大概1600-2600行
/**
* Get the default value of a prop.
*/
// 得到prop的初始值
function getPropDefaultValue (vm, prop, key) {
// no default, return undefined
if (!hasOwn(prop, 'default')) {
return undefined
}
var def = prop.default;
// warn against non-factory defaults for Object & Array
if ("development" !== 'production' && isObject(def)) {
warn(
'Invalid default value for prop "' + key + '": ' +
'Props with type Object/Array must use a factory function ' +
'to return the default value.',
vm
);
}
// the raw prop value was also undefined from previous render,
// return previous default value to avoid unnecessary watcher trigger
if (vm && vm.$options.propsData &&
vm.$options.propsData[key] === undefined &&
vm._props[key] !== undefined
) {
return vm._props[key]
}
// call factory function for non-Function types
// a value is Function if its prototype is function even across different execution context
return typeof def === 'function' && getType(prop.type) !== 'Function'
? def.call(vm)
: def
}
/**
* Assert hether a prop is valid.
*/
function assertProp (
prop,
name,
value,
vm,
absent
) {
if (prop.required && absent) {
warn(
'Missing required prop: "' + name + '"',
vm
);
return
}
if (value == null && !prop.required) {
return
}
var type = prop.type;
var valid = !type || type === true;
var expectedTypes = [];
if (type) {
if (!Array.isArray(type)) {
type = [type];
}
for (var i = 0; i < type.length && !valid; i++) {
var assertedType = assertType(value, type[i]);
expectedTypes.push(assertedType.expectedType || '');
valid = assertedType.valid;
}
}
if (!valid) {
warn(
"Invalid prop: type check failed for prop \"" + name + "\"." +
" Expected " + (expectedTypes.map(capitalize).join(', ')) +
", got " + (toRawType(value)) + ".",
vm
);
return
}
var validator = prop.validator;
if (validator) {
if (!validator(value)) {
warn(
'Invalid prop: custom validator check failed for prop "' + name + '".',
vm
);
}
}
}
var simpleCheckRE = /^(String|Number|Boolean|Function|Symbol)$/;
function assertType (value, type) {
var valid;
var expectedType = getType(type);
if (simpleCheckRE.test(expectedType)) {
var t = typeof value;
valid = t === expectedType.toLowerCase();
// for primitive wrapper objects
if (!valid && t === 'object') {
valid = value instanceof type;
}
} else if (expectedType === 'Object') {
valid = isPlainObject(value);
} else if (expectedType === 'Array') {
valid = Array.isArray(value);
} else {
valid = value instanceof type;
}
return {
valid: valid,
expectedType: expectedType
}
}
/**
* Use function string name to check built-in types,
* because a simple equality check will fail when running
* across different vms / iframes.
*/
// 获取函数表达式
function getType (fn) {
var match = fn && fn.toString().match(/^\s*function (\w+)/);
return match ? match[1] : ''
}
function isSameType (a, b) {
return getType(a) === getType(b)
}
function getTypeIndex (type, expectedTypes) {
if (!Array.isArray(expectedTypes)) {
return isSameType(expectedTypes, type) ? 0 : -1
}
for (var i = 0, len = expectedTypes.length; i < len; i++) {
if (isSameType(expectedTypes[i], type)) {
return i
}
}
return -1
}
/* */
// 错误处理
function handleError (err, vm, info) {
if (vm) {
var cur = vm;
while ((cur = cur.$parent)) {
var hooks = cur.$options.errorCaptured;
if (hooks) {
for (var i = 0; i < hooks.length; i++) {
try {
var capture = hooks[i].call(cur, err, vm, info) === false;
if (capture) { return }
} catch (e) {
globalHandleError(e, cur, 'errorCaptured hook');
}
}
}
}
}
globalHandleError(err, vm, info);
}
function globalHandleError (err, vm, info) {
if (config.errorHandler) {
try {
return config.errorHandler.call(null, err, vm, info)
} catch (e) {
logError(e, null, 'config.errorHandler');
}
}
logError(err, vm, info);
}
function logError (err, vm, info) {
{
warn(("Error in " + info + ": \"" + (err.toString()) + "\""), vm);
}
/* istanbul ignore else */
if ((inBrowser || inWeex) && typeof console !== 'undefined') {
console.error(err);
} else {
throw err
}
}
/* */
/* globals MessageChannel */
var callbacks = [];
var pending = false;
// 回调数组执行
function flushCallbacks () {
pending = false;
var copies = callbacks.slice(0);
callbacks.length = 0;
for (var i = 0; i < copies.length; i++) {
copies[i]();
}
}
// Here we have async deferring wrappers using both microtasks and (macro) tasks.
