59 lines
849 B
TypeScript
59 lines
849 B
TypeScript
// @strict: true
|
|
|
|
// Repro from #8383
|
|
|
|
class A {
|
|
prop!: { a: string; };
|
|
}
|
|
|
|
class B {
|
|
prop!: { b: string; }
|
|
}
|
|
|
|
function isA(x: any): x is A {
|
|
return x instanceof A;
|
|
}
|
|
|
|
function isB(x: any): x is B {
|
|
return x instanceof B;
|
|
}
|
|
|
|
function f1(x: A | B) {
|
|
while (true) {
|
|
if (x instanceof A) {
|
|
x.prop.a;
|
|
}
|
|
else if (x instanceof B) {
|
|
x.prop.b;
|
|
}
|
|
}
|
|
}
|
|
|
|
function f2(x: A | B) {
|
|
while (true) {
|
|
if (isA(x)) {
|
|
x.prop.a;
|
|
}
|
|
else if (isB(x)) {
|
|
x.prop.b;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Repro from #28100
|
|
|
|
class Foo1
|
|
{
|
|
x: number; // Error
|
|
constructor() {
|
|
if (this instanceof Boolean) {
|
|
}
|
|
}
|
|
}
|
|
|
|
class Foo2
|
|
{
|
|
x: number; // Error
|
|
constructor() {
|
|
}
|
|
}
|