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Tool for transforming styles with JS plugins
'use strict'
let Declaration = require('./declaration')
let tokenizer = require('./tokenize')
let Comment = require('./comment')
let AtRule = require('./at-rule')
let Root = require('./root')
let Rule = require('./rule')
const SAFE_COMMENT_NEIGHBOR = {
empty: true,
space: true
}
function findLastWithPosition(tokens) {
for (let i = tokens.length - 1; i >= 0; i--) {
let token = tokens[i]
let pos = token[3] || token[2]
if (pos) return pos
}
}
class Parser {
constructor(input) {
this.input = input
this.root = new Root()
this.current = this.root
this.spaces = ''
this.semicolon = false
this.createTokenizer()
this.root.source = { input, start: { column: 1, line: 1, offset: 0 } }
}
atrule(token) {
let node = new AtRule()
node.name = token[1].slice(1)
if (node.name === '') {
this.unnamedAtrule(node, token)
}
this.init(node, token[2])
let type
let prev
let shift
let last = false
let open = false
let params = []
let brackets = []
while (!this.tokenizer.endOfFile()) {
token = this.tokenizer.nextToken()
type = token[0]
if (type === '(' || type === '[') {
brackets.push(type === '(' ? ')' : ']')
} else if (type === '{' && brackets.length > 0) {
brackets.push('}')
} else if (type === brackets[brackets.length - 1]) {
brackets.pop()
}
if (brackets.length === 0) {
if (type === ';') {
node.source.end = this.getPosition(token[2])
node.source.end.offset++
this.semicolon = true
break
} else if (type === '{') {
open = true
break
} else if (type === '}') {
if (params.length > 0) {
shift = params.length - 1
prev = params[shift]
while (prev && prev[0] === 'space') {
prev = params[--shift]
}
if (prev) {
node.source.end = this.getPosition(prev[3] || prev[2])
node.source.end.offset++
}
}
this.end(token)
break
} else {
params.push(token)
}
} else {
params.push(token)
}
if (this.tokenizer.endOfFile()) {
last = true
break
}
}
node.raws.between = this.spacesAndCommentsFromEnd(params)
if (params.length) {
node.raws.afterName = this.spacesAndCommentsFromStart(params)
this.raw(node, 'params', params)
if (last) {
token = params[params.length - 1]
node.source.end = this.getPosition(token[3] || token[2])
node.source.end.offset++
this.spaces = node.raws.between
node.raws.between = ''
}
} else {
node.raws.afterName = ''
node.params = ''
}
if (open) {
node.nodes = []
this.current = node
}
}
checkMissedSemicolon(tokens) {
let colon = this.colon(tokens)
if (colon === false) return
let founded = 0
let token
for (let j = colon - 1; j >= 0; j--) {
token = tokens[j]
if (token[0] !== 'space') {
founded += 1
if (founded === 2) break
}
}
// If the token is a word, e.g. `!important`, `red` or any other valid property's value.
// Then we need to return the colon after that word token. [3] is the "end" colon of that word.
// And because we need it after that one we do +1 to get the next one.
throw this.input.error(
'Missed semicolon',
token[0] === 'word' ? token[3] + 1 : token[2]
)
}
colon(tokens) {
let brackets = 0
let token, type, prev
for (let [i, element] of tokens.entries()) {
token = element
type = token[0]
if (type === '(') {
brackets += 1
}
if (type === ')') {
brackets -= 1
}
if (brackets === 0 && type === ':') {
if (!prev) {
this.doubleColon(token)
} else if (prev[0] === 'word' && prev[1] === 'progid') {
continue
} else {
return i
}
}
prev = token
}
return false
}
comment(token) {
let node = new Comment()
this.init(node, token[2])
node.source.end = this.getPosition(token[3] || token[2])
node.source.end.offset++
let text = token[1].slice(2, -2)
if (/^\s*$/.test(text)) {
node.text = ''
node.raws.left = text
node.raws.right = ''
} else {
let match = text.match(/^(\s*)([^]*\S)(\s*)$/)
node.text = match[2]
node.raws.left = match[1]
node.raws.right = match[3]
}
}
createTokenizer() {
this.tokenizer = tokenizer(this.input)
}
decl(tokens, customProperty) {
let node = new Declaration()
this.init(node, tokens[0][2])
let last = tokens[tokens.length - 1]
