代码大概8600-10000

//动画结束后执行回调
function callPendingCbs (c) {
  /* istanbul ignore if */
  if (c.elm._moveCb) {
    c.elm._moveCb();
  }
  /* istanbul ignore if */
  if (c.elm._enterCb) {
    c.elm._enterCb();
  }
}

function recordPosition (c) {
  c.data.newPos = c.elm.getBoundingClientRect();
}
// 执行transition
function applyTranslation (c) {
  var oldPos = c.data.pos;
  var newPos = c.data.newPos;
  var dx = oldPos.left - newPos.left;
  var dy = oldPos.top - newPos.top;
  if (dx || dy) {
    c.data.moved = true;
    var s = c.elm.style;
    s.transform = s.WebkitTransform = "translate(" + dx + "px," + dy + "px)";
    s.transitionDuration = '0s';
  }
}

var platformComponents = {
  Transition: Transition,
  TransitionGroup: TransitionGroup
}

/*  */

// install platform specific utils
Vue.config.mustUseProp = mustUseProp;
Vue.config.isReservedTag = isReservedTag;
Vue.config.isReservedAttr = isReservedAttr;
Vue.config.getTagNamespace = getTagNamespace;
Vue.config.isUnknownElement = isUnknownElement;

// install platform runtime directives & components
extend(Vue.options.directives, platformDirectives);
extend(Vue.options.components, platformComponents);

// install platform patch function
Vue.prototype.__patch__ = inBrowser ? patch : noop;

// public mount method
// $mount vue的共用方法
Vue.prototype.$mount = function (
  el,
  hydrating
) {
  el = el && inBrowser ? query(el) : undefined;
  return mountComponent(this, el, hydrating)
};

// devtools global hook
/* istanbul ignore next */
if (inBrowser) {
  setTimeout(function () {
    if (config.devtools) {
      if (devtools) {
        devtools.emit('init', Vue);
      } else if (
        "development" !== 'production' &&
        "development" !== 'test' &&
        isChrome
      ) {
        console[console.info ? 'info' : 'log'](
          'Download the Vue Devtools extension for a better development experience:\n' +
          'https://github.com/vuejs/vue-devtools'
        );
      }
    }
    if ("development" !== 'production' &&
      "development" !== 'test' &&
      config.productionTip !== false &&
      typeof console !== 'undefined'
    ) {
      console[console.info ? 'info' : 'log'](
        "You are running Vue in development mode.\n" +
        "Make sure to turn on production mode when deploying for production.\n" +
        "See more tips at https://vuejs.org/guide/deployment.html"
      );
    }
  }, 0);
}

/*  */

var defaultTagRE = /\{\{((?:.|\n)+?)\}\}/g;
var regexEscapeRE = /[-.*+?^${}()|[\]\/\\]/g;

var buildRegex = cached(function (delimiters) {
  var open = delimiters[0].replace(regexEscapeRE, '\\$&');
  var close = delimiters[1].replace(regexEscapeRE, '\\$&');
  return new RegExp(open + '((?:.|\\n)+?)' + close, 'g')
});


// 解析文字节点
function parseText (
  text,
  delimiters
) {
  var tagRE = delimiters ? buildRegex(delimiters) : defaultTagRE;
  if (!tagRE.test(text)) {
    return
  }
  var tokens = [];
  var rawTokens = [];
  var lastIndex = tagRE.lastIndex = 0;
  var match, index, tokenValue;
  while ((match = tagRE.exec(text))) {
    index = match.index;
    // push text token
    if (index > lastIndex) {
      rawTokens.push(tokenValue = text.slice(lastIndex, index));
      tokens.push(JSON.stringify(tokenValue));
    }
    // tag token
    var exp = parseFilters(match[1].trim());
    tokens.push(("_s(" + exp + ")"));
    rawTokens.push({ '@binding': exp });
    lastIndex = index + match[0].length;
  }
  if (lastIndex < text.length) {
    rawTokens.push(tokenValue = text.slice(lastIndex));
    tokens.push(JSON.stringify(tokenValue));
  }
  return {
    expression: tokens.join('+'),
    tokens: rawTokens
  }
}

/*  */
// 动画类的绑定元素上
function transformNode (el, options) {
  var warn = options.warn || baseWarn;
  var staticClass = getAndRemoveAttr(el, 'class');
  if ("development" !== 'production' && staticClass) {
    var res = parseText(staticClass, options.delimiters);
    if (res) {
      warn(
        "class=\"" + staticClass + "\": " +
        'Interpolation inside attributes has been removed. ' +
        'Use v-bind or the colon shorthand instead. For example, ' +
        'instead of <div class="{{ val }}">, use <div :class="val">.'
      );
    }
  }
  if (staticClass) {
    el.staticClass = JSON.stringify(staticClass);
  }
  var classBinding = getBindingAttr(el, 'class', false /* getStatic */);
  if (classBinding) {
    el.classBinding = classBinding;
  }
}
// 类的集合
function genData (el) {
  var data = '';
  if (el.staticClass) {
    data += "staticClass:" + (el.staticClass) + ",";
  }
  if (el.classBinding) {
    data += "class:" + (el.classBinding) + ",";
  }
  return data
}

var klass$1 = {
  staticKeys: ['staticClass'],
  transformNode: transformNode,
  genData: genData
}

