TypeScript/tests/baselines/reference/controlFlowAliasing.errors.txt

tests/cases/conformance/controlFlow/controlFlowAliasing.ts(59,13): error TS2322: Type 'string | number' is not assignable to type 'string'.
  Type 'number' is not assignable to type 'string'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(74,13): error TS2322: Type 'string | number' is not assignable to type 'string'.
  Type 'number' is not assignable to type 'string'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(91,13): error TS2339: Property 'foo' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
  Property 'foo' does not exist on type '{ kind: "bar"; bar: number; }'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(94,13): error TS2339: Property 'bar' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
  Property 'bar' does not exist on type '{ kind: "foo"; foo: string; }'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(101,13): error TS2339: Property 'foo' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
  Property 'foo' does not exist on type '{ kind: "bar"; bar: number; }'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(104,13): error TS2339: Property 'bar' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
  Property 'bar' does not exist on type '{ kind: "foo"; foo: string; }'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(112,13): error TS2339: Property 'foo' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
  Property 'foo' does not exist on type '{ kind: "bar"; bar: number; }'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(115,13): error TS2339: Property 'bar' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
  Property 'bar' does not exist on type '{ kind: "foo"; foo: string; }'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(134,13): error TS2339: Property 'foo' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
  Property 'foo' does not exist on type '{ kind: "bar"; bar: number; }'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(137,13): error TS2339: Property 'bar' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
  Property 'bar' does not exist on type '{ kind: "foo"; foo: string; }'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(154,19): error TS2339: Property 'foo' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
  Property 'foo' does not exist on type '{ kind: "bar"; bar: number; }'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(157,19): error TS2339: Property 'bar' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
  Property 'bar' does not exist on type '{ kind: "foo"; foo: string; }'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(219,13): error TS2322: Type 'string | number' is not assignable to type 'string'.
  Type 'number' is not assignable to type 'string'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(232,13): error TS2322: Type 'string | number' is not assignable to type 'string'.
  Type 'number' is not assignable to type 'string'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(233,13): error TS2322: Type 'string | number' is not assignable to type 'string'.
  Type 'number' is not assignable to type 'string'.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(280,5): error TS2448: Block-scoped variable 'a' used before its declaration.
tests/cases/conformance/controlFlow/controlFlowAliasing.ts(280,5): error TS2454: Variable 'a' is used before being assigned.


==== tests/cases/conformance/controlFlow/controlFlowAliasing.ts (17 errors) ====
    // Narrowing by aliased conditional expressions
    
    function f10(x: string | number) {
        const isString = typeof x === "string";
        if (isString) {
            let t: string = x;
        }
        else {
            let t: number = x;
        }
    }
    
    function f11(x: unknown) {
        const isString = typeof x === "string";
        if (isString) {
            let t: string = x;
        }
    }
    
    function f12(x: string | number | boolean) {
        const isString = typeof x === "string";
        const isNumber = typeof x === "number";
        if (isString || isNumber) {
            let t: string | number = x;
        }
        else {
            let t: boolean = x;
        }
    }
    
    function f13(x: string | number | boolean) {
        const isString = typeof x === "string";
        const isNumber = typeof x === "number";
        const isStringOrNumber = isString || isNumber;
        if (isStringOrNumber) {
            let t: string | number = x;
        }
        else {
            let t: boolean = x;
        }
    }
    
    function f14(x: number | null | undefined): number | null {
        const notUndefined = x !== undefined;
        return notUndefined ? x : 0;
    }
    
    function f15(obj: { readonly x: string | number }) {
        const isString = typeof obj.x === 'string';
        if (isString) {
            let s: string = obj.x;
        }
    }
    
    function f16(obj: { readonly x: string | number }) {
        const isString = typeof obj.x === 'string';
        obj = { x: 42 };
        if (isString) {
            let s: string = obj.x;  // Not narrowed because of is assigned in function body
                ~
!!! error TS2322: Type 'string | number' is not assignable to type 'string'.
!!! error TS2322:   Type 'number' is not assignable to type 'string'.
        }
    }
    
    function f17(obj: readonly [string | number]) {
        const isString = typeof obj[0] === 'string';
        if (isString) {
            let s: string = obj[0];
        }
    }
    
