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Test cases to make sure typeguard is defeated in case of function calls

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From spec:
Also note that it is possible to defeat a type guard by calling a function that changes the type of the guarded variable.
This commit is contained in:
Sheetal Nandi 2014-11-05 14:12:29 -08:00
parent e79bec5cbf
commit 2088a89223
3 changed files with 206 additions and 0 deletions
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75
tests/baselines/reference/typeGuardsDefeat.js Normal file
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@ -0,0 +1,75 @@
//// [typeGuardsDefeat.ts]
// Also note that it is possible to defeat a type guard by calling a function that changes the
// type of the guarded variable.
function foo(x: number | string) {
function f() {
x = 10;
}
if (typeof x === "string") {
f();
return x.length; // string
}
else {
return x++; // number
}
}
function foo2(x: number | string) {
if (typeof x === "string") {
return x.length; // string
}
else {
(function f() {
x = 10;
})();
return x++; // number
}
}
function foo3(x: number | string) {
if (typeof x === "string") {
return x.length; // string
}
else {
(() => {
x = 10;
})();
return x++; // number
}
}
//// [typeGuardsDefeat.js]
// Also note that it is possible to defeat a type guard by calling a function that changes the
// type of the guarded variable.
function foo(x) {
function f() {
x = 10;
}
if (typeof x === "string") {
f();
return x.length; // string
}
else {
return x++; // number
}
}
function foo2(x) {
if (typeof x === "string") {
return x.length; // string
}
else {
(function f() {
x = 10;
})();
return x++; // number
}
}
function foo3(x) {
if (typeof x === "string") {
return x.length; // string
}
else {
(function () {
x = 10;
})();
return x++; // number
}
}

95
tests/baselines/reference/typeGuardsDefeat.types Normal file
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=== tests/cases/conformance/expressions/typeGuards/typeGuardsDefeat.ts ===
// Also note that it is possible to defeat a type guard by calling a function that changes the
// type of the guarded variable.
function foo(x: number | string) {
>foo : (x: string | number) => number
>x : string | number
function f() {
>f : () => void
x = 10;
>x = 10 : number
>x : string | number
}
if (typeof x === "string") {
>typeof x === "string" : boolean
>typeof x : string
>x : string | number
f();
>f() : void
>f : () => void
return x.length; // string
>x.length : number
>x : string
>length : number
}
else {
return x++; // number
>x++ : number
>x : number
}
}
function foo2(x: number | string) {
>foo2 : (x: string | number) => number
>x : string | number
if (typeof x === "string") {
>typeof x === "string" : boolean
>typeof x : string
>x : string | number
return x.length; // string
>x.length : number
>x : string
>length : number
}
else {
(function f() {
>(function f() { x = 10; })() : void
>(function f() { x = 10; }) : () => void
>function f() { x = 10; } : () => void
>f : () => void
x = 10;
>x = 10 : number
>x : string | number
})();
return x++; // number
>x++ : number
>x : number
}
}
function foo3(x: number | string) {
>foo3 : (x: string | number) => number
>x : string | number
if (typeof x === "string") {
>typeof x === "string" : boolean
>typeof x : string
>x : string | number
return x.length; // string
>x.length : number
>x : string
>length : number
}
else {
(() => {
>(() => { x = 10; })() : void
>(() => { x = 10; }) : () => void
>() => { x = 10; } : () => void
x = 10;
>x = 10 : number
>x : string | number
})();
return x++; // number
>x++ : number
>x : number
}
}

36
tests/cases/conformance/expressions/typeGuards/typeGuardsDefeat.ts Normal file
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// Also note that it is possible to defeat a type guard by calling a function that changes the
// type of the guarded variable.
function foo(x: number | string) {
function f() {
x = 10;
}
if (typeof x === "string") {
f();
return x.length; // string
}
else {
return x++; // number
}
}
function foo2(x: number | string) {
if (typeof x === "string") {
return x.length; // string
}
else {
(function f() {
x = 10;
})();
return x++; // number
}
}
function foo3(x: number | string) {
if (typeof x === "string") {
return x.length; // string
}
else {
(() => {
x = 10;
})();
return x++; // number
}
}