/*  */
// 行内样式
function transformNode$1 (el, options) {
  var warn = options.warn || baseWarn;
  var staticStyle = getAndRemoveAttr(el, 'style');
  if (staticStyle) {
    /* istanbul ignore if */
    {
      var res = parseText(staticStyle, options.delimiters);
      if (res) {
        warn(
          "style=\"" + staticStyle + "\": " +
          'Interpolation inside attributes has been removed. ' +
          'Use v-bind or the colon shorthand instead. For example, ' +
          'instead of <div style="{{ val }}">, use <div :style="val">.'
        );
      }
    }
    el.staticStyle = JSON.stringify(parseStyleText(staticStyle));
  }

  var styleBinding = getBindingAttr(el, 'style', false /* getStatic */);
  if (styleBinding) {
    el.styleBinding = styleBinding;
  }
}
// style的行内样式
function genData$1 (el) {
  var data = '';
  if (el.staticStyle) {
    data += "staticStyle:" + (el.staticStyle) + ",";
  }
  if (el.styleBinding) {
    data += "style:(" + (el.styleBinding) + "),";
  }
  return data
}

var style$1 = {
  staticKeys: ['staticStyle'],
  transformNode: transformNode$1,
  genData: genData$1
}

/*  */

var decoder;

var he = {
  decode: function decode (html) {
    decoder = decoder || document.createElement('div');
    decoder.innerHTML = html;
    return decoder.textContent
  }
}

/*  */

var isUnaryTag = makeMap(
  'area,base,br,col,embed,frame,hr,img,input,isindex,keygen,' +
  'link,meta,param,source,track,wbr'
);

// Elements that you can, intentionally, leave open
// (and which close themselves)
var canBeLeftOpenTag = makeMap(
  'colgroup,dd,dt,li,options,p,td,tfoot,th,thead,tr,source'
);

// HTML5 tags https://html.spec.whatwg.org/multipage/indices.html#elements-3
// Phrasing Content https://html.spec.whatwg.org/multipage/dom.html#phrasing-content
var isNonPhrasingTag = makeMap(
  'address,article,aside,base,blockquote,body,caption,col,colgroup,dd,' +
  'details,dialog,div,dl,dt,fieldset,figcaption,figure,footer,form,' +
  'h1,h2,h3,h4,h5,h6,head,header,hgroup,hr,html,legend,li,menuitem,meta,' +
  'optgroup,option,param,rp,rt,source,style,summary,tbody,td,tfoot,th,thead,' +
  'title,tr,track'
);

/**
 * Not type-checking this file because it's mostly vendor code.
 */

/*!
 * HTML Parser By John Resig (ejohn.org)
 * Modified by Juriy "kangax" Zaytsev
 * Original code by Erik Arvidsson, Mozilla Public License
 * http://erik.eae.net/simplehtmlparser/simplehtmlparser.js
 */

// Regular Expressions for parsing tags and attributes
var attribute = /^\s*([^\s"'<>\/=]+)(?:\s*(=)\s*(?:"([^"]*)"+|'([^']*)'+|([^\s"'=<>`]+)))?/;
// could use https://www.w3.org/TR/1999/REC-xml-names-19990114/#NT-QName
// but for Vue templates we can enforce a simple charset
var ncname = '[a-zA-Z_][\\w\\-\\.]*';
var qnameCapture = "((?:" + ncname + "\\:)?" + ncname + ")";
var startTagOpen = new RegExp(("^<" + qnameCapture));
var startTagClose = /^\s*(\/?)>/;
var endTag = new RegExp(("^<\\/" + qnameCapture + "[^>]*>"));
var doctype = /^<!DOCTYPE [^>]+>/i;
// #7298: escape - to avoid being pased as HTML comment when inlined in page
var comment = /^<!\--/;
var conditionalComment = /^<!\[/;

var IS_REGEX_CAPTURING_BROKEN = false;
'x'.replace(/x(.)?/g, function (m, g) {
  IS_REGEX_CAPTURING_BROKEN = g === '';
});

// Special Elements (can contain anything)
var isPlainTextElement = makeMap('script,style,textarea', true);
var reCache = {};

var decodingMap = {
  '&lt;': '<',
  '&gt;': '>',
  '&quot;': '"',
  '&amp;': '&',
  '&#10;': '\n',
  '&#9;': '\t'
};
var encodedAttr = /&(?:lt|gt|quot|amp);/g;
var encodedAttrWithNewLines = /&(?:lt|gt|quot|amp|#10|#9);/g;

