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diff --git a/deps/npm/node_modules/cacache/node_modules/lru-cache/index.js b/deps/npm/node_modules/cacache/node_modules/lru-cache/index.js
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+'use strict'
+
+// A linked list to keep track of recently-used-ness
+const Yallist = require('yallist')
+
+const MAX = Symbol('max')
+const LENGTH = Symbol('length')
+const LENGTH_CALCULATOR = Symbol('lengthCalculator')
+const ALLOW_STALE = Symbol('allowStale')
+const MAX_AGE = Symbol('maxAge')
+const DISPOSE = Symbol('dispose')
+const NO_DISPOSE_ON_SET = Symbol('noDisposeOnSet')
+const LRU_LIST = Symbol('lruList')
+const CACHE = Symbol('cache')
+const UPDATE_AGE_ON_GET = Symbol('updateAgeOnGet')
+
+const naiveLength = () => 1
+
+// lruList is a yallist where the head is the youngest
+// item, and the tail is the oldest. the list contains the Hit
+// objects as the entries.
+// Each Hit object has a reference to its Yallist.Node. This
+// never changes.
+//
+// cache is a Map (or PseudoMap) that matches the keys to
+// the Yallist.Node object.
+class LRUCache {
+ constructor (options) {
+ if (typeof options === 'number')
+ options = { max: options }
+
+ if (!options)
+ options = {}
+
+ if (options.max && (typeof options.max !== 'number' || options.max < 0))
+ throw new TypeError('max must be a non-negative number')
+ // Kind of weird to have a default max of Infinity, but oh well.
+ const max = this[MAX] = options.max || Infinity
+
+ const lc = options.length || naiveLength
+ this[LENGTH_CALCULATOR] = (typeof lc !== 'function') ? naiveLength : lc
+ this[ALLOW_STALE] = options.stale || false
+ if (options.maxAge && typeof options.maxAge !== 'number')
+ throw new TypeError('maxAge must be a number')
+ this[MAX_AGE] = options.maxAge || 0
+ this[DISPOSE] = options.dispose
+ this[NO_DISPOSE_ON_SET] = options.noDisposeOnSet || false
+ this[UPDATE_AGE_ON_GET] = options.updateAgeOnGet || false
+ this.reset()
+ }
+
+ // resize the cache when the max changes.
+ set max (mL) {
+ if (typeof mL !== 'number' || mL < 0)
+ throw new TypeError('max must be a non-negative number')
+
+ this[MAX] = mL || Infinity
+ trim(this)
+ }
+ get max () {
+ return this[MAX]
+ }
+
+ set allowStale (allowStale) {
+ this[ALLOW_STALE] = !!allowStale
+ }
+ get allowStale () {
+ return this[ALLOW_STALE]
+ }
+
+ set maxAge (mA) {
+ if (typeof mA !== 'number')
+ throw new TypeError('maxAge must be a non-negative number')
+
+ this[MAX_AGE] = mA
+ trim(this)
+ }
+ get maxAge () {
+ return this[MAX_AGE]
+ }
+
+ // resize the cache when the lengthCalculator changes.
+ set lengthCalculator (lC) {
+ if (typeof lC !== 'function')
+ lC = naiveLength
+
+ if (lC !== this[LENGTH_CALCULATOR]) {
+ this[LENGTH_CALCULATOR] = lC
+ this[LENGTH] = 0
+ this[LRU_LIST].forEach(hit => {
+ hit.length = this[LENGTH_CALCULATOR](hit.value, hit.key)
+ this[LENGTH] += hit.length
+ })
+ }
+ trim(this)
+ }
+ get lengthCalculator () { return this[LENGTH_CALCULATOR] }
+
+ get length () { return this[LENGTH] }
+ get itemCount () { return this[LRU_LIST].length }
+
+ rforEach (fn, thisp) {
+ thisp = thisp || this
+ for (let walker = this[LRU_LIST].tail; walker !== null;) {
+ const prev = walker.prev
+ forEachStep(this, fn, walker, thisp)
+ walker = prev
+ }
+ }
+
+ forEach (fn, thisp) {
+ thisp = thisp || this
+ for (let walker = this[LRU_LIST].head; walker !== null;) {
+ const next = walker.next
+ forEachStep(this, fn, walker, thisp)
+ walker = next
+ }
+ }
+
+ keys () {
+ return this[LRU_LIST].toArray().map(k => k.key)
+ }
+
+ values () {
+ return this[LRU_LIST].toArray().map(k => k.value)
+ }
+
+ reset () {
+ if (this[DISPOSE] &&
+ this[LRU_LIST] &&
+ this[LRU_LIST].length) {
+ this[LRU_LIST].forEach(hit => this[DISPOSE](hit.key, hit.value))
+ }
+
+ this[CACHE] = new Map() // hash of items by key