if (last[0] === ';') {
this.semicolon = true
tokens.pop()
}
node.source.end = this.getPosition(
last[3] || last[2] || findLastWithPosition(tokens)
)
node.source.end.offset++
while (tokens[0][0] !== 'word') {
if (tokens.length === 1) this.unknownWord(tokens)
node.raws.before += tokens.shift()[1]
}
node.source.start = this.getPosition(tokens[0][2])
node.prop = ''
while (tokens.length) {
let type = tokens[0][0]
if (type === ':' || type === 'space' || type === 'comment') {
break
}
node.prop += tokens.shift()[1]
}
node.raws.between = ''
let token
while (tokens.length) {
token = tokens.shift()
if (token[0] === ':') {
node.raws.between += token[1]
break
} else {
if (token[0] === 'word' && /\w/.test(token[1])) {
this.unknownWord([token])
}
node.raws.between += token[1]
}
}
if (node.prop[0] === '_' || node.prop[0] === '*') {
node.raws.before += node.prop[0]
node.prop = node.prop.slice(1)
}
let firstSpaces = []
let next
while (tokens.length) {
next = tokens[0][0]
if (next !== 'space' && next !== 'comment') break
firstSpaces.push(tokens.shift())
}
this.precheckMissedSemicolon(tokens)
for (let i = tokens.length - 1; i >= 0; i--) {
token = tokens[i]
if (token[1].toLowerCase() === '!important') {
node.important = true
let string = this.stringFrom(tokens, i)
string = this.spacesFromEnd(tokens) + string
if (string !== ' !important') node.raws.important = string
break
} else if (token[1].toLowerCase() === 'important') {
let cache = tokens.slice(0)
let str = ''
for (let j = i; j > 0; j--) {
let type = cache[j][0]
if (str.trim().indexOf('!') === 0 && type !== 'space') {
break
}
str = cache.pop()[1] + str
}
if (str.trim().indexOf('!') === 0) {
node.important = true
node.raws.important = str
tokens = cache
}
}
if (token[0] !== 'space' && token[0] !== 'comment') {
break
}
}
let hasWord = tokens.some(i => i[0] !== 'space' && i[0] !== 'comment')
if (hasWord) {
node.raws.between += firstSpaces.map(i => i[1]).join('')
firstSpaces = []
}
this.raw(node, 'value', firstSpaces.concat(tokens), customProperty)
if (node.value.includes(':') && !customProperty) {
this.checkMissedSemicolon(tokens)
}
}
doubleColon(token) {
throw this.input.error(
'Double colon',
{ offset: token[2] },
{ offset: token[2] + token[1].length }
)
}
emptyRule(token) {
let node = new Rule()
this.init(node, token[2])
node.selector = ''
node.raws.between = ''
this.current = node
}
end(token) {
if (this.current.nodes && this.current.nodes.length) {
this.current.raws.semicolon = this.semicolon
}
this.semicolon = false
this.current.raws.after = (this.current.raws.after || '') + this.spaces
this.spaces = ''
if (this.current.parent) {
this.current.source.end = this.getPosition(token[2])
this.current.source.end.offset++
this.current = this.current.parent
} else {
this.unexpectedClose(token)
}
}
endFile() {
if (this.current.parent) this.unclosedBlock()
if (this.current.nodes && this.current.nodes.length) {
this.current.raws.semicolon = this.semicolon
}
this.current.raws.after = (this.current.raws.after || '') + this.spaces
this.root.source.end = this.getPosition(this.tokenizer.position())
}
freeSemicolon(token) {
this.spaces += token[1]
if (this.current.nodes) {
let prev = this.current.nodes[this.current.nodes.length - 1]
if (prev && prev.type === 'rule' && !prev.raws.ownSemicolon) {
prev.raws.ownSemicolon = this.spaces
this.spaces = ''
}
}
}
// Helpers
getPosition(offset) {
let pos = this.input.fromOffset(offset)
return {
column: pos.col,
line: pos.line,
offset
}
}
init(node, offset) {
this.current.push(node)
node.source = {
input: this.input,
start: this.getPosition(offset)
}
node.raws.before = this.spaces
this.spaces = ''
if (node.type !== 'comment') this.semicolon = false
}
other(start) {
let end = false
let type = null
let colon = false
let bracket = null
let brackets = []
let customProperty = start[1].startsWith('--')
let tokens = []
let token = start
while (token) {
type = token[0]
tokens.push(token)
if (type === '(' || type === '[') {