// In < 2.4 we used microtasks everywhere, but there are some scenarios where
// microtasks have too high a priority and fire in between supposedly
// sequential events (e.g. #4521, #6690) or even between bubbling of the same
// event (#6566). However, using (macro) tasks everywhere also has subtle problems
// when state is changed right before repaint (e.g. #6813, out-in transitions).
// Here we use microtask by default, but expose a way to force (macro) task when
// needed (e.g. in event handlers attached by v-on).
var microTimerFunc;
var macroTimerFunc;
var useMacroTask = false;
// Determine (macro) task defer implementation.
// Technically setImmediate should be the ideal choice, but it's only available
// in IE. The only polyfill that consistently queues the callback after all DOM
// events triggered in the same loop is by using MessageChannel.
/* istanbul ignore if */
// 异步执行 如果支持setImmediate
if (typeof setImmediate !== 'undefined' && isNative(setImmediate)) {
macroTimerFunc = function () {
setImmediate(flushCallbacks);
};
//如果支持MessageChannel
} else if (typeof MessageChannel !== 'undefined' && (
isNative(MessageChannel) ||
// PhantomJS
MessageChannel.toString() === '[object MessageChannelConstructor]'
)) {
var channel = new MessageChannel();
var port = channel.port2;
channel.port1.onmessage = flushCallbacks;
macroTimerFunc = function () {
port.postMessage(1);
};
} else {
// 最后执行setTimeout
/* istanbul ignore next */
macroTimerFunc = function () {
setTimeout(flushCallbacks, 0);
};
}
// Determine microtask defer implementation.
/* istanbul ignore next, $flow-disable-line */
// 如果支持promise,microTimerFunc变量赋予promise处理的结果
if (typeof Promise !== 'undefined' && isNative(Promise)) {
var p = Promise.resolve();
microTimerFunc = function () {
p.then(flushCallbacks);
// in problematic UIWebViews, Promise.then doesn't completely break, but
// it can get stuck in a weird state where callbacks are pushed into the
// microtask queue but the queue isn't being flushed, until the browser
// needs to do some other work, e.g. handle a timer. Therefore we can
// "force" the microtask queue to be flushed by adding an empty timer.
if (isIOS) { setTimeout(noop); }
};
} else {
// fallback to macro
microTimerFunc = macroTimerFunc;
}
/**
* Wrap a function so that if any code inside triggers state change,
* the changes are queued using a (macro) task instead of a microtask.
*/
function withMacroTask (fn) {
return fn._withTask || (fn._withTask = function () {
useMacroTask = true;
var res = fn.apply(null, arguments);
useMacroTask = false;
return res
})
}
// nextTick函数，使用macroTimerFunc或者microTimerFunc，取决设置的useMacroTask变量
function nextTick (cb, ctx) {
var _resolve;
callbacks.push(function () {
if (cb) {
try {
cb.call(ctx);
} catch (e) {
handleError(e, ctx, 'nextTick');
}
} else if (_resolve) {
_resolve(ctx);
}
});
if (!pending) {
pending = true;
if (useMacroTask) {
macroTimerFunc();
} else {
microTimerFunc();
}
}
// $flow-disable-line
if (!cb && typeof Promise !== 'undefined') {
return new Promise(function (resolve) {
_resolve = resolve;
})
}
}
/* */
var mark;
var measure;
// 使用performance进行性能监控
{
var perf = inBrowser && window.performance;
/* istanbul ignore if */
if (
perf &&
perf.mark &&
perf.measure &&
perf.clearMarks &&
perf.clearMeasures
) {
mark = function (tag) { return perf.mark(tag); };
measure = function (name, startTag, endTag) {
perf.measure(name, startTag, endTag);
