Cherry-pick PR #42766 into release-4.2 (#42950)

Component commits:
ed26816 Avoid getting undefined `callSignatures`/`constructSignatures` in `getPropertyOfType`
e350c35 (#40228) introduced a subtle bug: it switched the flags to an
alias, dropping `SymbolFlags.Property` --- and that makes
`symbolIsValue()` get to the `resolveAlias(symbol)` call, which leads to
`getPropertyOfType()` with`resolved.callSignatures`+`constructSignatures`
being `undefined`.  So initialize them in `setStructuredTypeMembers`
before calling `getNamedMembers()`.

Fixes #42350

Co-authored-by: Eli Barzilay <eli@barzilay.org>

Author: TypeScript Bot

src/compiler/checker.ts

@@ -3846,13 +3846,16 @@ namespace ts {
         }
 
         function setStructuredTypeMembers(type: StructuredType, members: SymbolTable, callSignatures: readonly Signature[], constructSignatures: readonly Signature[], stringIndexInfo: IndexInfo | undefined, numberIndexInfo: IndexInfo | undefined): ResolvedType {
-            (<ResolvedType>type).members = members;
-            (<ResolvedType>type).properties = members === emptySymbols ? emptyArray : getNamedMembers(members);
-            (<ResolvedType>type).callSignatures = callSignatures;
-            (<ResolvedType>type).constructSignatures = constructSignatures;
-            (<ResolvedType>type).stringIndexInfo = stringIndexInfo;
-            (<ResolvedType>type).numberIndexInfo = numberIndexInfo;
-            return <ResolvedType>type;
+            const resolved = <ResolvedType>type;
+            resolved.members = members;
+            resolved.properties = emptyArray;
+            resolved.callSignatures = callSignatures;
+            resolved.constructSignatures = constructSignatures;
+            resolved.stringIndexInfo = stringIndexInfo;
+            resolved.numberIndexInfo = numberIndexInfo;
+            // This can loop back to getPropertyOfType() which would crash if `callSignatures` & `constructSignatures` are not initialized.
+            if (members !== emptySymbols) resolved.properties = getNamedMembers(members);
+            return resolved;
         }
 
         function createAnonymousType(symbol: Symbol | undefined, members: SymbolTable, callSignatures: readonly Signature[], constructSignatures: readonly Signature[], stringIndexInfo: IndexInfo | undefined, numberIndexInfo: IndexInfo | undefined): ResolvedType {

tests/baselines/reference/moduleExportsAliasLoop1.errors.txt

@@ -0,0 +1,9 @@
+tests/cases/conformance/salsa/x.js(1,9): error TS2339: Property 'fn1' does not exist on type 'typeof import("tests/cases/conformance/salsa/x")'.
+
+
+==== tests/cases/conformance/salsa/x.js (1 errors) ====
+    exports.fn1();
+            ~~~
+!!! error TS2339: Property 'fn1' does not exist on type 'typeof import("tests/cases/conformance/salsa/x")'.
+    exports.fn2 = Math.min;
+    

tests/baselines/reference/moduleExportsAliasLoop1.symbols

@@ -0,0 +1,12 @@
+=== tests/cases/conformance/salsa/x.js ===
+exports.fn1();
+>exports : Symbol("tests/cases/conformance/salsa/x", Decl(x.js, 0, 0))
+
+exports.fn2 = Math.min;
+>exports.fn2 : Symbol(fn2, Decl(x.js, 0, 14))
+>exports : Symbol(fn2, Decl(x.js, 0, 14))
+>fn2 : Symbol(fn2, Decl(x.js, 0, 14))
+>Math.min : Symbol(fn2, Decl(lib.es5.d.ts, --, --))
+>Math : Symbol(Math, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
+>min : Symbol(fn2, Decl(lib.es5.d.ts, --, --))
+

tests/baselines/reference/moduleExportsAliasLoop1.types

@@ -0,0 +1,16 @@
+=== tests/cases/conformance/salsa/x.js ===
+exports.fn1();
+>exports.fn1() : any
+>exports.fn1 : any
+>exports : typeof import("tests/cases/conformance/salsa/x")
+>fn1 : any
+
+exports.fn2 = Math.min;
+>exports.fn2 = Math.min : (...values: number[]) => number
+>exports.fn2 : (...values: number[]) => number
+>exports : typeof import("tests/cases/conformance/salsa/x")
+>fn2 : (...values: number[]) => number
+>Math.min : (...values: number[]) => number
+>Math : Math
+>min : (...values: number[]) => number
+

tests/baselines/reference/moduleExportsAliasLoop2.errors.txt

@@ -0,0 +1,10 @@
+tests/cases/conformance/salsa/x.js(2,9): error TS2339: Property 'fn1' does not exist on type 'typeof import("tests/cases/conformance/salsa/x")'.
+
+
+==== tests/cases/conformance/salsa/x.js (1 errors) ====
+    const Foo = { min: 3 };
+    exports.fn1();
+            ~~~
+!!! error TS2339: Property 'fn1' does not exist on type 'typeof import("tests/cases/conformance/salsa/x")'.
+    exports.fn2 = Foo.min;
+    

tests/baselines/reference/moduleExportsAliasLoop2.symbols

@@ -0,0 +1,16 @@
+=== tests/cases/conformance/salsa/x.js ===
+const Foo = { min: 3 };
+>Foo : Symbol(Foo, Decl(x.js, 0, 5))
+>min : Symbol(min, Decl(x.js, 0, 13))
+
+exports.fn1();
+>exports : Symbol("tests/cases/conformance/salsa/x", Decl(x.js, 0, 0))
+
+exports.fn2 = Foo.min;
+>exports.fn2 : Symbol(fn2, Decl(x.js, 1, 14))
+>exports : Symbol(fn2, Decl(x.js, 1, 14))
+>fn2 : Symbol(fn2, Decl(x.js, 1, 14))
+>Foo.min : Symbol(fn2, Decl(x.js, 0, 13))
+>Foo : Symbol(Foo, Decl(x.js, 0, 5))
+>min : Symbol(fn2, Decl(x.js, 0, 13))
+

tests/baselines/reference/moduleExportsAliasLoop2.types

@@ -0,0 +1,22 @@
+=== tests/cases/conformance/salsa/x.js ===
+const Foo = { min: 3 };
+>Foo : { min: number; }
+>{ min: 3 } : { min: number; }
+>min : number
+>3 : 3
+
+exports.fn1();
+>exports.fn1() : any
+>exports.fn1 : any
+>exports : typeof import("tests/cases/conformance/salsa/x")
+>fn1 : any
+
+exports.fn2 = Foo.min;
+>exports.fn2 = Foo.min : number
+>exports.fn2 : number
+>exports : typeof import("tests/cases/conformance/salsa/x")
+>fn2 : number
+>Foo.min : number
+>Foo : { min: number; }
+>min : number
+

tests/cases/conformance/salsa/moduleExportsAliasLoop1.ts

@@ -0,0 +1,6 @@
+// @noEmit: true
+// @allowJs: true
+// @checkJs: true
+// @filename: x.js
+exports.fn1();
+exports.fn2 = Math.min;

tests/cases/conformance/salsa/moduleExportsAliasLoop2.ts

@@ -0,0 +1,7 @@
+// @noEmit: true
+// @allowJs: true
+// @checkJs: true
+// @filename: x.js
+const Foo = { min: 3 };
+exports.fn1();
+exports.fn2 = Foo.min;