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mithril.js
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;(function (global, factory) { // eslint-disable-line
"use strict"
/* eslint-disable no-undef */
var m = factory(global)
if (typeof module === "object" && module != null && module.exports) {
module.exports = m
} else if (typeof define === "function" && define.amd) {
define(function () { return m })
} else {
global.m = m
}
/* eslint-enable no-undef */
})(typeof window !== "undefined" ? window : this, function (global, undefined) { // eslint-disable-line
"use strict"
m.version = function () {
return "v0.2.5"
}
var hasOwn = {}.hasOwnProperty
var type = {}.toString
function isFunction(object) {
return typeof object === "function"
}
function isObject(object) {
return type.call(object) === "[object Object]"
}
function isString(object) {
return type.call(object) === "[object String]"
}
var isArray = Array.isArray || function (object) {
return type.call(object) === "[object Array]"
}
function noop() {}
var voidElements = {
AREA: 1,
BASE: 1,
BR: 1,
COL: 1,
COMMAND: 1,
EMBED: 1,
HR: 1,
IMG: 1,
INPUT: 1,
KEYGEN: 1,
LINK: 1,
META: 1,
PARAM: 1,
SOURCE: 1,
TRACK: 1,
WBR: 1
}
// caching commonly used variables
var $document, $location, $requestAnimationFrame, $cancelAnimationFrame
// self invoking function needed because of the way mocks work
function initialize(mock) {
$document = mock.document
$location = mock.location
$cancelAnimationFrame = mock.cancelAnimationFrame || mock.clearTimeout
$requestAnimationFrame = mock.requestAnimationFrame || mock.setTimeout
}
// testing API
m.deps = function (mock) {
initialize(global = mock || window)
return global
}
m.deps(global)
/**
* @typedef {String} Tag
* A string that looks like -> div.classname#id[param=one][param2=two]
* Which describes a DOM node
*/
function parseTagAttrs(cell, tag) {
var classes = []
var parser = /(?:(^|#|\.)([^#\.\[\]]+))|(\[.+?\])/g
var match
while ((match = parser.exec(tag))) {
if (match[1] === "" && match[2]) {
cell.tag = match[2]
} else if (match[1] === "#") {
cell.attrs.id = match[2]
} else if (match[1] === ".") {
classes.push(match[2])
} else if (match[3][0] === "[") {
var pair = /\[(.+?)(?:=("|'|)(.*?)\2)?\]/.exec(match[3])
cell.attrs[pair[1]] = pair[3] || ""
}
}
return classes
}
function getVirtualChildren(args, hasAttrs) {
var children = hasAttrs ? args.slice(1) : args
if (children.length === 1 && isArray(children[0])) {
return children[0]
} else {
return children
}
}
function assignAttrs(target, attrs, classes) {
var classAttr = "class" in attrs ? "class" : "className"
for (var attrName in attrs) {
if (hasOwn.call(attrs, attrName)) {
if (attrName === classAttr &&
attrs[attrName] != null &&
attrs[attrName] !== "") {
classes.push(attrs[attrName])
// create key in correct iteration order
target[attrName] = ""
} else {
target[attrName] = attrs[attrName]
}
}
}
if (classes.length) target[classAttr] = classes.join(" ")
}
/**
*
* @param {Tag} The DOM node tag
* @param {Object=[]} optional key-value pairs to be mapped to DOM attrs
* @param {...mNode=[]} Zero or more Mithril child nodes. Can be an array,
* or splat (optional)
*/
function m(tag, pairs) {
var args = []
for (var i = 1, length = arguments.length; i < length; i++) {
args[i - 1] = arguments[i]
}
if (isObject(tag)) return parameterize(tag, args)
if (!isString(tag)) {
throw new Error("selector in m(selector, attrs, children) should " +
"be a string")
}
var hasAttrs = pairs != null && isObject(pairs) &&
!("tag" in pairs || "view" in pairs || "subtree" in pairs)
var attrs = hasAttrs ? pairs : {}
var cell = {
tag: "div",
attrs: {},
children: getVirtualChildren(args, hasAttrs)
}
assignAttrs(cell.attrs, attrs, parseTagAttrs(cell, tag))
return cell
}
function forEach(list, f) {
for (var i = 0; i < list.length && !f(list[i], i++);) {
// function called in condition
}
}
function forKeys(list, f) {
forEach(list, function (attrs, i) {
return (attrs = attrs && attrs.attrs) &&
attrs.key != null &&
f(attrs, i)
})
}
// This function was causing deopts in Chrome.
