choo components (#639)

* add components

* example: componentize header

* fix choo SSR

* example: componentize footer

* example: fix footer

* update component cache asserts

* componentize todos

* reorder example dir

* fix example tests

* fix dep check test

* Add garbage collection of unused components

* Apply args when calling identity

* update to new component preview

* update nanocomponent

* fix cache err name

* remove static methods from example

* restore app.emit() function

* public API tests

* offset component cache iteration by 2

* whitelist contents of component folder (#643)

* allow lru number arg

* fix lint typo

example/components/footer/clear-button.js

@@ -0,0 +1,15 @@
+var html = require('bel')
+
+module.exports = deleteCompleted
+
+function deleteCompleted (emit) {
+  return html`
+    <button class="clear-completed" onclick=${deleteAllCompleted}>
+      Clear completed
+    </button>
+  `
+
+  function deleteAllCompleted () {
+    emit('todos:deleteCompleted')
+  }
+}

example/components/footer/filter-button.js

@@ -0,0 +1,18 @@
+var html = require('bel')
+
+module.exports = filterButton
+
+function filterButton (name, filter, currentFilter, emit) {
+  var filterClass = filter === currentFilter
+    ? 'selected'
+    : ''
+
+  var uri = '#' + name.toLowerCase()
+  if (uri === '#all') uri = '/'
+
+  return html`<li>
+    <a href=${uri} class=${filterClass}>
+      ${name}
+    </a>
+  </li>`
+}

example/components/footer/index.js

@@ -0,0 +1,50 @@
+var Component = require('../../../component')
+var html = require('bel')
+
+var clearButton = require('./clear-button')
+var filterButton = require('./filter-button')
+
+module.exports = class Footer extends Component {
+  constructor (name, state, emit) {
+    super(name)
+    this.state = state
+    this.emit = emit
+
+    this.local = this.state.components.footer = {}
+    this.setState()
+  }
+
+  setState () {
+    this.local.rawTodos = this.state.todos.clock
+    this.local.rawHref = this.state.href
+
+    this.local.filter = this.state.href.replace(/^\//, '') || ''
+    this.local.activeCount = this.state.todos.active.length
+    this.local.hasDone = this.state.todos.done.length || null
+  }
+
+  update () {
+    if (this.local.rawTodos !== this.state.todos.clock ||
+      this.local.rawHref !== this.state.href) {
+      this.setState()
+      return true
+    } else {
+      return false
+    }
+  }
+
+  createElement () {
+    return html`<footer class="footer">
+      <span class="todo-count">
+        <strong>${this.local.activeCount}</strong>
+        item${this.state.todos.all === 1 ? '' : 's'} left
+      </span>
+      <ul class="filters">
+        ${filterButton('All', '', this.local.filter, this.emit)}
+        ${filterButton('Active', 'active', this.local.filter, this.emit)}
+        ${filterButton('Completed', 'completed', this.local.filter, this.emit)}
+      </ul>
+      ${this.local.hasDone && clearButton(this.emit)}
+    </footer>`
+  }
+}

example/components/header.js

@@ -0,0 +1,32 @@
+var Component = require('../../component')
+var html = require('bel')
+
+module.exports = class Header extends Component {
+  constructor (name, state, emit) {
+    super(name)
+    this.state = state
+    this.emit = emit
+  }
+
+  update () {
+    return false
+  }
+
+  createElement () {
+    return html`<header class="header">
+      <h1>todos</h1>
+      <input class="new-todo"
+        autofocus
+        placeholder="What needs to be done?"
+        onkeydown=${this.createTodo.bind(this)} />
+    </header>`
+  }
+
+  createTodo (e) {
+    var value = e.target.value
+    if (e.keyCode === 13) {
+      e.target.value = ''
+      this.emit('todos:create', value)
+    }
+  }
+}