perf.clearMarks(startTag);
perf.clearMarks(endTag);
perf.clearMeasures(name);
};
}
}
/* not type checking this file because flow doesn't play well with Proxy */
var initProxy;
// 定义一些特殊的字段不能作为组件或者属性和方法的回到提醒
{
var allowedGlobals = makeMap(
'Infinity,undefined,NaN,isFinite,isNaN,' +
'parseFloat,parseInt,decodeURI,decodeURIComponent,encodeURI,encodeURIComponent,' +
'Math,Number,Date,Array,Object,Boolean,String,RegExp,Map,Set,JSON,Intl,' +
'require' // for Webpack/Browserify
);
var warnNonPresent = function (target, key) {
warn(
"Property or method \"" + key + "\" is not defined on the instance but " +
'referenced during render. Make sure that this property is reactive, ' +
'either in the data option, or for class-based components, by ' +
'initializing the property. ' +
'See: https://vuejs.org/v2/guide/reactivity.html#Declaring-Reactive-Properties.',
target
);
};
// 是否支持proxy
var hasProxy =
typeof Proxy !== 'undefined' && isNative(Proxy);
if (hasProxy) {
// 一些键盘名不能自定义
var isBuiltInModifier = makeMap('stop,prevent,self,ctrl,shift,alt,meta,exact');
config.keyCodes = new Proxy(config.keyCodes, {
set: function set (target, key, value) {
if (isBuiltInModifier(key)) {
warn(("Avoid overwriting built-in modifier in config.keyCodes: ." + key));
return false
} else {
target[key] = value;
return true
}
}
});
}
// key是否在target属性中，或者不是全局的参数或者字母开头是‘-’
var hasHandler = {
has: function has (target, key) {
var has = key in target;
var isAllowed = allowedGlobals(key) || key.charAt(0) === '_';
if (!has && !isAllowed) {
warnNonPresent(target, key);
}
return has || !isAllowed
}
};
// 返回target[key]属性值
var getHandler = {
get: function get (target, key) {
if (typeof key === 'string' && !(key in target)) {
warnNonPresent(target, key);
}
return target[key]
}
};
//proxy函数的处理
initProxy = function initProxy (vm) {
if (hasProxy) {
// determine which proxy handler to use
var options = vm.$options;
var handlers = options.render && options.render._withStripped
? getHandler
: hasHandler;
vm._renderProxy = new Proxy(vm, handlers);
} else {
vm._renderProxy = vm;
}
};
}
/* */
// 设置新的set
var seenObjects = new _Set();
/**
* Recursively traverse an object to evoke all converted
* getters, so that every nested property inside the object
* is collected as a "deep" dependency.
*/
// 触发一个对象或者数组的每个属性的getter，
function traverse (val) {
_traverse(val, seenObjects);
seenObjects.clear();
}
// 遍历数组或者对象下的每个元素或者属性并且递归，确保每个下面的属性都是可以监听
function _traverse (val, seen) {
var i, keys;
var isA = Array.isArray(val);
if ((!isA && !isObject(val)) || Object.isFrozen(val) || val instanceof VNode) {
return
}
if (val.__ob__) {
var depId = val.__ob__.dep.id;
if (seen.has(depId)) {
return
}
seen.add(depId);
}
if (isA) {
i = val.length;
while (i--) { _traverse(val[i], seen); }
} else {
keys = Object.keys(val);
i = keys.length;
while (i--) { _traverse(val[keys[i]], seen); }
}
}
/* */
// 事件event名，以&，~，！开头的名字作为对象合集返回
var normalizeEvent = cached(function (name) {
var passive = name.charAt(0) === '&';
name = passive ? name.slice(1) : name;
var once$$1 = name.charAt(0) === '~'; // Prefixed last, checked first
name = once$$1 ? name.slice(1) : name;
var capture = name.charAt(0) === '!';
name = capture ? name.slice(1) : name;
return {
name: name,
once: once$$1,
capture: capture,
passive: passive
}
});
// 将传参a传递给一个申明的函数，并且这个函数的传参b，会被传参a作为参数调用
function createFnInvoker (fns) {
function invoker () {
var arguments$1 = arguments;
var fns = invoker.fns;
