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Type narrowing with assertions containing truthy literals

microsoft/typescript#41503·111137·Go·2130 天未动·6 条评论·上游最近活跃 ·池内状态:可认领
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<!-- 🚨 STOP 🚨 STOP 🚨 STOP 🚨 Half of all issues filed here are duplicates, answered in the FAQ, or not appropriate for the bug tracker. Even if you think you've found a *bug*, please read the FAQ first, especially the Common "Bugs" That Aren't Bugs section! Please help us by doing the following steps before logging an issue: * Search: https://github.com/Microsoft/TypeScript/search?type=Issues * Read the FAQ: https://github.com/Microsoft/TypeScript/wiki/FAQ Please fill in the *entire* template below. --> <!-- Please try to reproduce the issue with the latest published version. It may have already been fixed. For npm: `typescript@next` This is also the 'Nightly' version in the playground: http://www.typescriptlang.org/play/?ts=Nightly --> **TypeScript Version:** 4.2.0-dev.20201109 <!-- Search terms you tried before logging this (so others can find this issue more easily) --> **Search Terms:** `type narrowing truthy` `type narrowing assertion` `conditional throw` **Code** ```ts function test(foo?: number) { if (!foo) throw new Error(); return foo.toFixed(); } function testWithLiteralTrue(foo?: number) { if (!foo && true) throw new Error(); return foo.toFixed(); } function testWithTruthyLiteral(foo?: number) { if (!foo && "str") throw new Error(); return foo.toFixed(); // Object is possibly 'undefined'. } ``` **Expected behavior:** In all three functions typescript would know `foo` is a number after the assertion. **Actual behavior:** In the last example, `testWithTruthyLiteral`, typescript complains `foo` may be `undefined`. This is the same behavior for all known truthy values except for literal `true`. **Playground Link:** <!-- A link to a TypeScript Playground "Share" link which demonstrates this behavior --> https://www.typescriptlang.org/play?ts=4.2.0-dev.20201109#code/GYVwdgxgLglg9mABFApgZygRgBTDnAfgC5EwQBbAIxQCcBKRAbwChFEZhFsBCPOBqAAsacAO6kU4gKI0RNbHQDczVohoooIGkj4A6KHABiMAB4oAJguUBfFaEiwEydFABMufMVIVq9Jqo4uXnxEADJQ5BoQFAFhMQlpWTh5JRU2dU1tRD…
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