Index: node_modules/postcss/lib/lazy-result.js
===================================================================
--- node_modules/postcss/lib/lazy-result.js	(revision 2058e5c694bb6097866a5fe6503c519e8f74970f)
+++ node_modules/postcss/lib/lazy-result.js	(revision 2058e5c694bb6097866a5fe6503c519e8f74970f)
@@ -0,0 +1,550 @@
+'use strict'
+
+let Container = require('./container')
+let Document = require('./document')
+let MapGenerator = require('./map-generator')
+let parse = require('./parse')
+let Result = require('./result')
+let Root = require('./root')
+let stringify = require('./stringify')
+let { isClean, my } = require('./symbols')
+let warnOnce = require('./warn-once')
+
+const TYPE_TO_CLASS_NAME = {
+  atrule: 'AtRule',
+  comment: 'Comment',
+  decl: 'Declaration',
+  document: 'Document',
+  root: 'Root',
+  rule: 'Rule'
+}
+
+const PLUGIN_PROPS = {
+  AtRule: true,
+  AtRuleExit: true,
+  Comment: true,
+  CommentExit: true,
+  Declaration: true,
+  DeclarationExit: true,
+  Document: true,
+  DocumentExit: true,
+  Once: true,
+  OnceExit: true,
+  postcssPlugin: true,
+  prepare: true,
+  Root: true,
+  RootExit: true,
+  Rule: true,
+  RuleExit: true
+}
+
+const NOT_VISITORS = {
+  Once: true,
+  postcssPlugin: true,
+  prepare: true
+}
+
+const CHILDREN = 0
+
+function isPromise(obj) {
+  return typeof obj === 'object' && typeof obj.then === 'function'
+}
+
+function getEvents(node) {
+  let key = false
+  let type = TYPE_TO_CLASS_NAME[node.type]
+  if (node.type === 'decl') {
+    key = node.prop.toLowerCase()
+  } else if (node.type === 'atrule') {
+    key = node.name.toLowerCase()
+  }
+
+  if (key && node.append) {
+    return [
+      type,
+      type + '-' + key,
+      CHILDREN,
+      type + 'Exit',
+      type + 'Exit-' + key
+    ]
+  } else if (key) {
+    return [type, type + '-' + key, type + 'Exit', type + 'Exit-' + key]
+  } else if (node.append) {
+    return [type, CHILDREN, type + 'Exit']
+  } else {
+    return [type, type + 'Exit']
+  }
+}
+
+function toStack(node) {
+  let events
+  if (node.type === 'document') {
+    events = ['Document', CHILDREN, 'DocumentExit']
+  } else if (node.type === 'root') {
+    events = ['Root', CHILDREN, 'RootExit']
+  } else {
+    events = getEvents(node)
+  }
+
+  return {
+    eventIndex: 0,
+    events,
+    iterator: 0,
+    node,
+    visitorIndex: 0,
+    visitors: []
+  }
+}
+
+function cleanMarks(node) {
+  node[isClean] = false
+  if (node.nodes) node.nodes.forEach(i => cleanMarks(i))
+  return node
+}
+
+let postcss = {}
+
+class LazyResult {
+  get content() {
+    return this.stringify().content
+  }
+
+  get css() {
+    return this.stringify().css
+  }
+
+  get map() {
+    return this.stringify().map
+  }
+
+  get messages() {
+    return this.sync().messages
+  }
+
+  get opts() {
+    return this.result.opts
+  }
+
+  get processor() {
+    return this.result.processor
+  }
+
+  get root() {
+    return this.sync().root
+  }
+
+  get [Symbol.toStringTag]() {
+    return 'LazyResult'
+  }
+
+  constructor(processor, css, opts) {
+    this.stringified = false
+    this.processed = false
+
+    let root
+    if (
+      typeof css === 'object' &&
+      css !== null &&
+      (css.type === 'root' || css.type === 'document')
+    ) {
+      root = cleanMarks(css)
+    } else if (css instanceof LazyResult || css instanceof Result) {
+      root = cleanMarks(css.root)
+      if (css.map) {
+        if (typeof opts.map === 'undefined') opts.map = {}
+        if (!opts.map.inline) opts.map.inline = false
+        opts.map.prev = css.map
+      }
+    } else {
+      let parser = parse
+      if (opts.syntax) parser = opts.syntax.parse
+      if (opts.parser) parser = opts.parser
+      if (parser.parse) parser = parser.parse
+
+      try {
+        root = parser(css, opts)
+      } catch (error) {
+        this.processed = true
+        this.error = error
+      }
+
+      if (root && !root[my]) {
+        /* c8 ignore next 2 */
+        Container.rebuild(root)
+      }
+    }
+
+    this.result = new Result(processor, root, opts)
+    this.helpers = { ...postcss, postcss, result: this.result }
+    this.plugins = this.processor.plugins.map(plugin => {
+      if (typeof plugin === 'object' && plugin.prepare) {
+        return { ...plugin, ...plugin.prepare(this.result) }
+      } else {
+        return plugin
+      }
+    })
+  }
+
+  async() {
+    if (this.error) return Promise.reject(this.error)
+    if (this.processed) return Promise.resolve(this.result)
+    if (!this.processing) {
+      this.processing = this.runAsync()
+    }
+    return this.processing
+  }
+
+  catch(onRejected) {
+    return this.async().catch(onRejected)
+  }
+
+  finally(onFinally) {
+    return this.async().then(onFinally, onFinally)
+  }
+
+  getAsyncError() {
+    throw new Error('Use process(css).then(cb) to work with async plugins')
+  }
+
+  handleError(error, node) {
+    let plugin = this.result.lastPlugin
+    try {
+      if (node) node.addToError(error)
+      this.error = error
+      if (error.name === 'CssSyntaxError' && !error.plugin) {
+        error.plugin = plugin.postcssPlugin
+        error.setMessage()
+      } else if (plugin.postcssVersion) {
+        if (process.env.NODE_ENV !== 'production') {
+          let pluginName = plugin.postcssPlugin
+          let pluginVer = plugin.postcssVersion
+          let runtimeVer = this.result.processor.version
+          let a = pluginVer.split('.')