if (Array.isArray(fns)) {
var cloned = fns.slice();
for (var i = 0; i < cloned.length; i++) {
cloned[i].apply(null, arguments$1);
}
} else {
// return handler return value for single handlers
return fns.apply(null, arguments)
}
}
invoker.fns = fns;
return invoker
}
// 跟新监听器 v-on
function updateListeners (
on,
oldOn,
add,
remove$$1,
vm
) {
var name, def, cur, old, event;
// 遍历监听器
for (name in on) {
def = cur = on[name];
old = oldOn[name];
event = normalizeEvent(name);
/* istanbul ignore if */
// 如果当前监听事件没有函数，报错
if (isUndef(cur)) {
"development" !== 'production' && warn(
"Invalid handler for event \"" + (event.name) + "\": got " + String(cur),
vm
);
// 如果就的监听事件没有，新建新的事件
} else if (isUndef(old)) {
if (isUndef(cur.fns)) {
cur = on[name] = createFnInvoker(cur);
}
//添加监听事件名，函数，以及事件的条件
add(event.name, cur, event.once, event.capture, event.passive, event.params);
// 如果当前不等于以前的，函数改为现在的，事件改为之前的
} else if (cur !== old) {
old.fns = cur;
on[name] = old;
}
}
//在旧事件中有而新事件中没有的删除
for (name in oldOn) {
if (isUndef(on[name])) {
event = normalizeEvent(name);
remove$$1(event.name, oldOn[name], event.capture);
}
}
}
/* */
// 合并Vnode的生命周期
function mergeVNodeHook (def, hookKey, hook) {
if (def instanceof VNode) {
def = def.data.hook || (def.data.hook = {});
}
var invoker;
var oldHook = def[hookKey];
// hook被调用后将其函数和hook删除，使其只能被调用一次
function wrappedHook () {
hook.apply(this, arguments);
// important: remove merged hook to ensure it's called only once
// and prevent memory leak
remove(invoker.fns, wrappedHook);
}
if (isUndef(oldHook)) {
// no existing hook
invoker = createFnInvoker([wrappedHook]);
} else {
/* istanbul ignore if */
if (isDef(oldHook.fns) && isTrue(oldHook.merged)) {
// already a merged invoker
invoker = oldHook;
invoker.fns.push(wrappedHook);
} else {
// existing plain hook
invoker = createFnInvoker([oldHook, wrappedHook]);
}
}
invoker.merged = true;
def[hookKey] = invoker;
}
/* */
// 获取Vnode中的props和attr
function extractPropsFromVNodeData (
data,
Ctor,
tag
) {
// we are only extracting raw values here.
// validation and default values are handled in the child
// component itself.
var propOptions = Ctor.options.props;
if (isUndef(propOptions)) {
return
}
var res = {};
var attrs = data.attrs;
var props = data.props;
if (isDef(attrs) || isDef(props)) {
for (var key in propOptions) {
var altKey = hyphenate(key);
{
var keyInLowerCase = key.toLowerCase();
if (
key !== keyInLowerCase &&
attrs && hasOwn(attrs, keyInLowerCase)
) {
tip(
"Prop \"" + keyInLowerCase + "\" is passed to component " +
(formatComponentName(tag || Ctor)) + ", but the declared prop name is" +
" \"" + key + "\". " +
"Note that HTML attributes are case-insensitive and camelCased " +
"props need to use their kebab-case equivalents when using in-DOM " +
"templates. You should probably use \"" + altKey + "\" instead of \"" + key + "\"."
);
}
}
checkProp(res, props, key, altKey, true) ||
checkProp(res, attrs, key, altKey, false);
}
}
return res
}
// 检查是否含有prop,或者attr
function checkProp (
res,
hash,
key,
altKey,
preserve
) {
if (isDef(hash)) {
if (hasOwn(hash, key)) {
res[key] = hash[key];
if (!preserve) {
delete hash[key];
}
return true
} else if (hasOwn(hash, altKey)) {
res[key] = hash[altKey];
if (!preserve) {
delete hash[altKey];
}
return true
}
}
return false
}
/* */
// The template compiler attempts to minimize the need for normalization by
// statically analyzing the template at compile time.