    function f18(obj: readonly [string | number]) {
        const isString = typeof obj[0] === 'string';
        obj = [42];
        if (isString) {
            let s: string = obj[0];  // Not narrowed because of is assigned in function body
                ~
!!! error TS2322: Type 'string | number' is not assignable to type 'string'.
!!! error TS2322:   Type 'number' is not assignable to type 'string'.
        }
    }
    
    function f20(obj: { kind: 'foo', foo: string } | { kind: 'bar', bar: number }) {
        const isFoo = obj.kind === 'foo';
        if (isFoo) {
            obj.foo;
        }
        else {
            obj.bar;
        }
    }
    
    function f21(obj: { kind: 'foo', foo: string } | { kind: 'bar', bar: number }) {
        const isFoo: boolean = obj.kind === 'foo';
        if (isFoo) {
            obj.foo;  // Not narrowed because isFoo has type annotation
                ~~~
!!! error TS2339: Property 'foo' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
!!! error TS2339:   Property 'foo' does not exist on type '{ kind: "bar"; bar: number; }'.
        }
        else {
            obj.bar;  // Not narrowed because isFoo has type annotation
                ~~~
!!! error TS2339: Property 'bar' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
!!! error TS2339:   Property 'bar' does not exist on type '{ kind: "foo"; foo: string; }'.
        }
    }
    
    function f22(obj: { kind: 'foo', foo: string } | { kind: 'bar', bar: number }) {
        let isFoo = obj.kind === 'foo';
        if (isFoo) {
            obj.foo;  // Not narrowed because isFoo is mutable
                ~~~
!!! error TS2339: Property 'foo' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
!!! error TS2339:   Property 'foo' does not exist on type '{ kind: "bar"; bar: number; }'.
        }
        else {
            obj.bar;  // Not narrowed because isFoo is mutable
                ~~~
!!! error TS2339: Property 'bar' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
!!! error TS2339:   Property 'bar' does not exist on type '{ kind: "foo"; foo: string; }'.
        }
    }
    
    function f23(obj: { kind: 'foo', foo: string } | { kind: 'bar', bar: number }) {
        const isFoo = obj.kind === 'foo';
        obj = obj;
        if (isFoo) {
            obj.foo;  // Not narrowed because obj is assigned in function body
                ~~~
!!! error TS2339: Property 'foo' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
!!! error TS2339:   Property 'foo' does not exist on type '{ kind: "bar"; bar: number; }'.
        }
        else {
            obj.bar;  // Not narrowed because obj is assigned in function body
                ~~~
!!! error TS2339: Property 'bar' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
!!! error TS2339:   Property 'bar' does not exist on type '{ kind: "foo"; foo: string; }'.
        }
    }
    
    function f24(arg: { kind: 'foo', foo: string } | { kind: 'bar', bar: number }) {
        const obj = arg;
        const isFoo = obj.kind === 'foo';
        if (isFoo) {
            obj.foo;
        }
        else {
            obj.bar;
        }
    }
    
    function f25(arg: { kind: 'foo', foo: string } | { kind: 'bar', bar: number }) {
        let obj = arg;
        const isFoo = obj.kind === 'foo';
        if (isFoo) {
            obj.foo;  // Not narrowed because obj is mutable
                ~~~
!!! error TS2339: Property 'foo' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
!!! error TS2339:   Property 'foo' does not exist on type '{ kind: "bar"; bar: number; }'.
        }
        else {
            obj.bar;  // Not narrowed because obj is mutable
                ~~~
!!! error TS2339: Property 'bar' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
!!! error TS2339:   Property 'bar' does not exist on type '{ kind: "foo"; foo: string; }'.
        }
    }
    
    function f26(outer: { readonly obj: { kind: 'foo', foo: string } | { kind: 'bar', bar: number } }) {
        const isFoo = outer.obj.kind === 'foo';
        if (isFoo) {
            outer.obj.foo;
        }
        else {
            outer.obj.bar;
        }
    }
    
