File: /var/www/javago-nodeserver-hotfixes/node_modules/lru.min/lib/index.js
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.createLRU = void 0;
const createLRU = (options) => {
let { max, onEviction } = options;
if (!(Number.isInteger(max) && max > 0))
throw new TypeError('`max` must be a positive integer');
let size = 0;
let head = 0;
let tail = 0;
let free = [];
const keyMap = new Map();
const keyList = new Array(max).fill(undefined);
const valList = new Array(max).fill(undefined);
const next = new Array(max).fill(0);
const prev = new Array(max).fill(0);
const setTail = (index, type) => {
if (index === tail)
return;
const nextIndex = next[index];
const prevIndex = prev[index];
if (index === head)
head = nextIndex;
else if (type === 'get' || prevIndex !== 0)
next[prevIndex] = nextIndex;
if (nextIndex !== 0)
prev[nextIndex] = prevIndex;
next[tail] = index;
prev[index] = tail;
next[index] = 0;
tail = index;
};
const _evict = () => {
const evictHead = head;
const key = keyList[evictHead];
onEviction === null || onEviction === void 0 ? void 0 : onEviction(key, valList[evictHead]);
keyMap.delete(key);
keyList[evictHead] = undefined;
valList[evictHead] = undefined;
head = next[evictHead];
if (head !== 0)
prev[head] = 0;
size--;
if (size === 0)
head = tail = 0;
free.push(evictHead);
return evictHead;
};
return {
/** Adds a key-value pair to the cache. Updates the value if the key already exists. */
set(key, value) {
if (key === undefined)
return;
let index = keyMap.get(key);
if (index === undefined) {
index = size === max ? _evict() : free.length > 0 ? free.pop() : size;
keyMap.set(key, index);
keyList[index] = key;
size++;
}
else
onEviction === null || onEviction === void 0 ? void 0 : onEviction(key, valList[index]);
valList[index] = value;
if (size === 1)
head = tail = index;
else
setTail(index, 'set');
},
/** Retrieves the value for a given key and moves the key to the most recent position. */
get(key) {
const index = keyMap.get(key);
if (index === undefined)
return;
if (index !== tail)
setTail(index, 'get');
return valList[index];
},
/** Retrieves the value for a given key without changing its position. */
peek: (key) => {
const index = keyMap.get(key);
return index !== undefined ? valList[index] : undefined;
},
/** Checks if a key exists in the cache. */
has: (key) => keyMap.has(key),
/** Iterates over all keys in the cache, from most recent to least recent. */
*keys() {
let current = tail;
for (let i = 0; i < size; i++) {
yield keyList[current];
current = prev[current];
}
},
/** Iterates over all values in the cache, from most recent to least recent. */
*values() {
let current = tail;
for (let i = 0; i < size; i++) {
yield valList[current];
current = prev[current];
}
},
/** Iterates over `[key, value]` pairs in the cache, from most recent to least recent. */
*entries() {
let current = tail;
for (let i = 0; i < size; i++) {
yield [keyList[current], valList[current]];
current = prev[current];
}
},
/** Iterates over each value-key pair in the cache, from most recent to least recent. */
forEach: (callback) => {
let current = tail;
for (let i = 0; i < size; i++) {
const key = keyList[current];
const value = valList[current];
callback(value, key);
current = prev[current];
}
},
/** Deletes a key-value pair from the cache. */
delete(key) {
const index = keyMap.get(key);
if (index === undefined)
return false;
onEviction === null || onEviction === void 0 ? void 0 : onEviction(key, valList[index]);
keyMap.delete(key);
free.push(index);
keyList[index] = undefined;
valList[index] = undefined;
const prevIndex = prev[index];
const nextIndex = next[index];
if (prevIndex !== 0)
next[prevIndex] = nextIndex;
if (nextIndex !== 0)
prev[nextIndex] = prevIndex;
if (index === head)
head = nextIndex;
if (index === tail)
tail = prevIndex;
size--;
return true;
},
/** Evicts the oldest item or the specified number of the oldest items from the cache. */
evict: (number) => {
let toPrune = Math.min(number, size);
while (toPrune > 0) {
_evict();
toPrune--;
}
},
/** Clears all key-value pairs from the cache. */
clear() {
if (typeof onEviction === 'function') {
const iterator = keyMap.values();
for (let result = iterator.next(); !result.done; result = iterator.next())
onEviction(keyList[result.value], valList[result.value]);
}
keyMap.clear();
keyList.fill(undefined);
valList.fill(undefined);
free = [];
size = 0;
head = tail = 0;
},
/** Resizes the cache to a new maximum size, evicting items if necessary. */
resize: (newMax) => {
if (!(Number.isInteger(newMax) && newMax > 0))
throw new TypeError('`max` must be a positive integer');
if (newMax === max)
return;
if (newMax < max) {
let current = tail;
const preserve = Math.min(size, newMax);
const remove = size - preserve;
const newKeyList = new Array(newMax);
const newValList = new Array(newMax);
const newNext = new Array(newMax);
const newPrev = new Array(newMax);
for (let i = 1; i <= remove; i++)
onEviction === null || onEviction === void 0 ? void 0 : onEviction(keyList[i], valList[i]);
for (let i = preserve - 1; i >= 0; i--) {
newKeyList[i] = keyList[current];
newValList[i] = valList[current];
newNext[i] = i + 1;
newPrev[i] = i - 1;
keyMap.set(newKeyList[i], i);
current = prev[current];
}
head = 0;
tail = preserve - 1;
size = preserve;
keyList.length = newMax;
valList.length = newMax;
next.length = newMax;
prev.length = newMax;
for (let i = 0; i < preserve; i++) {
keyList[i] = newKeyList[i];
valList[i] = newValList[i];
next[i] = newNext[i];
prev[i] = newPrev[i];
}
free = [];
for (let i = preserve; i < newMax; i++)
free.push(i);
}
else {
const fill = newMax - max;
keyList.push(...new Array(fill).fill(undefined));
valList.push(...new Array(fill).fill(undefined));
next.push(...new Array(fill).fill(0));
prev.push(...new Array(fill).fill(0));
}
max = newMax;
},
/** Returns the maximum number of items that can be stored in the cache. */
get max() {
return max;
},
/** Returns the number of items currently stored in the cache. */
get size() {
return size;
},
/** Returns the number of currently available slots in the cache before reaching the maximum size. */
get available() {
return max - size;
},
};
};
exports.createLRU = createLRU;