//
// For plain HTML markup, normalization can be completely skipped because the
// generated render function is guaranteed to return Array<VNode>. There are
// two cases where extra normalization is needed:
// 1. When the children contains components - because a functional component
// may return an Array instead of a single root. In this case, just a simple
// normalization is needed - if any child is an Array, we flatten the whole
// thing with Array.prototype.concat. It is guaranteed to be only 1-level deep
// because functional components already normalize their own children.
//
// 如果children数组中含有数组，将数组与children合并
function simpleNormalizeChildren (children) {
for (var i = 0; i < children.length; i++) {
if (Array.isArray(children[i])) {
return Array.prototype.concat.apply([], children)
}
}
return children
}
// 2. When the children contains constructs that always generated nested Arrays,
// e.g. <template>, <slot>, v-for, or when the children is provided by user
// with hand-written render functions / JSX. In such cases a full normalization
// is needed to cater to all possible types of children values.
function normalizeChildren (children) {
return isPrimitive(children)
? [createTextVNode(children)]
: Array.isArray(children)
? normalizeArrayChildren(children)
: undefined
}
// 是否是文字vnode
function isTextNode (node) {
return isDef(node) && isDef(node.text) && isFalse(node.isComment)
}
// 判断children中的子元素是不是数组，如果是数组低估调用，作为数组返回
function normalizeArrayChildren (children, nestedIndex) {
var res = [];
var i, c, lastIndex, last;
for (i = 0; i < children.length; i++) {
c = children[i];
if (isUndef(c) || typeof c === 'boolean') { continue }
lastIndex = res.length - 1;
last = res[lastIndex];
// nested
if (Array.isArray(c)) {
if (c.length > 0) {
c = normalizeArrayChildren(c, ((nestedIndex || '') + "_" + i));
// merge adjacent text nodes
if (isTextNode(c[0]) && isTextNode(last)) {
res[lastIndex] = createTextVNode(last.text + (c[0]).text);
c.shift();
}
res.push.apply(res, c);
}
} else if (isPrimitive(c)) {
if (isTextNode(last)) {
// merge adjacent text nodes
// this is necessary for SSR hydration because text nodes are
// essentially merged when rendered to HTML strings
res[lastIndex] = createTextVNode(last.text + c);
} else if (c !== '') {
// convert primitive to vnode
res.push(createTextVNode(c));
}
} else {
if (isTextNode(c) && isTextNode(last)) {
// merge adjacent text nodes
res[lastIndex] = createTextVNode(last.text + c.text);
} else {
// default key for nested array children (likely generated by v-for)
if (isTrue(children._isVList) &&
isDef(c.tag) &&
isUndef(c.key) &&
isDef(nestedIndex)) {
c.key = "__vlist" + nestedIndex + "_" + i + "__";
}
res.push(c);
}
}
}
return res
}
/* */
function ensureCtor (comp, base) {
if (
comp.__esModule ||
(hasSymbol && comp[Symbol.toStringTag] === 'Module')
) {
comp = comp.default;
}
return isObject(comp)
? base.extend(comp)
: comp
}
//创建异步组件
function createAsyncPlaceholder (
factory,
data,
context,
children,
tag
) {
var node = createEmptyVNode();
node.asyncFactory = factory;
node.asyncMeta = { data: data, context: context, children: children, tag: tag };
return node
}
// 执行异步组件，申明resolve,reject两个处理函数最后用promise
function resolveAsyncComponent (
factory,
baseCtor,
context
) {
if (isTrue(factory.error) && isDef(factory.errorComp)) {
return factory.errorComp
}
if (isDef(factory.resolved)) {
return factory.resolved
}
if (isTrue(factory.loading) && isDef(factory.loadingComp)) {
return factory.loadingComp
}
if (isDef(factory.contexts)) {
// already pending
factory.contexts.push(context);
} else {
var contexts = factory.contexts = [context];
var sync = true;
var forceRender = function () {
for (var i = 0, l = contexts.length; i < l; i++) {
contexts[i].$forceUpdate();
}
};
var resolve = once(function (res) {
