securityos/node_modules/lunr/lib/token_set_builder.js

70 lines
1.6 KiB
JavaScript

lunr.TokenSet.Builder = function () {
this.previousWord = ""
this.root = new lunr.TokenSet
this.uncheckedNodes = []
this.minimizedNodes = {}
}
lunr.TokenSet.Builder.prototype.insert = function (word) {
var node,
commonPrefix = 0
if (word < this.previousWord) {
throw new Error ("Out of order word insertion")
}
for (var i = 0; i < word.length && i < this.previousWord.length; i++) {
if (word[i] != this.previousWord[i]) break
commonPrefix++
}
this.minimize(commonPrefix)
if (this.uncheckedNodes.length == 0) {
node = this.root
} else {
node = this.uncheckedNodes[this.uncheckedNodes.length - 1].child
}
for (var i = commonPrefix; i < word.length; i++) {
var nextNode = new lunr.TokenSet,
char = word[i]
node.edges[char] = nextNode
this.uncheckedNodes.push({
parent: node,
char: char,
child: nextNode
})
node = nextNode
}
node.final = true
this.previousWord = word
}
lunr.TokenSet.Builder.prototype.finish = function () {
this.minimize(0)
}
lunr.TokenSet.Builder.prototype.minimize = function (downTo) {
for (var i = this.uncheckedNodes.length - 1; i >= downTo; i--) {
var node = this.uncheckedNodes[i],
childKey = node.child.toString()
if (childKey in this.minimizedNodes) {
node.parent.edges[node.char] = this.minimizedNodes[childKey]
} else {
// Cache the key for this node since
// we know it can't change anymore
node.child._str = childKey
this.minimizedNodes[childKey] = node.child
}
this.uncheckedNodes.pop()
}
}