+          let b = runtimeVer.split('.')
+
+          if (a[0] !== b[0] || parseInt(a[1]) > parseInt(b[1])) {
+            // eslint-disable-next-line no-console
+            console.error(
+              'Unknown error from PostCSS plugin. Your current PostCSS ' +
+                'version is ' +
+                runtimeVer +
+                ', but ' +
+                pluginName +
+                ' uses ' +
+                pluginVer +
+                '. Perhaps this is the source of the error below.'
+            )
+          }
+        }
+      }
+    } catch (err) {
+      /* c8 ignore next 3 */
+      // eslint-disable-next-line no-console
+      if (console && console.error) console.error(err)
+    }
+    return error
+  }
+
+  prepareVisitors() {
+    this.listeners = {}
+    let add = (plugin, type, cb) => {
+      if (!this.listeners[type]) this.listeners[type] = []
+      this.listeners[type].push([plugin, cb])
+    }
+    for (let plugin of this.plugins) {
+      if (typeof plugin === 'object') {
+        for (let event in plugin) {
+          if (!PLUGIN_PROPS[event] && /^[A-Z]/.test(event)) {
+            throw new Error(
+              `Unknown event ${event} in ${plugin.postcssPlugin}. ` +
+                `Try to update PostCSS (${this.processor.version} now).`
+            )
+          }
+          if (!NOT_VISITORS[event]) {
+            if (typeof plugin[event] === 'object') {
+              for (let filter in plugin[event]) {
+                if (filter === '*') {
+                  add(plugin, event, plugin[event][filter])
+                } else {
+                  add(
+                    plugin,
+                    event + '-' + filter.toLowerCase(),
+                    plugin[event][filter]
+                  )
+                }
+              }
+            } else if (typeof plugin[event] === 'function') {
+              add(plugin, event, plugin[event])
+            }
+          }
+        }
+      }
+    }
+    this.hasListener = Object.keys(this.listeners).length > 0
+  }
+
+  async runAsync() {
+    this.plugin = 0
+    for (let i = 0; i < this.plugins.length; i++) {
+      let plugin = this.plugins[i]
+      let promise = this.runOnRoot(plugin)
+      if (isPromise(promise)) {
+        try {
+          await promise
+        } catch (error) {
+          throw this.handleError(error)
+        }
+      }
+    }
+
+    this.prepareVisitors()
+    if (this.hasListener) {
+      let root = this.result.root
+      while (!root[isClean]) {
+        root[isClean] = true
+        let stack = [toStack(root)]
+        while (stack.length > 0) {
+          let promise = this.visitTick(stack)
+          if (isPromise(promise)) {
+            try {
+              await promise
+            } catch (e) {
+              let node = stack[stack.length - 1].node
+              throw this.handleError(e, node)
+            }
+          }
+        }
+      }
+
+      if (this.listeners.OnceExit) {
+        for (let [plugin, visitor] of this.listeners.OnceExit) {
+          this.result.lastPlugin = plugin
+          try {
+            if (root.type === 'document') {
+              let roots = root.nodes.map(subRoot =>
+                visitor(subRoot, this.helpers)
+              )
+
+              await Promise.all(roots)
+            } else {
+              await visitor(root, this.helpers)
+            }
+          } catch (e) {
+            throw this.handleError(e)
+          }
+        }
+      }
+    }
+
+    this.processed = true
+    return this.stringify()
+  }
+
+  runOnRoot(plugin) {
+    this.result.lastPlugin = plugin
+    try {
+      if (typeof plugin === 'object' && plugin.Once) {
+        if (this.result.root.type === 'document') {
+          let roots = this.result.root.nodes.map(root =>
+            plugin.Once(root, this.helpers)
+          )
+
+          if (isPromise(roots[0])) {
+            return Promise.all(roots)
+          }
+
+          return roots
+        }
+
+        return plugin.Once(this.result.root, this.helpers)
+      } else if (typeof plugin === 'function') {
+        return plugin(this.result.root, this.result)
+      }
+    } catch (error) {
+      throw this.handleError(error)
+    }
+  }
+
+  stringify() {
+    if (this.error) throw this.error
+    if (this.stringified) return this.result
+    this.stringified = true
+
+    this.sync()
+
+    let opts = this.result.opts
+    let str = stringify
+    if (opts.syntax) str = opts.syntax.stringify