function dataToString(data) {
// data.toString() might throw or return null if data is the return
// value of Console.log in some versions of Firefox (behavior depends on
// version)
try {
if (data != null && data.toString() != null) return data
} catch (e) {
// silently ignore errors
}
return ""
}
// This function was causing deopts in Chrome.
function injectTextNode(parentElement, first, index, data) {
try {
insertNode(parentElement, first, index)
first.nodeValue = data
} catch (e) {
// IE erroneously throws error when appending an empty text node
// after a null
}
}
function flatten(list) {
// recursively flatten array
for (var i = 0; i < list.length; i++) {
if (isArray(list[i])) {
list = list.concat.apply([], list)
// check current index again and flatten until there are no more
// nested arrays at that index
i--
}
}
return list
}
function insertNode(parentElement, node, index) {
parentElement.insertBefore(node,
parentElement.childNodes[index] || null)
}
var DELETION = 1
var INSERTION = 2
var MOVE = 3
function handleKeysDiffer(data, existing, cached, parentElement) {
forKeys(data, function (key, i) {
existing[key = key.key] = existing[key] ? {
action: MOVE,
index: i,
from: existing[key].index,
element: cached.nodes[existing[key].index] ||
$document.createElement("div")
} : {action: INSERTION, index: i}
})
var actions = []
for (var prop in existing) {
if (hasOwn.call(existing, prop)) {
actions.push(existing[prop])
}
}
var changes = actions.sort(sortChanges)
var newCached = new Array(cached.length)
newCached.nodes = cached.nodes.slice()
forEach(changes, function (change) {
var index = change.index
if (change.action === DELETION) {
clear(cached[index].nodes, cached[index])
newCached.splice(index, 1)
}
if (change.action === INSERTION) {
var dummy = $document.createElement("div")
dummy.key = data[index].attrs.key
insertNode(parentElement, dummy, index)
newCached.splice(index, 0, {
attrs: {key: data[index].attrs.key},
nodes: [dummy]
})
newCached.nodes[index] = dummy
}
if (change.action === MOVE) {
var changeElement = change.element
var maybeChanged = parentElement.childNodes[index]
if (maybeChanged !== changeElement && changeElement !== null) {
parentElement.insertBefore(changeElement,
maybeChanged || null)
}
newCached[index] = cached[change.from]
newCached.nodes[index] = changeElement
}
})
return newCached
}
function diffKeys(data, cached, existing, parentElement) {
var keysDiffer = data.length !== cached.length
if (!keysDiffer) {
forKeys(data, function (attrs, i) {
var cachedCell = cached[i]
return keysDiffer = cachedCell &&
cachedCell.attrs &&
cachedCell.attrs.key !== attrs.key
})
}
if (keysDiffer) {
return handleKeysDiffer(data, existing, cached, parentElement)
} else {
return cached
}
}
function diffArray(data, cached, nodes) {
// diff the array itself
// update the list of DOM nodes by collecting the nodes from each item
forEach(data, function (_, i) {
if (cached[i] != null) nodes.push.apply(nodes, cached[i].nodes)
})
// remove items from the end of the array if the new array is shorter
// than the old one. if errors ever happen here, the issue is most
// likely a bug in the construction of the `cached` data structure
// somewhere earlier in the program
forEach(cached.nodes, function (node, i) {
if (node.parentNode != null && nodes.indexOf(node) < 0) {
clear([node], [cached[i]])
}
})
if (data.length < cached.length) cached.length = data.length
cached.nodes = nodes
}
function buildArrayKeys(data) {
var guid = 0
forKeys(data, function () {
forEach(data, function (attrs) {
if ((attrs = attrs && attrs.attrs) && attrs.key == null) {
attrs.key = "__mithril__" + guid++
}
})
return 1
})
}
function isDifferentEnough(data, cached, dataAttrKeys) {
if (data.tag !== cached.tag) return true
if (dataAttrKeys.sort().join() !==
Object.keys(cached.attrs).sort().join()) {
return true
}
if (data.attrs.id !== cached.attrs.id) {
return true
}
if (data.attrs.key !== cached.attrs.key) {
return true
}
if (m.redraw.strategy() === "all") {
return !cached.configContext || cached.configContext.retain !== true
}
if (m.redraw.strategy() === "diff") {
return cached.configContext && cached.configContext.retain === false
}
return false
}
function maybeRecreateObject(data, cached, dataAttrKeys) {
// if an element is different enough from the one in cache, recreate it
if (isDifferentEnough(data, cached, dataAttrKeys)) {
if (cached.nodes.length) clear(cached.nodes)
if (cached.configContext &&
isFunction(cached.configContext.onunload)) {
cached.configContext.onunload()
}
if (cached.controllers) {
forEach(cached.controllers, function (controller) {
if (controller.onunload) {
controller.onunload({preventDefault: noop})
