89 lines
2 KiB
TypeScript
89 lines
2 KiB
TypeScript
//// [subtypingWithObjectMembersOptionality.ts]
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// Derived member is not optional but base member is, should be ok
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interface Base { foo: string; }
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interface Derived extends Base { bar: string; }
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interface Derived2 extends Derived { baz: string; }
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// S is a subtype of a type T, and T is a supertype of S, if one of the following is true, where S' denotes the apparent type (section 3.8.1) of S:
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// - S' and T are object types and, for each member M in T, one of the following is true:
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// - M is a property and S' contains a property N where
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// M and N have the same name,
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// the type of N is a subtype of that of M,
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// M and N are both public or both private, and
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// if M is a required property, N is also a required property.
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// - M is an optional property and S' contains no property of the same name as M.
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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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Foo: Derived
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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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1: Derived;
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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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'1.': Derived;
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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>null };
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var r = true ? a : b;
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module TwoLevels {
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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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Foo: Derived2
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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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1: Derived2;
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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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'1.': Derived2;
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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: <Derived2>null };
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var r = true ? a : b;
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}
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//// [subtypingWithObjectMembersOptionality.js]
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// Derived member is not optional but base member is, should be ok
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// object literal case
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var a;
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var b = { Foo: null };
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var r = true ? a : b;
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var TwoLevels;
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(function (TwoLevels) {
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// object literal case
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var a;
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var b = { Foo: null };
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var r = true ? a : b;
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})(TwoLevels || (TwoLevels = {}));
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