// #5992
var isIgnoreNewlineTag = makeMap('pre,textarea', true);
var shouldIgnoreFirstNewline = function (tag, html) { return tag && isIgnoreNewlineTag(tag) && html[0] === '\n'; };

function decodeAttr (value, shouldDecodeNewlines) {
  var re = shouldDecodeNewlines ? encodedAttrWithNewLines : encodedAttr;
  return value.replace(re, function (match) { return decodingMap[match]; })
}
// 解析html，最后返回的是文本的html文档，会在mounted周期执行
function parseHTML (html, options) {
  console.log(html,'last')
  var stack = [];
  var expectHTML = options.expectHTML;
  var isUnaryTag$$1 = options.isUnaryTag || no;
  var canBeLeftOpenTag$$1 = options.canBeLeftOpenTag || no;
  var index = 0;
  var last, lastTag;
  while (html) {
    last = html;
    // Make sure we're not in a plaintext content element like script/style
    //解析标签的类型 
    if (!lastTag || !isPlainTextElement(lastTag)) {
      var textEnd = html.indexOf('<');
      if (textEnd === 0) {
        // Comment:
        if (comment.test(html)) {
          var commentEnd = html.indexOf('-->');

          if (commentEnd >= 0) {
            if (options.shouldKeepComment) {
              options.comment(html.substring(4, commentEnd));
            }
            advance(commentEnd + 3);
            continue
          }
        }

        // http://en.wikipedia.org/wiki/Conditional_comment#Downlevel-revealed_conditional_comment
        if (conditionalComment.test(html)) {
          var conditionalEnd = html.indexOf(']>');

          if (conditionalEnd >= 0) {
            advance(conditionalEnd + 2);
            continue
          }
        }

        // Doctype:
        var doctypeMatch = html.match(doctype);
        if (doctypeMatch) {
          advance(doctypeMatch[0].length);
          continue
        }

        // End tag:
        var endTagMatch = html.match(endTag);
        if (endTagMatch) {
          var curIndex = index;
          advance(endTagMatch[0].length);
          parseEndTag(endTagMatch[1], curIndex, index);
          continue
        }

        // Start tag:
        var startTagMatch = parseStartTag();
        if (startTagMatch) {
          handleStartTag(startTagMatch);
          if (shouldIgnoreFirstNewline(lastTag, html)) {
            advance(1);
          }
          continue
        }
      }

      var text = (void 0), rest = (void 0), next = (void 0);
      if (textEnd >= 0) {
        rest = html.slice(textEnd);
        while (
          !endTag.test(rest) &&
          !startTagOpen.test(rest) &&
          !comment.test(rest) &&
          !conditionalComment.test(rest)
        ) {
          // < in plain text, be forgiving and treat it as text
          next = rest.indexOf('<', 1);
          if (next < 0) { break }
          textEnd += next;
          rest = html.slice(textEnd);
        }
        text = html.substring(0, textEnd);
        advance(textEnd);
      }

      if (textEnd < 0) {
        text = html;
        html = '';
      }

      if (options.chars && text) {
        options.chars(text);
      }
    } else {
      var endTagLength = 0;
      var stackedTag = lastTag.toLowerCase();
      var reStackedTag = reCache[stackedTag] || (reCache[stackedTag] = new RegExp('([\\s\\S]*?)(</' + stackedTag + '[^>]*>)', 'i'));
      var rest$1 = html.replace(reStackedTag, function (all, text, endTag) {
        endTagLength = endTag.length;
        if (!isPlainTextElement(stackedTag) && stackedTag !== 'noscript') {
          text = text
            .replace(/<!\--([\s\S]*?)-->/g, '$1') // #7298
            .replace(/<!\[CDATA\[([\s\S]*?)]]>/g, '$1');
        }
        if (shouldIgnoreFirstNewline(stackedTag, text)) {
          text = text.slice(1);
        }
        if (options.chars) {
          options.chars(text);
        }
        return ''
      });
      index += html.length - rest$1.length;
      html = rest$1;
      parseEndTag(stackedTag, index - endTagLength, index);
    }

    if (html === last) {
      options.chars && options.chars(html);
      if ("development" !== 'production' && !stack.length && options.warn) {
        options.warn(("Mal-formatted tag at end of template: \"" + html + "\""));
      }
      break
    }
  }