}
})
}
}
}
function getObjectNamespace(data, namespace) {
if (data.attrs.xmlns) return data.attrs.xmlns
if (data.tag === "svg") return "http://www.w3.org/2000/svg"
if (data.tag === "math") return "http://www.w3.org/1998/Math/MathML"
return namespace
}
var pendingRequests = 0
m.startComputation = function () { pendingRequests++ }
m.endComputation = function () {
if (pendingRequests > 1) {
pendingRequests--
} else {
pendingRequests = 0
m.redraw()
}
}
function unloadCachedControllers(cached, views, controllers) {
if (controllers.length) {
cached.views = views
cached.controllers = controllers
forEach(controllers, function (controller) {
if (controller.onunload && controller.onunload.$old) {
controller.onunload = controller.onunload.$old
}
if (pendingRequests && controller.onunload) {
var onunload = controller.onunload
controller.onunload = noop
controller.onunload.$old = onunload
}
})
}
}
function scheduleConfigsToBeCalled(configs, data, node, isNew, cached) {
// schedule configs to be called. They are called after `build` finishes
// running
if (isFunction(data.attrs.config)) {
var context = cached.configContext = cached.configContext || {}
// bind
configs.push(function () {
return data.attrs.config.call(data, node, !isNew, context,
cached)
})
}
}
function buildUpdatedNode(
cached,
data,
editable,
hasKeys,
namespace,
views,
configs,
controllers
) {
var node = cached.nodes[0]
if (hasKeys) {
setAttributes(node, data.tag, data.attrs, cached.attrs, namespace)
}
cached.children = build(
node,
data.tag,
undefined,
undefined,
data.children,
cached.children,
false,
0,
data.attrs.contenteditable ? node : editable,
namespace,
configs
)
cached.nodes.intact = true
if (controllers.length) {
cached.views = views
cached.controllers = controllers
}
return node
}
function handleNonexistentNodes(data, parentElement, index) {
var nodes
if (data.$trusted) {
nodes = injectHTML(parentElement, index, data)
} else {
nodes = [$document.createTextNode(data)]
if (!(parentElement.nodeName in voidElements)) {
insertNode(parentElement, nodes[0], index)
}
}
var cached
if (typeof data === "string" ||
typeof data === "number" ||
typeof data === "boolean") {
cached = new data.constructor(data)
} else {
cached = data
}
cached.nodes = nodes
return cached
}
function reattachNodes(
data,
cached,
parentElement,
editable,
index,
parentTag
) {
var nodes = cached.nodes
if (!editable || editable !== $document.activeElement) {
if (data.$trusted) {
clear(nodes, cached)
nodes = injectHTML(parentElement, index, data)
} else if (parentTag === "textarea") {
// <textarea> uses `value` instead of `nodeValue`.
parentElement.value = data
} else if (editable) {
// contenteditable nodes use `innerHTML` instead of `nodeValue`.
editable.innerHTML = data
} else {
// was a trusted string
if (nodes[0].nodeType === 1 || nodes.length > 1 ||
(nodes[0].nodeValue.trim &&
!nodes[0].nodeValue.trim())) {
clear(cached.nodes, cached)
nodes = [$document.createTextNode(data)]
}
injectTextNode(parentElement, nodes[0], index, data)
}
}
cached = new data.constructor(data)
cached.nodes = nodes
return cached
}
function handleTextNode(
cached,
data,
index,
parentElement,
shouldReattach,
editable,
parentTag
) {
if (!cached.nodes.length) {
return handleNonexistentNodes(data, parentElement, index)
} else if (cached.valueOf() !== data.valueOf() || shouldReattach) {
return reattachNodes(data, cached, parentElement, editable, index,
parentTag)
} else {
return (cached.nodes.intact = true, cached)
}
}
function getSubArrayCount(item) {
if (item.$trusted) {
// fix offset of next element if item was a trusted string w/ more
// than one html element
// the first clause in the regexp matches elements
// the second clause (after the pipe) matches text nodes
var match = item.match(/<[^\/]|\>\s*[^<]/g)
if (match != null) return match.length
} else if (isArray(item)) {
return item.length
}
return 1
}
function buildArray(
data,
cached,
parentElement,
index,
parentTag,
shouldReattach,
editable,
namespace,
configs
) {
data = flatten(data)
var nodes = []
var intact = cached.length === data.length
var subArrayCount = 0
// keys algorithm: sort elements without recreating them if keys are
// present
//
// 1) create a map of all existing keys, and mark all for deletion
// 2) add new keys to map and mark them for addition
// 3) if key exists in new list, change action from deletion to a move
// 4) for each key, handle its corresponding action as marked in
// previous steps
var existing = {}
var shouldMaintainIdentities = false
forKeys(cached, function (attrs, i) {
shouldMaintainIdentities = true
existing[cached[i].attrs.key] = {action: DELETION, index: i}
