wavelength_server/websocket_server/node_modules/postgres-array/index.js

98 lines
2.3 KiB
JavaScript

'use strict'
exports.parse = function (source, transform) {
return new ArrayParser(source, transform).parse()
}
class ArrayParser {
constructor (source, transform) {
this.source = source
this.transform = transform || identity
this.position = 0
this.entries = []
this.recorded = []
this.dimension = 0
}
isEof () {
return this.position >= this.source.length
}
nextCharacter () {
var character = this.source[this.position++]
if (character === '\\') {
return {
value: this.source[this.position++],
escaped: true
}
}
return {
value: character,
escaped: false
}
}
record (character) {
this.recorded.push(character)
}
newEntry (includeEmpty) {
var entry
if (this.recorded.length > 0 || includeEmpty) {
entry = this.recorded.join('')
if (entry === 'NULL' && !includeEmpty) {
entry = null
}
if (entry !== null) entry = this.transform(entry)
this.entries.push(entry)
this.recorded = []
}
}
consumeDimensions () {
if (this.source[0] === '[') {
while (!this.isEof()) {
var char = this.nextCharacter()
if (char.value === '=') break
}
}
}
parse (nested) {
var character, parser, quote
this.consumeDimensions()
while (!this.isEof()) {
character = this.nextCharacter()
if (character.value === '{' && !quote) {
this.dimension++
if (this.dimension > 1) {
parser = new ArrayParser(this.source.substr(this.position - 1), this.transform)
this.entries.push(parser.parse(true))
this.position += parser.position - 2
}
} else if (character.value === '}' && !quote) {
this.dimension--
if (!this.dimension) {
this.newEntry()
if (nested) return this.entries
}
} else if (character.value === '"' && !character.escaped) {
if (quote) this.newEntry(true)
quote = !quote
} else if (character.value === ',' && !quote) {
this.newEntry()
} else {
this.record(character.value)
}
}
if (this.dimension !== 0) {
throw new Error('array dimension not balanced')
}
return this.entries
}
}
function identity (value) {
return value
}