37 lines
938 B
TypeScript
37 lines
938 B
TypeScript
import Handlebars from "handlebars"
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export default class Helper {
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private name: any
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private fn: any
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private useValueFallback: boolean
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constructor(name: string, fn: any, useValueFallback = true) {
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this.name = name
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this.fn = fn
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this.useValueFallback = useValueFallback
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}
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register(handlebars: typeof Handlebars) {
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// wrap the function so that no helper can cause handlebars to break
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handlebars.registerHelper(
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this.name,
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(value: any, info: { data: { root: {} } }) => {
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let context = {}
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if (info && info.data && info.data.root) {
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context = info.data.root
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}
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const result = this.fn(value, context)
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if (result == null) {
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return this.useValueFallback ? value : null
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} else {
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return result
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}
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}
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)
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}
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unregister(handlebars: { unregisterHelper: any }) {
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handlebars.unregisterHelper(this.name)
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}
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}
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