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30 lines
950 B
TypeScript
30 lines
950 B
TypeScript
// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
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/**
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* Determines whether an object has a property with the specified name.
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* Avoid calling prototype builtin `hasOwnProperty` for two reasons:
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*
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* 1. `hasOwnProperty` is defined on the object as something else:
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*
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* const options = {
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* ending: 'utf8',
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* hasOwnProperty: 'foo'
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* };
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* options.hasOwnProperty('ending') // throws a TypeError
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*
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* 2. The object doesn't inherit from `Object.prototype`:
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*
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* const options = Object.create(null);
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* options.ending = 'utf8';
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* options.hasOwnProperty('ending'); // throws a TypeError
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*
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* @param obj A Object.
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* @param v A property name.
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* @see https://eslint.org/docs/rules/no-prototype-builtins
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*/
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export function hasOwnProperty<T>(obj: T, v: PropertyKey): boolean {
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if (obj == null) {
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return false;
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}
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return Object.prototype.hasOwnProperty.call(obj, v);
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}
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