// cache resolved
// 返回结果
factory.resolved = ensureCtor(res, baseCtor);
// invoke callbacks only if this is not a synchronous resolve
// (async resolves are shimmed as synchronous during SSR)
if (!sync) {
// 每个context强制
forceRender();
}
});
var reject = once(function (reason) {
"development" !== 'production' && warn(
"Failed to resolve async component: " + (String(factory)) +
(reason ? ("\nReason: " + reason) : '')
);
if (isDef(factory.errorComp)) {
factory.error = true;
forceRender();
}
});
var res = factory(resolve, reject);
if (isObject(res)) {
if (typeof res.then === 'function') {
// () => Promise
if (isUndef(factory.resolved)) {
res.then(resolve, reject);
}
} else if (isDef(res.component) && typeof res.component.then === 'function') {
res.component.then(resolve, reject);
if (isDef(res.error)) {
factory.errorComp = ensureCtor(res.error, baseCtor);
}
if (isDef(res.loading)) {
factory.loadingComp = ensureCtor(res.loading, baseCtor);
if (res.delay === 0) {
factory.loading = true;
} else {
setTimeout(function () {
if (isUndef(factory.resolved) && isUndef(factory.error)) {
factory.loading = true;
forceRender();
}
}, res.delay || 200);
}
}
if (isDef(res.timeout)) {
setTimeout(function () {
if (isUndef(factory.resolved)) {
reject(
"timeout (" + (res.timeout) + "ms)"
);
}
}, res.timeout);
}
}
}
sync = false;
// return in case resolved synchronously
return factory.loading
? factory.loadingComp
: factory.resolved
}
}
/* */
// 是否是异步组件
function isAsyncPlaceholder (node) {
return node.isComment && node.asyncFactory
}
/* */
// 获取第一个异步子组件
function getFirstComponentChild (children) {
if (Array.isArray(children)) {
for (var i = 0; i < children.length; i++) {
var c = children[i];
if (isDef(c) && (isDef(c.componentOptions) || isAsyncPlaceholder(c))) {
return c
}
}
}
}
/* */
/* */
// 初始化事件
function initEvents (vm) {
vm._events = Object.create(null);
vm._hasHookEvent = false;
// init parent attached events
var listeners = vm.$options._parentListeners;
if (listeners) {
updateComponentListeners(vm, listeners);
}
}
var target;
// 为事件添加函数，判断是否是once
function add (event, fn, once) {
if (once) {
target.$once(event, fn);
} else {
target.$on(event, fn);
}
}
// 实处事件绑定的函数
function remove$1 (event, fn) {
target.$off(event, fn);
}
// 跟新组件中的监听器
function updateComponentListeners (
vm,
listeners,
oldListeners
) {
target = vm;
updateListeners(listeners, oldListeners || {}, add, remove$1, vm);
target = undefined;
}
// vue原型链上绑定一些方法
function eventsMixin (Vue) {
var hookRE = /^hook:/;
// $on 将事件方法保存到vm下面的_events对应的数组下
Vue.prototype.$on = function (event, fn) {
var this$1 = this;
var vm = this;
if (Array.isArray(event)) {
for (var i = 0, l = event.length; i < l; i++) {
this$1.$on(event[i], fn);
}
} else {
(vm._events[event] || (vm._events[event] = [])).push(fn);
// optimize hook:event cost by using a boolean flag marked at registration
// instead of a hash lookup
if (hookRE.test(event)) {
vm._hasHookEvent = true;
}
}
return vm
};
// 单次执行函数
Vue.prototype.$once = function (event, fn) {
var vm = this;
function on () {
vm.$off(event, on);
fn.apply(vm, arguments);
}
on.fn = fn;
vm.$on(event, on);
return vm
};
// 将保存在_events下面的函数数组中特定的删除
Vue.prototype.$off = function (event, fn) {
var this$1 = this;
var vm = this;
// all
if (!arguments.length) {
vm._events = Object.create(null);
return vm
}
// array of events
if (Array.isArray(event)) {
for (var i = 0, l = event.length; i < l; i++) {
this$1.$off(event[i], fn);
}
return vm
}
// specific event
var cbs = vm._events[event];
if (!cbs) {
return vm
}
if (!fn) {
vm._events[event] = null;
return vm
}
if (fn) {
// specific handler
var cb;
var i$1 = cbs.length;
while (i$1--) {
cb = cbs[i$1];
if (cb === fn || cb.fn === fn) {
cbs.splice(i$1, 1);
break
}
}
}
return vm
};
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