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//// [typeGuardsWithInstanceOf.ts]
interface I { global: string; }
var result!: I;
var result2!: I;
if (!(result instanceof RegExp)) {
result = result2;
} else if (!result.global) {
}
// Repro from #31155
interface OnChanges {
onChanges(changes: Record<string, unknown>): void
}
interface Validator {
validate(): null | Record<string, unknown>;
}
class C {
validate() {
return {}
}
}
function foo() {
let v: Validator & Partial<OnChanges> = null as any;
if (v instanceof C) {
v // Validator & Partial<OnChanges> & C
}
v // Validator & Partial<OnChanges> via subtype reduction
// In 4.1, we introduced a change which _fixed_ a bug with CFA
// correctly setting this to be the right object. With 4.2,
// we reverted that fix in #42231 which brought behavior back to
// before 4.1.
if (v.onChanges) {
v.onChanges({});
}
}
//// [typeGuardsWithInstanceOf.js]
var result;
var result2;
if (!(result instanceof RegExp)) {
result = result2;
}
else if (!result.global) {
}
var C = /** @class */ (function () {
function C() {
}
C.prototype.validate = function () {
return {};
};
return C;
}());
function foo() {
var v = null;
if (v instanceof C) {
v; // Validator & Partial<OnChanges> & C
}
v; // Validator & Partial<OnChanges> via subtype reduction
// In 4.1, we introduced a change which _fixed_ a bug with CFA
// correctly setting this to be the right object. With 4.2,
// we reverted that fix in #42231 which brought behavior back to
// before 4.1.
if (v.onChanges) {
v.onChanges({});
}
}
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