  // Clean up any remaining tags
  parseEndTag();

  function advance (n) {
    index += n;
    html = html.substring(n);
  }
  
  function parseStartTag () {
    var start = html.match(startTagOpen);
    if (start) {
      var match = {
        tagName: start[1],
        attrs: [],
        start: index
      };
      advance(start[0].length);
      var end, attr;
      while (!(end = html.match(startTagClose)) && (attr = html.match(attribute))) {
        advance(attr[0].length);
        match.attrs.push(attr);
      }
      if (end) {
        match.unarySlash = end[1];
        advance(end[0].length);
        match.end = index;
        return match
      }
    }
  }
  // 解析起始标签
  function handleStartTag (match) {
    var tagName = match.tagName;
    var unarySlash = match.unarySlash;

    if (expectHTML) {
      if (lastTag === 'p' && isNonPhrasingTag(tagName)) {
        parseEndTag(lastTag);
      }
      if (canBeLeftOpenTag$$1(tagName) && lastTag === tagName) {
        parseEndTag(tagName);
      }
    }

    var unary = isUnaryTag$$1(tagName) || !!unarySlash;

    var l = match.attrs.length;
    var attrs = new Array(l);
    for (var i = 0; i < l; i++) {
      var args = match.attrs[i];
      // hackish work around FF bug https://bugzilla.mozilla.org/show_bug.cgi?id=369778
      if (IS_REGEX_CAPTURING_BROKEN && args[0].indexOf('""') === -1) {
        if (args[3] === '') { delete args[3]; }
        if (args[4] === '') { delete args[4]; }
        if (args[5] === '') { delete args[5]; }
      }
      var value = args[3] || args[4] || args[5] || '';
      var shouldDecodeNewlines = tagName === 'a' && args[1] === 'href'
        ? options.shouldDecodeNewlinesForHref
        : options.shouldDecodeNewlines;
      attrs[i] = {
        name: args[1],
        value: decodeAttr(value, shouldDecodeNewlines)
      };
    }

    if (!unary) {
      stack.push({ tag: tagName, lowerCasedTag: tagName.toLowerCase(), attrs: attrs });
      lastTag = tagName;
    }

    if (options.start) {
      options.start(tagName, attrs, unary, match.start, match.end);
    }
  }
  // 解析结束标签
  function parseEndTag (tagName, start, end) {
    var pos, lowerCasedTagName;
    if (start == null) { start = index; }
    if (end == null) { end = index; }

    if (tagName) {
      lowerCasedTagName = tagName.toLowerCase();
    }

    // Find the closest opened tag of the same type
    if (tagName) {
      for (pos = stack.length - 1; pos >= 0; pos--) {
        if (stack[pos].lowerCasedTag === lowerCasedTagName) {
          break
        }
      }
    } else {
      // If no tag name is provided, clean shop
      pos = 0;
    }

    if (pos >= 0) {
      // Close all the open elements, up the stack
      for (var i = stack.length - 1; i >= pos; i--) {
        if ("development" !== 'production' &&
          (i > pos || !tagName) &&
          options.warn
        ) {
          options.warn(
            ("tag <" + (stack[i].tag) + "> has no matching end tag.")
          );
        }
        if (options.end) {
          options.end(stack[i].tag, start, end);
        }
      }

      // Remove the open elements from the stack
      stack.length = pos;
      lastTag = pos && stack[pos - 1].tag;
    } else if (lowerCasedTagName === 'br') {
      if (options.start) {
        options.start(tagName, [], true, start, end);
      }
    } else if (lowerCasedTagName === 'p') {
      if (options.start) {
        options.start(tagName, [], false, start, end);
      }
      if (options.end) {
        options.end(tagName, start, end);
      }
    }
  }
  console.log(html,'html')
}

/*  */

var onRE = /^@|^v-on:/;
var dirRE = /^v-|^@|^:/;
var forAliasRE = /([^]*?)\s+(?:in|of)\s+([^]*)/;
var forIteratorRE = /,([^,\}\]]*)(?:,([^,\}\]]*))?$/;
var stripParensRE = /^\(|\)$/g;

var argRE = /:(.*)$/;
var bindRE = /^:|^v-bind:/;
var modifierRE = /\.[^.]+/g;

var decodeHTMLCached = cached(he.decode);

// configurable state
var warn$2;
var delimiters;
var transforms;
var preTransforms;
var postTransforms;
var platformIsPreTag;
var platformMustUseProp;
var platformGetTagNamespace;


// 创建ast 虚拟语法树
function createASTElement (
  tag,
  attrs,
  parent
) {
  return {
    type: 1,
    tag: tag,
    attrsList: attrs,
    attrsMap: makeAttrsMap(attrs),
    parent: parent,
    children: []
  }
}

/**
 * Convert HTML string to AST.
 */
function parse (
  template,
  options
) {
  warn$2 = options.warn || baseWarn;

  platformIsPreTag = options.isPreTag || no;
  platformMustUseProp = options.mustUseProp || no;
  platformGetTagNamespace = options.getTagNamespace || no;

  transforms = pluckModuleFunction(options.modules, 'transformNode');
  preTransforms = pluckModuleFunction(options.modules, 'preTransformNode');
  postTransforms = pluckModuleFunction(options.modules, 'postTransformNode');

  delimiters = options.delimiters;

  var stack = [];
  var preserveWhitespace = options.preserveWhitespace !== false;
  var root;
  var currentParent;
  var inVPre = false;
  var inPre = false;
  var warned = false;

  function warnOnce (msg) {
    if (!warned) {
      warned = true;
      warn$2(msg);
    }
  }