+    if (opts.stringifier) str = opts.stringifier
+    if (str.stringify) str = str.stringify
+
+    let map = new MapGenerator(str, this.result.root, this.result.opts)
+    let data = map.generate()
+    this.result.css = data[0]
+    this.result.map = data[1]
+
+    return this.result
+  }
+
+  sync() {
+    if (this.error) throw this.error
+    if (this.processed) return this.result
+    this.processed = true
+
+    if (this.processing) {
+      throw this.getAsyncError()
+    }
+
+    for (let plugin of this.plugins) {
+      let promise = this.runOnRoot(plugin)
+      if (isPromise(promise)) {
+        throw this.getAsyncError()
+      }
+    }
+
+    this.prepareVisitors()
+    if (this.hasListener) {
+      let root = this.result.root
+      while (!root[isClean]) {
+        root[isClean] = true
+        this.walkSync(root)
+      }
+      if (this.listeners.OnceExit) {
+        if (root.type === 'document') {
+          for (let subRoot of root.nodes) {
+            this.visitSync(this.listeners.OnceExit, subRoot)
+          }
+        } else {
+          this.visitSync(this.listeners.OnceExit, root)
+        }
+      }
+    }
+
+    return this.result
+  }
+
+  then(onFulfilled, onRejected) {
+    if (process.env.NODE_ENV !== 'production') {
+      if (!('from' in this.opts)) {
+        warnOnce(
+          'Without `from` option PostCSS could generate wrong source map ' +
+            'and will not find Browserslist config. Set it to CSS file path ' +
+            'or to `undefined` to prevent this warning.'
+        )
+      }
+    }
+    return this.async().then(onFulfilled, onRejected)
+  }
+
+  toString() {
+    return this.css
+  }
+
+  visitSync(visitors, node) {
+    for (let [plugin, visitor] of visitors) {
+      this.result.lastPlugin = plugin
+      let promise
+      try {
+        promise = visitor(node, this.helpers)
+      } catch (e) {
+        throw this.handleError(e, node.proxyOf)
+      }
+      if (node.type !== 'root' && node.type !== 'document' && !node.parent) {
+        return true
+      }
+      if (isPromise(promise)) {
+        throw this.getAsyncError()
+      }
+    }
+  }
+
+  visitTick(stack) {
+    let visit = stack[stack.length - 1]
+    let { node, visitors } = visit
+
+    if (node.type !== 'root' && node.type !== 'document' && !node.parent) {
+      stack.pop()
+      return
+    }
+
+    if (visitors.length > 0 && visit.visitorIndex < visitors.length) {
+      let [plugin, visitor] = visitors[visit.visitorIndex]
+      visit.visitorIndex += 1
+      if (visit.visitorIndex === visitors.length) {
+        visit.visitors = []
+        visit.visitorIndex = 0
+      }
+      this.result.lastPlugin = plugin
+      try {
+        return visitor(node.toProxy(), this.helpers)
+      } catch (e) {
+        throw this.handleError(e, node)
+      }
+    }
+
+    if (visit.iterator !== 0) {
+      let iterator = visit.iterator
+      let child
+      while ((child = node.nodes[node.indexes[iterator]])) {
+        node.indexes[iterator] += 1
+        if (!child[isClean]) {
+          child[isClean] = true
+          stack.push(toStack(child))
+          return
+        }
+      }
+      visit.iterator = 0
+      delete node.indexes[iterator]
+    }
+
+    let events = visit.events
+    while (visit.eventIndex < events.length) {
+      let event = events[visit.eventIndex]
+      visit.eventIndex += 1
+      if (event === CHILDREN) {
+        if (node.nodes && node.nodes.length) {
+          node[isClean] = true
+          visit.iterator = node.getIterator()
+        }
+        return
+      } else if (this.listeners[event]) {
+        visit.visitors = this.listeners[event]
+        return
+      }
+    }
+    stack.pop()
+  }
+
+  walkSync(node) {
+    node[isClean] = true
+    let events = getEvents(node)
+    for (let event of events) {
+      if (event === CHILDREN) {
+        if (node.nodes) {
+          node.each(child => {
+            if (!child[isClean]) this.walkSync(child)
+          })
+        }
+      } else {
+        let visitors = this.listeners[event]
+        if (visitors) {
+          if (this.visitSync(visitors, node.toProxy())) return
+        }
+      }
+    }
+  }
+
+  warnings() {
+    return this.sync().warnings()
+  }
+}
+
+LazyResult.registerPostcss = dependant => {
+  postcss = dependant
+}
+
+module.exports = LazyResult
+LazyResult.default = LazyResult
+
+Root.registerLazyResult(LazyResult)
+Document.registerLazyResult(LazyResult)