45 lines
1.5 KiB
Plaintext
45 lines
1.5 KiB
Plaintext
==== tests/cases/conformance/types/typeRelationships/subtypesAndSuperTypes/subtypingWithObjectMembersOptionality2.ts (4 errors) ====
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// Derived member is optional but base member is not, should be an error
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interface Base { foo: string; }
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interface Derived extends Base { bar: string; }
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interface T {
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Foo: Base;
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}
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interface S extends T {
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~
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!!! error TS2429: Interface 'S' incorrectly extends interface 'T':
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!!! error TS2429: Required property 'Foo' cannot be reimplemented with optional property in 'S'.
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Foo?: Derived // error
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}
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interface T2 {
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1: Base;
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}
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interface S2 extends T2 {
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~~
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!!! error TS2429: Interface 'S2' incorrectly extends interface 'T2':
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!!! error TS2429: Required property '1' cannot be reimplemented with optional property in 'S2'.
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1?: Derived; // error
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}
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interface T3 {
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'1': Base;
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}
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interface S3 extends T3 {
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~~
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!!! error TS2429: Interface 'S3' incorrectly extends interface 'T3':
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!!! error TS2429: Required property '1' cannot be reimplemented with optional property in 'S3'.
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'1'?: Derived; // error
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}
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// object literal case
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var a: { Foo: Base; }
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var b: { Foo?: Derived; }
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var r = true ? a : b; // error
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~~~~~~~~~~~~
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!!! error TS2367: No best common type exists between '{ Foo: Base; }' and '{ Foo?: Derived; }'. |