  function closeElement (element) {
    // check pre state
    if (element.pre) {
      inVPre = false;
    }
    if (platformIsPreTag(element.tag)) {
      inPre = false;
    }
    // apply post-transforms
    for (var i = 0; i < postTransforms.length; i++) {
      postTransforms[i](element, options);
    }
  }

  parseHTML(template, {
    warn: warn$2,
    expectHTML: options.expectHTML,
    isUnaryTag: options.isUnaryTag,
    canBeLeftOpenTag: options.canBeLeftOpenTag,
    shouldDecodeNewlines: options.shouldDecodeNewlines,
    shouldDecodeNewlinesForHref: options.shouldDecodeNewlinesForHref,
    shouldKeepComment: options.comments,
    start: function start (tag, attrs, unary) {
      // check namespace.
      // inherit parent ns if there is one
      var ns = (currentParent && currentParent.ns) || platformGetTagNamespace(tag);

      // handle IE svg bug
      /* istanbul ignore if */
      if (isIE && ns === 'svg') {
        attrs = guardIESVGBug(attrs);
      }

      var element = createASTElement(tag, attrs, currentParent);
      if (ns) {
        element.ns = ns;
      }

      if (isForbiddenTag(element) && !isServerRendering()) {
        element.forbidden = true;
        "development" !== 'production' && warn$2(
          'Templates should only be responsible for mapping the state to the ' +
          'UI. Avoid placing tags with side-effects in your templates, such as ' +
          "<" + tag + ">" + ', as they will not be parsed.'
        );
      }

      // apply pre-transforms
      for (var i = 0; i < preTransforms.length; i++) {
        element = preTransforms[i](element, options) || element;
      }

      if (!inVPre) {
        processPre(element);
        if (element.pre) {
          inVPre = true;
        }
      }
      if (platformIsPreTag(element.tag)) {
        inPre = true;
      }
      if (inVPre) {
        processRawAttrs(element);
      } else if (!element.processed) {
        // structural directives
        processFor(element);
        processIf(element);
        processOnce(element);
        // element-scope stuff
        processElement(element, options);
      }

      function checkRootConstraints (el) {
        {
          if (el.tag === 'slot' || el.tag === 'template') {
            warnOnce(
              "Cannot use <" + (el.tag) + "> as component root element because it may " +
              'contain multiple nodes.'
            );
          }
          if (el.attrsMap.hasOwnProperty('v-for')) {
            warnOnce(
              'Cannot use v-for on stateful component root element because ' +
              'it renders multiple elements.'
            );
          }
        }
      }

      // tree management
      if (!root) {
        root = element;
        checkRootConstraints(root);
      } else if (!stack.length) {
        // allow root elements with v-if, v-else-if and v-else
        if (root.if && (element.elseif || element.else)) {
          checkRootConstraints(element);
          addIfCondition(root, {
            exp: element.elseif,
            block: element
          });
        } else {
          warnOnce(
            "Component template should contain exactly one root element. " +
            "If you are using v-if on multiple elements, " +
            "use v-else-if to chain them instead."
          );
        }
      }
      if (currentParent && !element.forbidden) {
        if (element.elseif || element.else) {
          processIfConditions(element, currentParent);
        } else if (element.slotScope) { // scoped slot
          currentParent.plain = false;
          var name = element.slotTarget || '"default"';(currentParent.scopedSlots || (currentParent.scopedSlots = {}))[name] = element;
        } else {
          currentParent.children.push(element);
          element.parent = currentParent;
        }
      }
      if (!unary) {
        currentParent = element;
        stack.push(element);
      } else {
        closeElement(element);
      }
    },

    end: function end () {
      // remove trailing whitespace
      var element = stack[stack.length - 1];
      var lastNode = element.children[element.children.length - 1];
      if (lastNode && lastNode.type === 3 && lastNode.text === ' ' && !inPre) {
        element.children.pop();
      }
      // pop stack
      stack.length -= 1;
      currentParent = stack[stack.length - 1];
      closeElement(element);
    },

