Don't treat an instantiation expression as an assertion in skipOuterE…

…xpressions (#59538)

src/compiler/factory/nodeFactory.ts

@@ -6553,6 +6553,8 @@ export function createNodeFactory(flags: NodeFactoryFlags, baseFactory: BaseNode
                 return updateSatisfiesExpression(outerExpression, expression, outerExpression.type);
             case SyntaxKind.NonNullExpression:
                 return updateNonNullExpression(outerExpression, expression);
+            case SyntaxKind.ExpressionWithTypeArguments:
+                return updateExpressionWithTypeArguments(outerExpression, expression, outerExpression.typeArguments);
             case SyntaxKind.PartiallyEmittedExpression:
                 return updatePartiallyEmittedExpression(outerExpression, expression);
         }

src/compiler/factory/utilities.ts

@@ -630,9 +630,10 @@ export function isOuterExpression(node: Node, kinds = OuterExpressionKinds.All):
             return (kinds & OuterExpressionKinds.Parentheses) !== 0;
         case SyntaxKind.TypeAssertionExpression:
         case SyntaxKind.AsExpression:
-        case SyntaxKind.ExpressionWithTypeArguments:
         case SyntaxKind.SatisfiesExpression:
             return (kinds & OuterExpressionKinds.TypeAssertions) !== 0;
+        case SyntaxKind.ExpressionWithTypeArguments:
+            return (kinds & OuterExpressionKinds.ExpressionsWithTypeArguments) !== 0;
         case SyntaxKind.NonNullExpression:
             return (kinds & OuterExpressionKinds.NonNullAssertions) !== 0;
         case SyntaxKind.PartiallyEmittedExpression:

src/compiler/transformers/ts.ts

@@ -1689,7 +1689,7 @@ export function transformTypeScript(context: TransformationContext) {
     }
 
     function visitParenthesizedExpression(node: ParenthesizedExpression): Expression {
-        const innerExpression = skipOuterExpressions(node.expression, ~OuterExpressionKinds.Assertions);
+        const innerExpression = skipOuterExpressions(node.expression, ~(OuterExpressionKinds.Assertions | OuterExpressionKinds.ExpressionsWithTypeArguments));
         if (isAssertionExpression(innerExpression) || isSatisfiesExpression(innerExpression)) {
             // Make sure we consider all nested cast expressions, e.g.:
             // (<any><number><any>-A).x;

src/compiler/types.ts

@@ -8476,11 +8476,12 @@ export const enum OuterExpressionKinds {
     TypeAssertions = 1 << 1,
     NonNullAssertions = 1 << 2,
     PartiallyEmittedExpressions = 1 << 3,
+    ExpressionsWithTypeArguments = 1 << 4,
 
     Assertions = TypeAssertions | NonNullAssertions,
-    All = Parentheses | Assertions | PartiallyEmittedExpressions,
+    All = Parentheses | Assertions | PartiallyEmittedExpressions | ExpressionsWithTypeArguments,
 
-    ExcludeJSDocTypeAssertion = 1 << 4,
+    ExcludeJSDocTypeAssertion = 1 << 31,
 }
 
 /** @internal */
@@ -8490,6 +8491,7 @@ export type OuterExpression =
     | SatisfiesExpression
     | AsExpression
     | NonNullExpression
+    | ExpressionWithTypeArguments
     | PartiallyEmittedExpression;
 
 /** @internal */

tests/baselines/reference/api/typescript.d.ts

@@ -7346,9 +7346,10 @@ declare namespace ts {
         TypeAssertions = 2,
         NonNullAssertions = 4,
         PartiallyEmittedExpressions = 8,
+        ExpressionsWithTypeArguments = 16,
         Assertions = 6,
-        All = 15,
-        ExcludeJSDocTypeAssertion = 16,
+        All = 31,
+        ExcludeJSDocTypeAssertion = -2147483648,
     }
     type ImmediatelyInvokedFunctionExpression = CallExpression & {
         readonly expression: FunctionExpression;

tests/baselines/reference/assignmentToInstantiationExpression.errors.txt

@@ -0,0 +1,26 @@
+assignmentToInstantiationExpression.ts(2,1): error TS2364: The left-hand side of an assignment expression must be a variable or a property access.
+assignmentToInstantiationExpression.ts(6,1): error TS2454: Variable 'getValue' is used before being assigned.
+assignmentToInstantiationExpression.ts(6,1): error TS2364: The left-hand side of an assignment expression must be a variable or a property access.
+assignmentToInstantiationExpression.ts(10,1): error TS2364: The left-hand side of an assignment expression must be a variable or a property access.
+
+
+==== assignmentToInstantiationExpression.ts (4 errors) ====
+    let obj: { fn?: <T>() => T } = {};
+    obj.fn<number> = () => 1234;
+    ~~~~~~~~~~~~~~
+!!! error TS2364: The left-hand side of an assignment expression must be a variable or a property access.
+
+
+    let getValue: <T>() => T;
+    getValue<number> = () => 1234;
+    ~~~~~~~~
+!!! error TS2454: Variable 'getValue' is used before being assigned.
+    ~~~~~~~~~~~~~~~~
+!!! error TS2364: The left-hand side of an assignment expression must be a variable or a property access.
+
+
+    let getValue2!: <T>() => T;
+    getValue2<number> = () => 1234;
+    ~~~~~~~~~~~~~~~~~
+!!! error TS2364: The left-hand side of an assignment expression must be a variable or a property access.
+

