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stream: fix Writable instanceof for subclasses · nodejs/node@66187fa

2 files changed

lines changed

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@@ -144,6 +144,8 @@ if (typeof Symbol === 'function' && Symbol.hasInstance) {

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value: function(object) {

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if (realHasInstance.call(this, object))

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return true;

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if (this !== Writable)

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return false;

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return object && object._writableState instanceof WritableState;

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}

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@@ -49,3 +49,8 @@ Object.setPrototypeOf(CustomWritable.prototype, Writable.prototype);

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new CustomWritable();

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assert.throws(CustomWritable, /AssertionError: undefined does not inherit from CustomWritable/);

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class OtherCustomWritable extends Writable {}

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assert(!(new OtherCustomWritable() instanceof CustomWritable));

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assert(!(new CustomWritable() instanceof OtherCustomWritable));