})
buildArrayKeys(data)
if (shouldMaintainIdentities) {
cached = diffKeys(data, cached, existing, parentElement)
}
// end key algorithm
var cacheCount = 0
// faster explicitly written
for (var i = 0, len = data.length; i < len; i++) {
// diff each item in the array
var item = build(
parentElement,
parentTag,
cached,
index,
data[i],
cached[cacheCount],
shouldReattach,
index + subArrayCount || subArrayCount,
editable,
namespace,
configs)
if (item !== undefined) {
intact = intact && item.nodes.intact
subArrayCount += getSubArrayCount(item)
cached[cacheCount++] = item
}
}
if (!intact) diffArray(data, cached, nodes)
return cached
}
function makeCache(data, cached, index, parentIndex, parentCache) {
if (cached != null) {
if (type.call(cached) === type.call(data)) return cached
if (parentCache && parentCache.nodes) {
var offset = index - parentIndex
var end = offset + (isArray(data) ? data : cached.nodes).length
clear(
parentCache.nodes.slice(offset, end),
parentCache.slice(offset, end))
} else if (cached.nodes) {
clear(cached.nodes, cached)
}
}
cached = new data.constructor()
// if constructor creates a virtual dom element, use a blank object as
// the base cached node instead of copying the virtual el (#277)
if (cached.tag) cached = {}
cached.nodes = []
return cached
}
function constructNode(data, namespace) {
if (data.attrs.is) {
if (namespace == null) {
return $document.createElement(data.tag, data.attrs.is)
} else {
return $document.createElementNS(namespace, data.tag,
data.attrs.is)
}
} else if (namespace == null) {
return $document.createElement(data.tag)
} else {
return $document.createElementNS(namespace, data.tag)
}
}
function constructAttrs(data, node, namespace, hasKeys) {
if (hasKeys) {
return setAttributes(node, data.tag, data.attrs, {}, namespace)
} else {
return data.attrs
}
}
function constructChildren(
data,
node,
cached,
editable,
namespace,
configs
) {
if (data.children != null && data.children.length > 0) {
return build(
node,
data.tag,
undefined,
undefined,
data.children,
cached.children,
true,
0,
data.attrs.contenteditable ? node : editable,
namespace,
configs)
} else {
return data.children
}
}
function reconstructCached(
data,
attrs,
children,
node,
namespace,
views,
controllers
) {
var cached = {
tag: data.tag,
attrs: attrs,
children: children,
nodes: [node]
}
unloadCachedControllers(cached, views, controllers)
if (cached.children && !cached.children.nodes) {
cached.children.nodes = []
}
// edge case: setting value on <select> doesn't work before children
// exist, so set it again after children have been created
if (data.tag === "select" && "value" in data.attrs) {
setAttributes(node, data.tag, {value: data.attrs.value}, {},
namespace)
}
return cached
}
function getController(views, view, cachedControllers, controller) {
var controllerIndex
if (m.redraw.strategy() === "diff" && views) {
controllerIndex = views.indexOf(view)
} else {
controllerIndex = -1
}
if (controllerIndex > -1) {
return cachedControllers[controllerIndex]
} else if (isFunction(controller)) {
return new controller()
} else {
return {}
}
}
var unloaders = []
function updateLists(views, controllers, view, controller) {
if (controller.onunload != null &&
unloaders.map(function (u) { return u.handler })
.indexOf(controller.onunload) < 0) {
unloaders.push({
controller: controller,
handler: controller.onunload
})
}
views.push(view)
controllers.push(controller)
}
var forcing = false
function checkView(
data,
view,
cached,
cachedControllers,
controllers,
views
) {
var controller = getController(
cached.views,
view,
cachedControllers,
data.controller)
var key = data && data.attrs && data.attrs.key
if (pendingRequests === 0 ||
forcing ||
cachedControllers &&
cachedControllers.indexOf(controller) > -1) {
data = data.view(controller)
} else {
data = {tag: "placeholder"}
}
if (data.subtree === "retain") return data
data.attrs = data.attrs || {}
data.attrs.key = key
updateLists(views, controllers, view, controller)
return data
}
function markViews(data, cached, views, controllers) {
var cachedControllers = cached && cached.controllers
while (data.view != null) {
data = checkView(
data,
data.view.$original || data.view,
cached,
cachedControllers,
controllers,
views)
}
return data
}
function buildObject( // eslint-disable-line max-statements
data,
cached,
editable,
parentElement,
index,
shouldReattach,
namespace,
configs
) {
var views = []
var controllers = []
data = markViews(data, cached, views, controllers)
if (data.subtree === "retain") return cached
if (!data.tag && controllers.length) {
throw new Error("Component template must return a virtual " +
"element, not an array, string, etc.")