    function f27(outer: { obj: { kind: 'foo', foo: string } | { kind: 'bar', bar: number } }) {
        const isFoo = outer.obj.kind === 'foo';
        if (isFoo) {
            outer.obj.foo;  // Not narrowed because obj is mutable
                      ~~~
!!! error TS2339: Property 'foo' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
!!! error TS2339:   Property 'foo' does not exist on type '{ kind: "bar"; bar: number; }'.
        }
        else {
            outer.obj.bar;  // Not narrowed because obj is mutable
                      ~~~
!!! error TS2339: Property 'bar' does not exist on type '{ kind: "foo"; foo: string; } | { kind: "bar"; bar: number; }'.
!!! error TS2339:   Property 'bar' does not exist on type '{ kind: "foo"; foo: string; }'.
        }
    }
    
    function f28(obj?: { kind: 'foo', foo: string } | { kind: 'bar', bar: number }) {
        const isFoo = obj && obj.kind === 'foo';
        const isBar = obj && obj.kind === 'bar';
        if (isFoo) {
            obj.foo;
        }
        if (isBar) {
            obj.bar;
        }
    }
    
    // Narrowing by aliased discriminant property access
    
    function f30(obj: { kind: 'foo', foo: string } | { kind: 'bar', bar: number }) {
        const kind = obj.kind;
        if (kind === 'foo') {
            obj.foo;
        }
        else {
            obj.bar;
        }
    }
    
    function f31(obj: { kind: 'foo', foo: string } | { kind: 'bar', bar: number }) {
        const { kind } = obj;
        if (kind === 'foo') {
            obj.foo;
        }
        else {
            obj.bar;
        }
    }
    
    function f32(obj: { kind: 'foo', foo: string } | { kind: 'bar', bar: number }) {
        const { kind: k } = obj;
        if (k === 'foo') {
            obj.foo;
        }
        else {
            obj.bar;
        }
    }
    
    function f33(obj: { kind: 'foo', foo: string } | { kind: 'bar', bar: number }) {
        const { kind } = obj;
        switch (kind) {
            case 'foo': obj.foo; break;
            case 'bar': obj.bar; break;
        }
    }
    
    
    class C10 {
        constructor(readonly x: string | number) {
            const thisX_isString = typeof this.x === 'string';
            const xIsString = typeof x === 'string';
            if (thisX_isString && xIsString) {
                let s: string;
                s = this.x;
                ~
!!! error TS2322: Type 'string | number' is not assignable to type 'string'.
!!! error TS2322:   Type 'number' is not assignable to type 'string'.
                s = x;
            }
        }
    }
    
    class C11 {
        constructor(readonly x: string | number) {
            const thisX_isString = typeof this.x === 'string';
            const xIsString = typeof x === 'string';
            if (thisX_isString && xIsString) {
                // Some narrowings may be invalidated due to later assignments.
                let s: string;
                s = this.x;
                ~
!!! error TS2322: Type 'string | number' is not assignable to type 'string'.
!!! error TS2322:   Type 'number' is not assignable to type 'string'.
                s = x;
                ~
!!! error TS2322: Type 'string | number' is not assignable to type 'string'.
!!! error TS2322:   Type 'number' is not assignable to type 'string'.
            }
            else {
                this.x = 10;
                x = 10;
            }
        }
    }
    
    // Mixing of aliased discriminants and conditionals
    
    function f40(obj: { kind: 'foo', foo?: string } | { kind: 'bar', bar?: number }) {
        const { kind } = obj;
        const isFoo = kind == 'foo';
        if (isFoo && obj.foo) {
            let t: string = obj.foo;
        }
    }
    
    // Unsupported narrowing of destructured payload by destructured discriminant
    
    type Data = { kind: 'str', payload: string } | { kind: 'num', payload: number };
    
    function gg2(obj: Data) {
        if (obj.kind === 'str') {
            let t: string = obj.payload;
        }
        else {
            let t: number = obj.payload;
        }
    }
    
    function foo({ kind, payload }: Data) {
        if (kind === 'str') {
            let t: string = payload;
        }
        else {
            let t: number = payload;
        }
    }
    
    // Repro from #45830
    
    const obj = {
        fn: () => true
    };
    
    if (a) { }
        ~
!!! error TS2448: Block-scoped variable 'a' used before its declaration.
!!! related TS2728 tests/cases/conformance/controlFlow/controlFlowAliasing.ts:282:7: 'a' is declared here.
        ~
!!! error TS2454: Variable 'a' is used before being assigned.
    
    const a = obj.fn();