tests/baselines/reference/assignmentToInstantiationExpression.js

@@ -0,0 +1,23 @@
+//// [tests/cases/compiler/assignmentToInstantiationExpression.ts] ////
+
+//// [assignmentToInstantiationExpression.ts]
+let obj: { fn?: <T>() => T } = {};
+obj.fn<number> = () => 1234;
+
+
+let getValue: <T>() => T;
+getValue<number> = () => 1234;
+
+
+let getValue2!: <T>() => T;
+getValue2<number> = () => 1234;
+
+
+//// [assignmentToInstantiationExpression.js]
+"use strict";
+var obj = {};
+(obj.fn) = function () { return 1234; };
+var getValue;
+(getValue) = function () { return 1234; };
+var getValue2;
+(getValue2) = function () { return 1234; };

tests/baselines/reference/assignmentToInstantiationExpression.symbols

@@ -0,0 +1,32 @@
+//// [tests/cases/compiler/assignmentToInstantiationExpression.ts] ////
+
+=== assignmentToInstantiationExpression.ts ===
+let obj: { fn?: <T>() => T } = {};
+>obj : Symbol(obj, Decl(assignmentToInstantiationExpression.ts, 0, 3))
+>fn : Symbol(fn, Decl(assignmentToInstantiationExpression.ts, 0, 10))
+>T : Symbol(T, Decl(assignmentToInstantiationExpression.ts, 0, 17))
+>T : Symbol(T, Decl(assignmentToInstantiationExpression.ts, 0, 17))
+
+obj.fn<number> = () => 1234;
+>obj.fn : Symbol(fn, Decl(assignmentToInstantiationExpression.ts, 0, 10))
+>obj : Symbol(obj, Decl(assignmentToInstantiationExpression.ts, 0, 3))
+>fn : Symbol(fn, Decl(assignmentToInstantiationExpression.ts, 0, 10))
+
+
+let getValue: <T>() => T;
+>getValue : Symbol(getValue, Decl(assignmentToInstantiationExpression.ts, 4, 3))
+>T : Symbol(T, Decl(assignmentToInstantiationExpression.ts, 4, 15))
+>T : Symbol(T, Decl(assignmentToInstantiationExpression.ts, 4, 15))
+
+getValue<number> = () => 1234;
+>getValue : Symbol(getValue, Decl(assignmentToInstantiationExpression.ts, 4, 3))
+
+
+let getValue2!: <T>() => T;
+>getValue2 : Symbol(getValue2, Decl(assignmentToInstantiationExpression.ts, 8, 3))
+>T : Symbol(T, Decl(assignmentToInstantiationExpression.ts, 8, 17))
+>T : Symbol(T, Decl(assignmentToInstantiationExpression.ts, 8, 17))
+
+getValue2<number> = () => 1234;
+>getValue2 : Symbol(getValue2, Decl(assignmentToInstantiationExpression.ts, 8, 3))
+

tests/baselines/reference/assignmentToInstantiationExpression.types

@@ -0,0 +1,61 @@
+//// [tests/cases/compiler/assignmentToInstantiationExpression.ts] ////
+
+=== assignmentToInstantiationExpression.ts ===
+let obj: { fn?: <T>() => T } = {};
+>obj : { fn?: <T>() => T; }
+>    : ^^^^^^^          ^^^
+>fn : (<T>() => T) | undefined
+>   : ^^ ^^^^^^^ ^^^^^^^^^^^^^
+>{} : {}
+>   : ^^
+
+obj.fn<number> = () => 1234;
+>obj.fn<number> = () => 1234 : () => number
+>                            : ^^^^^^^^^^^^
+>obj.fn<number> : (() => number) | undefined
+>               : ^^^^^^^^^^^^^^^^^^^^^^^^^^
+>obj.fn : (<T>() => T) | undefined
+>       : ^^ ^^^^^^^ ^^^^^^^^^^^^^
+>obj : { fn?: <T>() => T; }
+>    : ^^^^^^^          ^^^
+>fn : (<T>() => T) | undefined
+>   : ^^ ^^^^^^^ ^^^^^^^^^^^^^
+>() => 1234 : () => number
+>           : ^^^^^^^^^^^^
+>1234 : 1234
+>     : ^^^^
+
+
+let getValue: <T>() => T;
+>getValue : <T>() => T
+>         : ^ ^^^^^^^ 
+
+getValue<number> = () => 1234;
+>getValue<number> = () => 1234 : () => number
+>                              : ^^^^^^^^^^^^
+>getValue<number> : () => number
+>                 : ^^^^^^^^^^^^
+>getValue : <T>() => T
+>         : ^ ^^^^^^^ 
+>() => 1234 : () => number
+>           : ^^^^^^^^^^^^
+>1234 : 1234
+>     : ^^^^
+
+
+let getValue2!: <T>() => T;
+>getValue2 : <T>() => T
+>          : ^ ^^^^^^^ 
+
+getValue2<number> = () => 1234;
+>getValue2<number> = () => 1234 : () => number
+>                               : ^^^^^^^^^^^^
+>getValue2<number> : () => number
+>                  : ^^^^^^^^^^^^
+>getValue2 : <T>() => T
+>          : ^ ^^^^^^^ 
+>() => 1234 : () => number
+>           : ^^^^^^^^^^^^
+>1234 : 1234
+>     : ^^^^
+

tests/cases/compiler/assignmentToInstantiationExpression.ts

@@ -0,0 +1,12 @@
+// @strict: true
+
+let obj: { fn?: <T>() => T } = {};
+obj.fn<number> = () => 1234;
+
+
+let getValue: <T>() => T;
+getValue<number> = () => 1234;
+
+
+let getValue2!: <T>() => T;
+getValue2<number> = () => 1234;