    chars: function chars (text) {
      if (!currentParent) {
        {
          if (text === template) {
            warnOnce(
              'Component template requires a root element, rather than just text.'
            );
          } else if ((text = text.trim())) {
            warnOnce(
              ("text \"" + text + "\" outside root element will be ignored.")
            );
          }
        }
        return
      }
      // IE textarea placeholder bug
      /* istanbul ignore if */
      if (isIE &&
        currentParent.tag === 'textarea' &&
        currentParent.attrsMap.placeholder === text
      ) {
        return
      }
      var children = currentParent.children;
      text = inPre || text.trim()
        ? isTextTag(currentParent) ? text : decodeHTMLCached(text)
        // only preserve whitespace if its not right after a starting tag
        : preserveWhitespace && children.length ? ' ' : '';
      if (text) {
        var res;
        if (!inVPre && text !== ' ' && (res = parseText(text, delimiters))) {
          children.push({
            type: 2,
            expression: res.expression,
            tokens: res.tokens,
            text: text
          });
        } else if (text !== ' ' || !children.length || children[children.length - 1].text !== ' ') {
          children.push({
            type: 3,
            text: text
          });
        }
      }
    },
    comment: function comment (text) {
      currentParent.children.push({
        type: 3,
        text: text,
        isComment: true
      });
    }
  });
  return root
}
// 是否有atrrMap中有v-pre参数，将el.pre属性设置为true,跳过标签
function processPre (el) {
  if (getAndRemoveAttr(el, 'v-pre') != null) {
    el.pre = true;
  }
}
// 将el.attrsList中的json字符串解析为el.attr数组
function processRawAttrs (el) {
  var l = el.attrsList.length;
  if (l) {
    var attrs = el.attrs = new Array(l);
    for (var i = 0; i < l; i++) {
      attrs[i] = {
        name: el.attrsList[i].name,
        value: JSON.stringify(el.attrsList[i].value)
      };
    }
  } else if (!el.pre) {
    // non root node in pre blocks with no attributes
    el.plain = true;
  }
}
// 解析 ast树
function processElement (element, options) {
  processKey(element);

  // determine whether this is a plain element after
  // removing structural attributes
  element.plain = !element.key && !element.attrsList.length;

  processRef(element);
  processSlot(element);
  processComponent(element);
  for (var i = 0; i < transforms.length; i++) {
    element = transforms[i](element, options) || element;
  }
  processAttrs(element);
}
// 解析ke.key
function processKey (el) {
  var exp = getBindingAttr(el, 'key');
  if (exp) {
    if ("development" !== 'production' && el.tag === 'template') {
      warn$2("<template> cannot be keyed. Place the key on real elements instead.");
    }
    el.key = exp;
  }
}
// 处理el中ref属性
function processRef (el) {
  var ref = getBindingAttr(el, 'ref');
  if (ref) {
    el.ref = ref;
    el.refInFor = checkInFor(el);
  }
}
// 处理el中v-for
function processFor (el) {
  var exp;
  if ((exp = getAndRemoveAttr(el, 'v-for'))) {
    var res = parseFor(exp);
    if (res) {
      extend(el, res);
    } else {
      warn$2(
        ("Invalid v-for expression: " + exp)
      );
    }
  }
}


