TypeScript/tests/baselines/reference/exhaustiveSwitchStatements1.errors.txt

tests/cases/conformance/controlFlow/exhaustiveSwitchStatements1.ts(7,9): error TS7027: Unreachable code detected.
tests/cases/conformance/controlFlow/exhaustiveSwitchStatements1.ts(235,5): error TS2367: This condition will always return 'false' since the types '"a" | "b"' and '"c"' have no overlap.


==== tests/cases/conformance/controlFlow/exhaustiveSwitchStatements1.ts (2 errors) ====
    function f1(x: 1 | 2): string {
        if (!!true) {
            switch (x) {
                case 1: return 'a';
                case 2: return 'b';
            }
            x;  // Unreachable
            ~~
!!! error TS7027: Unreachable code detected.
        }
        else {
            throw 0;
        }
    }
    
    function f2(x: 1 | 2) {
        let z: number;
        switch (x) {
            case 1: z = 10; break;
            case 2: z = 20; break;
        }
        z;  // Definitely assigned
    }
    
    function f3(x: 1 | 2) {
        switch (x) {
            case 1: return 10;
            case 2: return 20;
            // Default considered reachable to allow defensive coding
            default: throw new Error("Bad input");
        }
    }
    
    // Repro from #11572
    
    enum E { A, B }
    
    function f(e: E): number {
        switch (e) {
            case E.A: return 0
            case E.B: return 1
        }
    }
    
    function g(e: E): number {
        if (!true)
            return -1
        else
            switch (e) {
                case E.A: return 0
                case E.B: return 1
            }
    }
    
    // Repro from #12668
    
    interface Square { kind: "square"; size: number; }
    
    interface Rectangle { kind: "rectangle"; width: number; height: number; }
    
    interface Circle { kind: "circle"; radius: number; }
    
    interface Triangle { kind: "triangle"; side: number; }
    
    type Shape = Square | Rectangle | Circle | Triangle;
    
    function area(s: Shape): number {
        let area;
        switch (s.kind) {
            case "square": area = s.size * s.size; break;
            case "rectangle": area = s.width * s.height; break;
            case "circle": area = Math.PI * s.radius * s.radius; break;
            case "triangle": area = Math.sqrt(3) / 4 * s.side * s.side; break;
        }
        return area;
    }
    
    function areaWrapped(s: Shape): number {
        let area;
        area = (() => {
            switch (s.kind) {
                case "square": return s.size * s.size;
                case "rectangle": return s.width * s.height;
                case "circle": return Math.PI * s.radius * s.radius;
                case "triangle": return Math.sqrt(3) / 4 * s.side * s.side;
            }
        })();
        return area;
    }
    
    // Repro from #13241
    
    enum MyEnum {
    	A,
    	B
    }
    
    function thisGivesError(e: MyEnum): string {
    	let s: string;
    	switch (e) {
    		case MyEnum.A: s = "it was A"; break;
    		case MyEnum.B: s = "it was B"; break;
    	}
    	return s;
    }
    
    function good1(e: MyEnum): string {
    	let s: string;
    	switch (e) {
    		case MyEnum.A: s = "it was A"; break;
    		case MyEnum.B: s = "it was B"; break;
    		default: s = "it was something else"; break;
    	}
    	return s;
    }
    
    function good2(e: MyEnum): string {
    	switch (e) {
    		case MyEnum.A: return "it was A";
    		case MyEnum.B: return "it was B";
    	}
    }
    
    // Repro from #18362
    
    enum Level {
      One,
      Two,
    }
    
    const doSomethingWithLevel = (level: Level) => {
      let next: Level;
      switch (level) {
        case Level.One:
          next = Level.Two;
          break;
        case Level.Two:
          next = Level.One;
          break;
      }
      return next;
    };
    
    // Repro from #20409
    
    interface Square2 {
        kind: "square";
        size: number;
    }
    
    interface Circle2 {
        kind: "circle";
        radius: number;
    }
    
    type Shape2 = Square2 | Circle2;
    
    function withDefault(s1: Shape2, s2: Shape2): string {
        switch (s1.kind) {
            case "square":
                return "1";
            case "circle":
                switch (s2.kind) {
                    case "square":
                        return "2";
                    case "circle":
                        return "3";
                    default:
                        return "never";
                }
        }
    }
    
    function withoutDefault(s1: Shape2, s2: Shape2): string {
        switch (s1.kind) {
            case "square":
                return "1";
            case "circle":
                switch (s2.kind) {
                    case "square":
                        return "2";
                    case "circle":
                        return "3";
                }
        }
    }
    
    // Repro from #20823
    
    function test4(value: 1 | 2) {
        let x: string;
        switch (value) {
            case 1: x = "one"; break;
            case 2: x = "two"; break;
        }
        return x;
    }
    
    // Repro from #34661
    
    enum Animal { DOG, CAT }
    
    declare const zoo: { animal: Animal } | undefined;
    
    function expression(): Animal {
        switch (zoo?.animal ?? Animal.DOG) {
            case Animal.DOG: return Animal.DOG
            case Animal.CAT: return Animal.CAT
        }
    }
    
    // Repro from #34840
    
    function foo() {
        const foo: number | undefined = 0;
        while (true) {
            const stats = foo;
            switch (stats) {
                case 1: break;
                case 2: break;
            }
        }
    }
    
    // Repro from #35070
    
    type O = {
        a: number,
        b: number
    };
    type K = keyof O | 'c';
    function ff(o: O, k: K) {
        switch(k) {
            case 'c':
                k = 'a';
        }
        k === 'c';  // Error
        ~~~~~~~~~
!!! error TS2367: This condition will always return 'false' since the types '"a" | "b"' and '"c"' have no overlap.
        return o[k];
    }