Add regression test

Author: ahejlsberg

tests/baselines/reference/nonPrimitiveAndEmptyObject.js

@@ -0,0 +1,32 @@
+//// [nonPrimitiveAndEmptyObject.ts]
+// Repro from #49480
+
+export interface BarProps {
+    barProp?: string;
+}
+
+export interface FooProps {
+    fooProps?: BarProps & object;
+}
+
+declare const foo: FooProps;
+const { fooProps = {} } = foo;
+
+fooProps.barProp;
+
+
+//// [nonPrimitiveAndEmptyObject.js]
+"use strict";
+// Repro from #49480
+exports.__esModule = true;
+var _a = foo.fooProps, fooProps = _a === void 0 ? {} : _a;
+fooProps.barProp;
+
+
+//// [nonPrimitiveAndEmptyObject.d.ts]
+export interface BarProps {
+    barProp?: string;
+}
+export interface FooProps {
+    fooProps?: BarProps & object;
+}

tests/baselines/reference/nonPrimitiveAndEmptyObject.symbols

@@ -0,0 +1,31 @@
+=== tests/cases/conformance/types/nonPrimitive/nonPrimitiveAndEmptyObject.ts ===
+// Repro from #49480
+
+export interface BarProps {
+>BarProps : Symbol(BarProps, Decl(nonPrimitiveAndEmptyObject.ts, 0, 0))
+
+    barProp?: string;
+>barProp : Symbol(BarProps.barProp, Decl(nonPrimitiveAndEmptyObject.ts, 2, 27))
+}
+
+export interface FooProps {
+>FooProps : Symbol(FooProps, Decl(nonPrimitiveAndEmptyObject.ts, 4, 1))
+
+    fooProps?: BarProps & object;
+>fooProps : Symbol(FooProps.fooProps, Decl(nonPrimitiveAndEmptyObject.ts, 6, 27))
+>BarProps : Symbol(BarProps, Decl(nonPrimitiveAndEmptyObject.ts, 0, 0))
+}
+
+declare const foo: FooProps;
+>foo : Symbol(foo, Decl(nonPrimitiveAndEmptyObject.ts, 10, 13))
+>FooProps : Symbol(FooProps, Decl(nonPrimitiveAndEmptyObject.ts, 4, 1))
+
+const { fooProps = {} } = foo;
+>fooProps : Symbol(fooProps, Decl(nonPrimitiveAndEmptyObject.ts, 11, 7))
+>foo : Symbol(foo, Decl(nonPrimitiveAndEmptyObject.ts, 10, 13))
+
+fooProps.barProp;
+>fooProps.barProp : Symbol(BarProps.barProp, Decl(nonPrimitiveAndEmptyObject.ts, 2, 27))
+>fooProps : Symbol(fooProps, Decl(nonPrimitiveAndEmptyObject.ts, 11, 7))
+>barProp : Symbol(BarProps.barProp, Decl(nonPrimitiveAndEmptyObject.ts, 2, 27))
+

tests/baselines/reference/nonPrimitiveAndEmptyObject.types

@@ -0,0 +1,26 @@
+=== tests/cases/conformance/types/nonPrimitive/nonPrimitiveAndEmptyObject.ts ===
+// Repro from #49480
+
+export interface BarProps {
+    barProp?: string;
+>barProp : string | undefined
+}
+
+export interface FooProps {
+    fooProps?: BarProps & object;
+>fooProps : (BarProps & object) | undefined
+}
+
+declare const foo: FooProps;
+>foo : FooProps
+
+const { fooProps = {} } = foo;
+>fooProps : BarProps & object
+>{} : {}
+>foo : FooProps
+
+fooProps.barProp;
+>fooProps.barProp : string | undefined
+>fooProps : BarProps & object
+>barProp : string | undefined
+

tests/cases/conformance/types/nonPrimitive/nonPrimitiveAndEmptyObject.ts

@@ -0,0 +1,17 @@
+// @strict: true
+// @declaration: true
+
+// Repro from #49480
+
+export interface BarProps {
+    barProp?: string;
+}
+
+export interface FooProps {
+    fooProps?: BarProps & object;
+}
+
+declare const foo: FooProps;
+const { fooProps = {} } = foo;
+
+fooProps.barProp;