}
data.attrs = data.attrs || {}
cached.attrs = cached.attrs || {}
var dataAttrKeys = Object.keys(data.attrs)
var hasKeys = dataAttrKeys.length > ("key" in data.attrs ? 1 : 0)
maybeRecreateObject(data, cached, dataAttrKeys)
if (!isString(data.tag)) return
var isNew = cached.nodes.length === 0
namespace = getObjectNamespace(data, namespace)
var node
if (isNew) {
node = constructNode(data, namespace)
// set attributes first, then create children
var attrs = constructAttrs(data, node, namespace, hasKeys)
// add the node to its parent before attaching children to it
insertNode(parentElement, node, index)
var children = constructChildren(data, node, cached, editable,
namespace, configs)
cached = reconstructCached(
data,
attrs,
children,
node,
namespace,
views,
controllers)
} else {
node = buildUpdatedNode(
cached,
data,
editable,
hasKeys,
namespace,
views,
configs,
controllers)
}
if (!isNew && shouldReattach === true && node != null) {
insertNode(parentElement, node, index)
}
// The configs are called after `build` finishes running
scheduleConfigsToBeCalled(configs, data, node, isNew, cached)
return cached
}
function build(
parentElement,
parentTag,
parentCache,
parentIndex,
data,
cached,
shouldReattach,
index,
editable,
namespace,
configs
) {
/*
* `build` is a recursive function that manages creation/diffing/removal
* of DOM elements based on comparison between `data` and `cached` the
* diff algorithm can be summarized as this:
*
* 1 - compare `data` and `cached`
* 2 - if they are different, copy `data` to `cached` and update the DOM
* based on what the difference is
* 3 - recursively apply this algorithm for every array and for the
* children of every virtual element
*
* The `cached` data structure is essentially the same as the previous
* redraw's `data` data structure, with a few additions:
* - `cached` always has a property called `nodes`, which is a list of
* DOM elements that correspond to the data represented by the
* respective virtual element
* - in order to support attaching `nodes` as a property of `cached`,
* `cached` is *always* a non-primitive object, i.e. if the data was
* a string, then cached is a String instance. If data was `null` or
* `undefined`, cached is `new String("")`
* - `cached also has a `configContext` property, which is the state
* storage object exposed by config(element, isInitialized, context)
* - when `cached` is an Object, it represents a virtual element; when
* it's an Array, it represents a list of elements; when it's a
* String, Number or Boolean, it represents a text node
*
* `parentElement` is a DOM element used for W3C DOM API calls
* `parentTag` is only used for handling a corner case for textarea
* values
* `parentCache` is used to remove nodes in some multi-node cases
* `parentIndex` and `index` are used to figure out the offset of nodes.
* They're artifacts from before arrays started being flattened and are
* likely refactorable
* `data` and `cached` are, respectively, the new and old nodes being
* diffed
* `shouldReattach` is a flag indicating whether a parent node was
* recreated (if so, and if this node is reused, then this node must
* reattach itself to the new parent)
* `editable` is a flag that indicates whether an ancestor is
* contenteditable
* `namespace` indicates the closest HTML namespace as it cascades down
* from an ancestor
* `configs` is a list of config functions to run after the topmost
* `build` call finishes running
*
* there's logic that relies on the assumption that null and undefined
* data are equivalent to empty strings
* - this prevents lifecycle surprises from procedural helpers that mix
* implicit and explicit return statements (e.g.
* function foo() {if (cond) return m("div")}
* - it simplifies diffing code
*/
data = dataToString(data)
if (data.subtree === "retain") return cached
cached = makeCache(data, cached, index, parentIndex, parentCache)
if (isArray(data)) {
return buildArray(
data,
cached,
parentElement,
index,
parentTag,
shouldReattach,
editable,
namespace,
configs)
} else if (data != null && isObject(data)) {
return buildObject(
data,
cached,
editable,
parentElement,
index,
shouldReattach,
namespace,
configs)
} else if (!isFunction(data)) {
return handleTextNode(
cached,
data,
index,
parentElement,
shouldReattach,
editable,
parentTag)
} else {
return cached