && i < this._itemCount; k--) if (this._lruList[k]) {
+    var hit = this._lruList[k]
+    values[i++] = hit.value
+  }
+  return values
+}
+
+LRUCache.prototype.reset = function () {
+  if (this._dispose && this._cache) {
+    for (var k in this._cache) {
+      this._dispose(k, this._cache[k].value)
+    }
+  }
+
+  this._cache = Object.create(null) // hash of items by key
+  this._lruList = Object.create(null) // list of items in order of use recency
+  this._mru = 0 // most recently used
+  this._lru = 0 // least recently used
+  this._length = 0 // number of items in the list
+  this._itemCount = 0
+}
+
+LRUCache.prototype.dump = function () {
+  var arr = []
+  var i = 0
+
+  for (var k = this._mru - 1; k >= 0 && i < this._itemCount; k--) if (this._lruList[k]) {
+    var hit = this._lruList[k]
+    if (!isStale(this, hit)) {
+      //Do not store staled hits
+      ++i
+      arr.push({
+        k: hit.key,
+        v: hit.value,
+        e: hit.now + (hit.maxAge || 0)
+      });
+    }
+  }
+  //arr has the most read first
+  return arr
+}
+
+LRUCache.prototype.dumpLru = function () {
+  return this._lruList
+}
+
+LRUCache.prototype.set = function (key, value, maxAge) {
+  maxAge = maxAge || this._maxAge
+  typeCheckKey(key)
+
+  var now = maxAge ? Date.now() : 0
+  var len = this._lengthCalculator(value)
+
+  if (hOP(this._cache, key)) {
+    if (len > this._max) {
+      del(this, this._cache[key])
+      return false
+    }
+    // dispose of the old one before overwriting
+    if (this._dispose)
+      this._dispose(key, this._cache[key].value)
+
+    this._cache[key].now = now
+    this._cache[key].maxAge = maxAge
+    this._cache[key].value = value
+    this._length += (len - this._cache[key].length)
+    this._cache[key].length = len
+    this.get(key)
+
+    if (this._length > this._max)
+      trim(this)
+
+    return true
+  }
+
+  var hit = new Entry(key, value, this._mru++, len, now, maxAge)
+
+  // oversized objects fall out of cache automatically.
+  if (hit.length > this._max) {
+    if (this._dispose) this._dispose(key, value)
+    return false
+  }
+
+  this._length += hit.length
+  this._lruList[hit.lu] = this._cache[key] = hit
+  this._itemCount ++
+
+  if (this._length > this._max)
+    trim(this)
+
+  return true
+}
+
+LRUCache.prototype.has = function (key) {
+  typeCheckKey(key)
+  if (!hOP(this._cache, key)) return false
+  var hit = this._cache[key]
+  if (isStale(this, hit)) {
+    return false
+  }
+  return true
+}
+
+LRUCache.prototype.get = function (key) {
+  typeCheckKey(key)
+  return get(this, key, true)
+}
+
+LRUCache.prototype.peek = function (key) {
+  typeCheckKey(key)
+  return get(this, key, false)
+}
+
+LRUCache.prototype.pop = function () {
+  var hit = this._lruList[this._lru]
+  del(this, hit)
+  return hit || null
+}
+
+LRUCache.prototype.del = function (key) {
+  typeCheckKey(key)
+  del(this, this._cache[key])
+}
+
+LRUCache.prototype.load = function (arr) {
+  //reset the cache
+  this.reset();
+
+  var now = Date.now()
+  //A previous serialized cache has the most recent items first
+  for (var l = arr.length - 1; l >= 0; l-- ) {
+    var hit = arr[l]
+    typeCheckKey(hit.k)
+    var expiresAt = hit.e || 0
+    if (expiresAt === 0) {
+      //the item was created without expiration in a non aged cache
+      this.set(hit.k, hit.v)
+    } else {
+      var maxAge = expiresAt - now
+      //dont add already expired items
+      if (maxAge > 0) this.set(hit.k, hit.v, maxAge)
+    }
+  }
+}
+
+function get (self, key, doUse) {
+  typeCheckKey(key)
+  var hit = self._cache[key]
+  if (hit) {
+    if (isStale(self, hit)) {
+      del(self, hit)
+      if (!self._allowStale) hit = undefined
+    } else {
+      if (doUse) use(self, hit)
+    }
+    if (hit) hit = hit.value
+  }
+  return hit
+}
+
+function isStale(self, hit) {
+  if (!hit || (!hit.maxAge && !self._maxAge)) return false
+  var stale = false;
+  var diff = Date.now() - hit.now
+  if (hit.maxAge) {
+    stale = diff > hit.maxAge
+  } else {
+    stale = self._maxAge && (diff > self._maxAge)
+  }
+  return stale;
+}
+
+function use (self, hit) {
+  shiftLU(self, hit)
+  hit.lu = self._mru ++
+  self._lruList[hit.lu] = hit
+}
+
+function trim (self) {
+  while (self._lru < self._mru && self._length > self._max)
+    del(self, self._lruList[self._lru])
+}
+
+function shiftLU (self, hit) {
+  delete self._lruList[ hit.lu ]
+  while (self._lru < self._mru && !self._lruList[self._lru]) self._lru ++
+}
+
+function del (self, hit) {
+  if (hit) {
+    if (self._dispose) self._dispose(hit.key, hit.value)
+    self._length -= hit.length
+    self._itemCount --
+    delete self._cache[ hit.key ]
+    shiftLU(self, hit)
+  }
+}
+
+// classy, since V8 prefers predictable objects.
+function Entry (key, value, lu, length, now, maxAge) {
+  this.key = key
+  this.value = value
+  this.lu = lu
+  this.length = length
+  this.now = now
+  if (maxAge) this.maxAge = maxAge
+}
+
+})()