Returned tuples don't match compatible types when using function union types

The first error is especially odd.

TypeScript Version: 3.7.x-dev.20200104

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Code

type C1 = (a: 1) => [0];
type C2 = (a: 2) => [number];
type C3 = (a: 3) => undefined;

declare function f(a: C1 | C3): void;
f(() => [0]);
declare function g(a: C2 | C3): void;
g(() => [0]);

Expected behavior: pass Actual behavior: Type ‘number’ is not assignable to type ‘0’.(2322) Property ‘0’ is missing in type ‘number[]’ but required in type ‘[number]’.(2741) Playground Link: http://www.typescriptlang.org/play/index.html?ts=3.8.0-dev.20200104&ssl=1&ssc=1&pln=8&pc=14#code/C4TwDgpgBAwgjFAvFAFAQwFxTgSiQPigG0AGAXQG4AoUSWAJiVUynr0UKIDsBXAWwBGEAE6Ua4aDADMTdFintCPLgBMIAMwCWXCCupU1AYwA2aYdHXLDwTQHsuUdXNgIAPrAVYAbrc16qTiiKxOQ41Eam5o5WNvZQAObOMIzu0jjevv6JQQQhZGFAA

Related Issues:

[falsandtru]

@jcalz Your stupid comments are really useless and annoying. Don’t touch my issues. I’m not posting issues to talk to you.

[jcalz]

Magic? (No, I’m not sure.)