+ this[LRU_LIST] = new Yallist() // list of items in order of use recency
+ this[LENGTH] = 0 // length of items in the list
+ }
+
+ dump () {
+ return this[LRU_LIST].map(hit =>
+ isStale(this, hit) ? false : {
+ k: hit.key,
+ v: hit.value,
+ e: hit.now + (hit.maxAge || 0)
+ }).toArray().filter(h => h)
+ }
+
+ dumpLru () {
+ return this[LRU_LIST]
+ }
+
+ set (key, value, maxAge) {
+ maxAge = maxAge || this[MAX_AGE]
+
+ if (maxAge && typeof maxAge !== 'number')
+ throw new TypeError('maxAge must be a number')
+
+ const now = maxAge ? Date.now() : 0
+ const len = this[LENGTH_CALCULATOR](value, key)
+
+ if (this[CACHE].has(key)) {
+ if (len > this[MAX]) {
+ del(this, this[CACHE].get(key))
+ return false
+ }
+
+ const node = this[CACHE].get(key)
+ const item = node.value
+
+ // dispose of the old one before overwriting
+ // split out into 2 ifs for better coverage tracking
+ if (this[DISPOSE]) {
+ if (!this[NO_DISPOSE_ON_SET])
+ this[DISPOSE](key, item.value)
+ }
+
+ item.now = now
+ item.maxAge = maxAge
+ item.value = value
+ this[LENGTH] += len - item.length
+ item.length = len
+ this.get(key)
+ trim(this)
+ return true
+ }
+
+ const hit = new Entry(key, value, 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[LRU_LIST].unshift(hit)
+ this[CACHE].set(key, this[LRU_LIST].head)
+ trim(this)
+ return true
+ }
+
+ has (key) {
+ if (!this[CACHE].has(key)) return false
+ const hit = this[CACHE].get(key).value
+ return !isStale(this, hit)
+ }
+
+ get (key) {
+ return get(this, key, true)
+ }
+
+ peek (key) {
+ return get(this, key, false)
+ }
+
+ pop () {
+ const node = this[LRU_LIST].tail
+ if (!node)
+ return null
+
+ del(this, node)
+ return node.value
+ }
+
+ del (key) {
+ del(this, this[CACHE].get(key))
+ }
+
+ load (arr) {
+ // reset the cache
+ this.reset()
+
+ const now = Date.now()
+ // A previous serialized cache has the most recent items first
+ for (let l = arr.length - 1; l >= 0; l--) {
+ const hit = arr[l]
+ const 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 {
+ const maxAge = expiresAt - now
+ // dont add already expired items
+ if (maxAge > 0) {
+ this.set(hit.k, hit.v, maxAge)
+ }
+ }
+ }
+ }
+
+ prune () {
+ this[CACHE].forEach((value, key) => get(this, key, false))
+ }
+}
+
+const get = (self, key, doUse) => {
+ const node = self[CACHE].get(key)
+ if (node) {
+ const hit = node.value
+ if (isStale(self, hit)) {
+ del(self, node)
+ if (!self[ALLOW_STALE])
+ return undefined
+ } else {
+ if (doUse) {
+ if (self[UPDATE_AGE_ON_GET])
+ node.value.now = Date.now()
+ self[LRU_LIST].unshiftNode(node)
+ }
+ }
+ return hit.value
+ }
+}
+
+const isStale = (self, hit) => {
+ if (!hit || (!hit.maxAge && !self[MAX_AGE]))
+ return false
+
+ const diff = Date.now() - hit.now
+ return hit.maxAge ? diff > hit.maxAge
+ : self[MAX_AGE] && (diff > self[MAX_AGE])
+}
+
+const trim = self => {
+ if (self[LENGTH] > self[MAX]) {
+ for (let walker = self[LRU_LIST].tail;
+ self[LENGTH] > self[MAX] && walker !== null;) {
+ // We know that we're about to delete this one, and also
+ // what the next least recently used key will be, so just
+ // go ahead and set it now.
+ const prev = walker.prev
+ del(self, walker)
+ walker = prev
+ }
+ }
+}
+
+const del = (self, node) => {
+ if (node) {
+ const hit = node.value
+ if (self[DISPOSE])
+ self[DISPOSE](hit.key, hit.value)
+
+ self[LENGTH] -= hit.length
+ self[CACHE].delete(hit.key)
+ self[LRU_LIST].removeNode(node)
+ }
+}
+
+class Entry {
+ constructor (key, value, length, now, maxAge) {
+ this.key = key
+ this.value = value
+ this.length = length
+ this.now = now
+ this.maxAge = maxAge || 0
+ }
+}
+
+const forEachStep = (self, fn, node, thisp) => {
+ let hit = node.value
+ if (isStale(self, hit)) {
+ del(self, node)
+ if (!self[ALLOW_STALE])
+ hit = undefined
+ }
+ if (hit)
+ fn.call(thisp, hit.value, hit.key, self)
+}
+
+module.exports = LRUCache