45 lines
1.1 KiB
JavaScript
Executable file
45 lines
1.1 KiB
JavaScript
Executable file
'use strict';
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const mimicFn = require('mimic-fn');
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const calledFunctions = new WeakMap();
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const onetime = (function_, options = {}) => {
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if (typeof function_ !== 'function') {
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throw new TypeError('Expected a function');
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}
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let returnValue;
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let callCount = 0;
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const functionName = function_.displayName || function_.name || '<anonymous>';
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const onetime = function (...arguments_) {
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calledFunctions.set(onetime, ++callCount);
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if (callCount === 1) {
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returnValue = function_.apply(this, arguments_);
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function_ = null;
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} else if (options.throw === true) {
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throw new Error(`Function \`${functionName}\` can only be called once`);
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}
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return returnValue;
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};
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mimicFn(onetime, function_);
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calledFunctions.set(onetime, callCount);
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return onetime;
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};
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module.exports = onetime;
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// TODO: Remove this for the next major release
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module.exports.default = onetime;
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module.exports.callCount = function_ => {
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if (!calledFunctions.has(function_)) {
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throw new Error(`The given function \`${function_.name}\` is not wrapped by the \`onetime\` package`);
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}
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return calledFunctions.get(function_);
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};
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