66 lines
1.4 KiB
JavaScript
66 lines
1.4 KiB
JavaScript
import {insertBefore, removeChild} from '@riotjs/util/dom'
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/**
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* Binding responsible for the `if` directive
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*/
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export const IfBinding = {
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// dynamic binding properties
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// node: null,
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// evaluate: null,
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// isTemplateTag: false,
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// placeholder: null,
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// template: null,
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// API methods
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mount(scope, parentScope) {
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return this.update(scope, parentScope)
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},
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update(scope, parentScope) {
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const value = !!this.evaluate(scope)
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const mustMount = !this.value && value
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const mustUnmount = this.value && !value
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const mount = () => {
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const pristine = this.node.cloneNode()
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insertBefore(pristine, this.placeholder)
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this.template = this.template.clone()
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this.template.mount(pristine, scope, parentScope)
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}
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switch (true) {
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case mustMount:
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mount()
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break
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case mustUnmount:
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this.unmount(scope)
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break
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default:
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if (value) this.template.update(scope, parentScope)
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}
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this.value = value
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return this
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},
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unmount(scope, parentScope) {
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this.template.unmount(scope, parentScope, true)
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return this
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}
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}
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export default function create(node, { evaluate, template }) {
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const placeholder = document.createTextNode('')
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insertBefore(placeholder, node)
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removeChild(node)
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return {
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...IfBinding,
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node,
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evaluate,
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placeholder,
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template: template.createDOM(node)
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}
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}
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