// 解析v-for
function parseFor (exp) {
  var inMatch = exp.match(forAliasRE);
  if (!inMatch) { return }
  var res = {};
  res.for = inMatch[2].trim();
  var alias = inMatch[1].trim().replace(stripParensRE, '');
  var iteratorMatch = alias.match(forIteratorRE);
  if (iteratorMatch) {
    res.alias = alias.replace(forIteratorRE, '');
    res.iterator1 = iteratorMatch[1].trim();
    if (iteratorMatch[2]) {
      res.iterator2 = iteratorMatch[2].trim();
    }
  } else {
    res.alias = alias;
  }
  return res
}
//处理el中v-if v-else v-else-if
function processIf (el) {
  var exp = getAndRemoveAttr(el, 'v-if');
  if (exp) {
    el.if = exp;
    addIfCondition(el, {
      exp: exp,
      block: el
    });
  } else {
    if (getAndRemoveAttr(el, 'v-else') != null) {
      el.else = true;
    }
    var elseif = getAndRemoveAttr(el, 'v-else-if');
    if (elseif) {
      el.elseif = elseif;
    }
  }
}
// 处理if条件
function processIfConditions (el, parent) {
  var prev = findPrevElement(parent.children);
  if (prev && prev.if) {
    addIfCondition(prev, {
      exp: el.elseif,
      block: el
    });
  } else {
    warn$2(
      "v-" + (el.elseif ? ('else-if="' + el.elseif + '"') : 'else') + " " +
      "used on element <" + (el.tag) + "> without corresponding v-if."
    );
  }
}
// 找到v-pre中值
function findPrevElement (children) {
  var i = children.length;
  while (i--) {
    if (children[i].type === 1) {
      return children[i]
    } else {
      if ("development" !== 'production' && children[i].text !== ' ') {
        warn$2(
          "text \"" + (children[i].text.trim()) + "\" between v-if and v-else(-if) " +
          "will be ignored."
        );
      }
      children.pop();
    }
  }
}
// v-if的条件数组添加
function addIfCondition (el, condition) {
  if (!el.ifConditions) {
    el.ifConditions = [];
  }
  el.ifConditions.push(condition);
}
// 解析v-once
function processOnce (el) {
  var once$$1 = getAndRemoveAttr(el, 'v-once');
  if (once$$1 != null) {
    el.once = true;
  }
}
// 解析slot
function processSlot (el) {
  if (el.tag === 'slot') {
    el.slotName = getBindingAttr(el, 'name');
    if ("development" !== 'production' && el.key) {
      warn$2(
        "`key` does not work on <slot> because slots are abstract outlets " +
        "and can possibly expand into multiple elements. " +
        "Use the key on a wrapping element instead."
      );
    }
  } else {
    var slotScope;
    if (el.tag === 'template') {
      slotScope = getAndRemoveAttr(el, 'scope');
      /* istanbul ignore if */
      if ("development" !== 'production' && slotScope) {
        warn$2(
          "the \"scope\" attribute for scoped slots have been deprecated and " +
          "replaced by \"slot-scope\" since 2.5. The new \"slot-scope\" attribute " +
          "can also be used on plain elements in addition to <template> to " +
          "denote scoped slots.",
          true
        );
      }
      el.slotScope = slotScope || getAndRemoveAttr(el, 'slot-scope');
    } else if ((slotScope = getAndRemoveAttr(el, 'slot-scope'))) {
      /* istanbul ignore if */
      if ("development" !== 'production' && el.attrsMap['v-for']) {
        warn$2(
          "Ambiguous combined usage of slot-scope and v-for on <" + (el.tag) + "> " +
          "(v-for takes higher priority). Use a wrapper <template> for the " +
          "scoped slot to make it clearer.",
          true
        );
      }
      el.slotScope = slotScope;
    }
    var slotTarget = getBindingAttr(el, 'slot');
    if (slotTarget) {
      el.slotTarget = slotTarget === '""' ? '"default"' : slotTarget;
      // preserve slot as an attribute for native shadow DOM compat
      // only for non-scoped slots.
      if (el.tag !== 'template' && !el.slotScope) {
        addAttr(el, 'slot', slotTarget);
      }
    }
  }
}
// 处理is特性
function processComponent (el) {
  var binding;
  if ((binding = getBindingAttr(el, 'is'))) {
    el.component = binding;
  }
  if (getAndRemoveAttr(el, 'inline-template') != null) {
    el.inlineTemplate = true;
  }
}
// 处理attrs属性
function processAttrs (el) {
  var list = el.attrsList;
  var i, l, name, rawName, value, modifiers, isProp;
  for (i = 0, l = list.length; i < l; i++) {
    name = rawName = list[i].name;
    value = list[i].value;
    if (dirRE.test(name)) {
      // mark element as dynamic
      el.hasBindings = true;
      // modifiers
      modifiers = parseModifiers(name);
      if (modifiers) {
        name = name.replace(modifierRE, '');
      }
      if (bindRE.test(name)) { // v-bind
        name = name.replace(bindRE, '');
        value = parseFilters(value);
        isProp = false;
        if (modifiers) {
          if (modifiers.prop) {
            isProp = true;
            name = camelize(name);
            if (name === 'innerHtml') { name = 'innerHTML'; }
          }
          if (modifiers.camel) {
            name = camelize(name);
          }
          if (modifiers.sync) {
            addHandler(
              el,
              ("update:" + (camelize(name))),
              genAssignmentCode(value, "$event")
            );
          }
        }
        if (isProp || (
          !el.component && platformMustUseProp(el.tag, el.attrsMap.type, name)
        )) {
          addProp(el, name, value);
        } else {
          addAttr(el, name, value);
        }
      } else if (onRE.test(name)) { // v-on
        name = name.replace(onRE, '');
        addHandler(el, name, value, modifiers, false, warn$2);
      } else { // normal directives
        name = name.replace(dirRE, '');
        // parse arg
        var argMatch = name.match(argRE);
        var arg = argMatch && argMatch[1];
        if (arg) {
          name = name.slice(0, -(arg.length + 1));
        }
        addDirective(el, name, rawName, value, arg, modifiers);
        if ("development" !== 'production' && name === 'model') {
          checkForAliasModel(el, value);
        }
      }
    } else {
      // literal attribute
      {
        var res = parseText(value, delimiters);
        if (res) {
          warn$2(
            name + "=\"" + value + "\": " +
            'Interpolation inside attributes has been removed. ' +
            'Use v-bind or the colon shorthand instead. For example, ' +
            'instead of <div id="{{ val }}">, use <div :id="val">.'
          );
        }
      }
      addAttr(el, name, JSON.stringify(value));
      // #6887 firefox doesn't update muted state if set via attribute
      // even immediately after element creation
      if (!el.component &&
          name === 'muted' &&
          platformMustUseProp(el.tag, el.attrsMap.type, name)) {
        addProp(el, name, 'true');
      }
    }
  }
}
// 检查是否在v-for中
function checkInFor (el) {
  var parent = el;
  while (parent) {
    if (parent.for !== undefined) {
      return true
    }
    parent = parent.parent;
  }
  return false
}

function parseModifiers (name) {
  var match = name.match(modifierRE);
  if (match) {
    var ret = {};
    match.forEach(function (m) { ret[m.slice(1)] = true; });
    return ret
  }
}

function makeAttrsMap (attrs) {
  var map = {};
  for (var i = 0, l = attrs.length; i < l; i++) {
    if (
      "development" !== 'production' &&
      map[attrs[i].name] && !isIE && !isEdge
    ) {
      warn$2('duplicate attribute: ' + attrs[i].name);
    }
    map[attrs[i].name] = attrs[i].value;
  }
  return map
}