if (!bracket) bracket = token
brackets.push(type === '(' ? ')' : ']')
} else if (customProperty && colon && type === '{') {
if (!bracket) bracket = token
brackets.push('}')
} else if (brackets.length === 0) {
if (type === ';') {
if (colon) {
this.decl(tokens, customProperty)
return
} else {
break
}
} else if (type === '{') {
this.rule(tokens)
return
} else if (type === '}') {
this.tokenizer.back(tokens.pop())
end = true
break
} else if (type === ':') {
colon = true
}
} else if (type === brackets[brackets.length - 1]) {
brackets.pop()
if (brackets.length === 0) bracket = null
}
token = this.tokenizer.nextToken()
}
if (this.tokenizer.endOfFile()) end = true
if (brackets.length > 0) this.unclosedBracket(bracket)
if (end && colon) {
if (!customProperty) {
while (tokens.length) {
token = tokens[tokens.length - 1][0]
if (token !== 'space' && token !== 'comment') break
this.tokenizer.back(tokens.pop())
}
}
this.decl(tokens, customProperty)
} else {
this.unknownWord(tokens)
}
}
parse() {
let token
while (!this.tokenizer.endOfFile()) {
token = this.tokenizer.nextToken()
switch (token[0]) {
case 'space':
this.spaces += token[1]
break
case ';':
this.freeSemicolon(token)
break
case '}':
this.end(token)
break
case 'comment':
this.comment(token)
break
case 'at-word':
this.atrule(token)
break
case '{':
this.emptyRule(token)
break
default:
this.other(token)
break
}
}
this.endFile()
}
precheckMissedSemicolon(/* tokens */) {
// Hook for Safe Parser
}
raw(node, prop, tokens, customProperty) {
let token, type
let length = tokens.length
let value = ''
let clean = true
let next, prev
for (let i = 0; i < length; i += 1) {
token = tokens[i]
type = token[0]
if (type === 'space' && i === length - 1 && !customProperty) {
clean = false
} else if (type === 'comment') {
prev = tokens[i - 1] ? tokens[i - 1][0] : 'empty'
next = tokens[i + 1] ? tokens[i + 1][0] : 'empty'
if (!SAFE_COMMENT_NEIGHBOR[prev] && !SAFE_COMMENT_NEIGHBOR[next]) {
if (value.slice(-1) === ',') {
clean = false
} else {
value += token[1]
}
} else {
clean = false
}
} else {
value += token[1]
}
}
if (!clean) {
let raw = tokens.reduce((all, i) => all + i[1], '')
node.raws[prop] = { raw, value }
}
node[prop] = value
}
rule(tokens) {
tokens.pop()
let node = new Rule()
this.init(node, tokens[0][2])
node.raws.between = this.spacesAndCommentsFromEnd(tokens)
this.raw(node, 'selector', tokens)
this.current = node
}
spacesAndCommentsFromEnd(tokens) {
let lastTokenType
let spaces = ''
while (tokens.length) {
lastTokenType = tokens[tokens.length - 1][0]
if (lastTokenType !== 'space' && lastTokenType !== 'comment') break
spaces = tokens.pop()[1] + spaces
}
return spaces
}
// Errors
spacesAndCommentsFromStart(tokens) {
let next
let spaces = ''
while (tokens.length) {
next = tokens[0][0]
if (next !== 'space' && next !== 'comment') break
spaces += tokens.shift()[1]
}
return spaces
}
spacesFromEnd(tokens) {
let lastTokenType
let spaces = ''
while (tokens.length) {
lastTokenType = tokens[tokens.length - 1][0]
if (lastTokenType !== 'space') break
spaces = tokens.pop()[1] + spaces
}
return spaces
}
stringFrom(tokens, from) {
let result = ''
for (let i = from; i < tokens.length; i++) {
result += tokens[i][1]
}
tokens.splice(from, tokens.length - from)
return result
}
unclosedBlock() {
let pos = this.current.source.start
throw this.input.error('Unclosed block', pos.line, pos.column)
}
unclosedBracket(bracket) {
throw this.input.error(
'Unclosed bracket',
{ offset: bracket[2] },
{ offset: bracket[2] + 1 }
)
}
unexpectedClose(token) {
throw this.input.error(
'Unexpected }',
{ offset: token[2] },
{ offset: token[2] + 1 }
)
}
unknownWord(tokens) {
throw this.input.error(
'Unknown word',
{ offset: tokens[0][2] },
{ offset: tokens[0][2] + tokens[0][1].length }
)
}
unnamedAtrule(node, token) {
throw this.input.error(
'At-rule without name',
{ offset: token[2] },
{ offset: token[2] + token[1].length }
)
}
}
module.exports = Parser
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