32 lines
966 B
JavaScript
32 lines
966 B
JavaScript
module.exports = function createEventEmitterProxy (eventEmitter, listeners) {
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let target = eventEmitter
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const eventHandlers = listeners || {}
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const proxy = new Proxy({}, {
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get: (obj, name) => {
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// intercept listeners
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if (name === 'on') return addListener
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if (name === 'setTarget') return setTarget
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if (name === 'proxyEventHandlers') return eventHandlers
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return target[name]
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},
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set: (obj, name, value) => {
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target[name] = value
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return true
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},
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})
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function setTarget (eventEmitter) {
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target = eventEmitter
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// migrate listeners
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Object.keys(eventHandlers).forEach((name) => {
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eventHandlers[name].forEach((handler) => target.on(name, handler))
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})
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}
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function addListener (name, handler) {
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if (!eventHandlers[name]) eventHandlers[name] = []
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eventHandlers[name].push(handler)
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target.on(name, handler)
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}
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if (listeners) proxy.setTarget(eventEmitter)
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return proxy
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}
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