// for script (e.g. type="x/template") or style, do not decode content
// 是否是text标签，即script,style标签，不会解析
function isTextTag (el) {
  return el.tag === 'script' || el.tag === 'style'
}
// 是否是禁用标签
function isForbiddenTag (el) {
  return (
    el.tag === 'style' ||
    (el.tag === 'script' && (
      !el.attrsMap.type ||
      el.attrsMap.type === 'text/javascript'
    ))
  )
}

var ieNSBug = /^xmlns:NS\d+/;
var ieNSPrefix = /^NS\d+:/;

/* istanbul ignore next */
//修复ie svg的bug
function guardIESVGBug (attrs) {
  var res = [];
  for (var i = 0; i < attrs.length; i++) {
    var attr = attrs[i];
    if (!ieNSBug.test(attr.name)) {
      attr.name = attr.name.replace(ieNSPrefix, '');
      res.push(attr);
    }
  }
  return res
}
// 检查v-model在for循环中的绑定的检查
function checkForAliasModel (el, value) {
  var _el = el;
  while (_el) {
    if (_el.for && _el.alias === value) {
      warn$2(
        "<" + (el.tag) + " v-model=\"" + value + "\">: " +
        "You are binding v-model directly to a v-for iteration alias. " +
        "This will not be able to modify the v-for source array because " +
        "writing to the alias is like modifying a function local variable. " +
        "Consider using an array of objects and use v-model on an object property instead."
      );
    }
    _el = _el.parent;
  }
}

/*  */

/**
 * Expand input[v-model] with dyanmic type bindings into v-if-else chains
 * Turn this:
 *   <input v-model="data[type]" :type="type">
 * into this:
 * 首先会检查type是否是checkbox,如不是，检查是否是radio,如果不是，在用v-bind监听type,
 *   <input v-if="type === 'checkbox'" type="checkbox" v-model="data[type]">
 *   <input v-else-if="type === 'radio'" type="radio" v-model="data[type]">
 *   <input v-else :type="type" v-model="data[type]">
 */
// 处理input 
function preTransformNode (el, options) {
  if (el.tag === 'input') {
    var map = el.attrsMap;
    // 处理input,如果没有v-modle，不解析，直接返回
    if (!map['v-model']) {
      return
    }

    var typeBinding;
    if (map[':type'] || map['v-bind:type']) {
      typeBinding = getBindingAttr(el, 'type');
    }
    if (!map.type && !typeBinding && map['v-bind']) {
      typeBinding = "(" + (map['v-bind']) + ").type";
    }

    if (typeBinding) {
      var ifCondition = getAndRemoveAttr(el, 'v-if', true);
      var ifConditionExtra = ifCondition ? ("&&(" + ifCondition + ")") : "";
      var hasElse = getAndRemoveAttr(el, 'v-else', true) != null;
      var elseIfCondition = getAndRemoveAttr(el, 'v-else-if', true);
      // 1. checkbox
      // 克隆ast树
      var branch0 = cloneASTElement(el);
      // process for on the main node
      //检查v-for
      processFor(branch0);
      // 首先是检查 type是否是checkbox
      addRawAttr(branch0, 'type', 'checkbox');
      processElement(branch0, options);
      branch0.processed = true; // prevent it from double-processed
      branch0.if = "(" + typeBinding + ")==='checkbox'" + ifConditionExtra;
      addIfCondition(branch0, {
        exp: branch0.if,
        block: branch0
      });
      // 首先是检查 type是否是radio
      // 2. add radio else-if condition
      var branch1 = cloneASTElement(el);
      getAndRemoveAttr(branch1, 'v-for', true);
      addRawAttr(branch1, 'type', 'radio');
      processElement(branch1, options);
      addIfCondition(branch0, {
        exp: "(" + typeBinding + ")==='radio'" + ifConditionExtra,
        block: branch1
      });
      // 最后用v-bind绑定type
      // 3. other
      var branch2 = cloneASTElement(el);
      getAndRemoveAttr(branch2, 'v-for', true);
      addRawAttr(branch2, ':type', typeBinding);
      processElement(branch2, options);
      addIfCondition(branch0, {
        exp: ifCondition,
        block: branch2
      });

      if (hasElse) {
        branch0.else = true;
      } else if (elseIfCondition) {
        branch0.elseif = elseIfCondition;
      }

      return branch0
    }
  }
}
// 克隆ast树
function cloneASTElement (el) {
  return createASTElement(el.tag, el.attrsList.slice(), el.parent)
}

var model$2 = {
  preTransformNode: preTransformNode
}

var modules$1 = [
  klass$1,
  style$1,
  model$2
]

/*  */

function text (el, dir) {
  if (dir.value) {
    addProp(el, 'textContent', ("_s(" + (dir.value) + ")"));
  }
}