example/components/info.js

@@ -0,0 +1,16 @@
+var Component = require('../../component')
+var html = require('bel')
+
+module.exports = class Info extends Component {
+  update () {
+    return false
+  }
+
+  createElement () {
+    return html`<footer class="info">
+      <p>Double-click to edit a todo</p>
+      <p>choo by <a href="https://yoshuawuyts.com/">Yoshua Wuyts</a></p>
+      <p>Created by <a href="http://shuheikagawa.com">Shuhei Kagawa</a></p>
+    </footer>`
+  }
+}

example/components/todos/index.js

@@ -0,0 +1,65 @@
+var Component = require('../../../component')
+var html = require('bel')
+
+var Todo = require('./todo')
+
+module.exports = class Header extends Component {
+  constructor (name, state, emit) {
+    super(name)
+    this.state = state
+    this.emit = emit
+    this.local = this.state.components[name] = {}
+    this.setState()
+  }
+
+  setState () {
+    this.local.rawTodos = this.state.todos.clock
+    this.local.rawHref = this.state.href
+
+    this.local.allDone = this.state.todos.done.length === this.state.todos.all.length
+    this.local.filter = this.state.href.replace(/^\//, '') || ''
+    this.local.todos = this.local.filter === 'completed'
+      ? this.state.todos.done
+      : this.local.filter === 'active'
+        ? this.state.todos.active
+        : this.state.todos.all
+  }
+
+  update () {
+    if (this.local.rawTodos !== this.state.todos.clock ||
+      this.local.rawHref !== this.state.href) {
+      this.setState()
+      return true
+    } else {
+      return false
+    }
+  }
+
+  createElement () {
+    return html`<section class="main">
+      <input
+        class="toggle-all"
+        type="checkbox"
+        checked=${this.local.allDone}
+        onchange=${() => this.toggleAll()}/>
+      <label for="toggle-all" style="display: none;">
+        Mark all as done
+      </label>
+      <ul class="todo-list">
+        ${this.local.todos.map(todo => Todo(todo, this.emit))}
+      </ul>
+    </section>`
+  }
+
+  createTodo (e) {
+    var value = e.target.value
+    if (e.keyCode === 13) {
+      e.target.value = ''
+      this.emit('todos:create', value)
+    }
+  }
+
+  toggleAll () {
+    this.emit('todos:toggleAll')
+  }
+}

example/components/todos/todo.js

@@ -0,0 +1,64 @@
+var html = require('bel')
+
+module.exports = Todo
+
+function Todo (todo, emit) {
+  var clx = classList({ completed: todo.done, editing: todo.editing })
+  return html`
+    <li id=${todo.id} class=${clx}>
+      <div class="view">
+        <input
+          type="checkbox"
+          class="toggle"
+          checked="${todo.done}"
+          onchange=${toggle} />
+        <label ondblclick=${edit}>${todo.name}</label>
+        <button
+          class="destroy"
+          onclick=${destroy}
+        ></button>
+      </div>
+      <input
+        class="edit"
+        value=${todo.name}
+        onkeydown=${handleEditKeydown}
+        onblur=${update} />
+    </li>
+  `
+
+  function toggle (e) {
+    emit('todos:toggle', todo.id)
+  }
+
+  function edit (e) {
+    emit('todos:edit', todo.id)
+  }
+
+  function destroy (e) {
+    emit('todos:delete', todo.id)
+  }
+
+  function update (e) {
+    emit('todos:update', {
+      id: todo.id,
+      editing: false,
+      name: e.target.value
+    })
+  }
+
+  function handleEditKeydown (e) {
+    if (e.keyCode === 13) update(e)              // Enter
+    else if (e.code === 27) emit('todos:unedit') // Escape
+  }
+
+  function classList (classes) {
+    var str = ''
+    var keys = Object.keys(classes)
+    for (var i = 0, len = keys.length; i < len; i++) {
+      var key = keys[i]
+      var val = classes[key]
+      if (val) str += (key + ' ')
+    }
+    return str
+  }
+}