From 8648b4cccf337e494b4f8fc167cc28636f55de6a Mon Sep 17 00:00:00 2001
From: Hemant <133942800+hk2166@users.noreply.github.com>
Date: Tue, 18 Nov 2025 13:24:12 +0530
Subject: [PATCH] feat(compiler): improve error message when type alias is used
 as value #7990

---
 src/compiler/checker.ts                      |  5 ++++
 src/compiler/diagnosticMessages.json         |  4 +++
 tests/cases/compiler/typeAliasUsedAsValue.ts | 26 ++++++++++++++++++++
 3 files changed, 35 insertions(+)
 create mode 100644 tests/cases/compiler/typeAliasUsedAsValue.ts

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index ba5765c0826a3..b33026587b4a5 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -27656,6 +27656,11 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                     return Diagnostics.No_value_exists_in_scope_for_the_shorthand_property_0_Either_declare_one_or_provide_an_initializer;
                 }
                 else {
+                    // Check if there's a type symbol with the same name
+                    const typeSymbol = resolveName(node, node.escapedText, SymbolFlags.Type, /*nameNotFoundMessage*/ undefined, /*isUse*/ false);
+                    if (typeSymbol && !(typeSymbol.flags & SymbolFlags.Value)) {
+                        return Diagnostics.Cannot_find_name_0_1_only_refers_to_a_type_but_is_being_used_as_a_value_here;
+                    }
                     return Diagnostics.Cannot_find_name_0;
                 }
         }
diff --git a/src/compiler/diagnosticMessages.json b/src/compiler/diagnosticMessages.json
index 75da7fcff9347..3208c29bc20c2 100644
--- a/src/compiler/diagnosticMessages.json
+++ b/src/compiler/diagnosticMessages.json
@@ -2828,6 +2828,10 @@
         "category": "Error",
         "code": 2552
     },
+    "Cannot find name '{0}'. '{1}' only refers to a type, but is being used as a value here.": {
+        "category": "Error",
+        "code": 2888
+    },
     "Computed values are not permitted in an enum with string valued members.": {
         "category": "Error",
         "code": 2553
diff --git a/tests/cases/compiler/typeAliasUsedAsValue.ts b/tests/cases/compiler/typeAliasUsedAsValue.ts
new file mode 100644
index 0000000000000..70479fa55666a
--- /dev/null
+++ b/tests/cases/compiler/typeAliasUsedAsValue.ts
@@ -0,0 +1,26 @@
+// @filename: mytypes.ts
+export class MyClass {
+    public a: number;
+}
+
+export type MyClassAlias = MyClass;
+
+// @filename: main.ts
+import {MyClassAlias} from './mytypes';
+
+let a: MyClassAlias = new MyClassAlias(); // Error: should show better message
+let b = MyClassAlias; // Error: should show better message
+
+// Test with local type alias
+type LocalAlias = string;
+let c = LocalAlias; // Error: should show better message
+
+// Test with interface
+interface MyInterface {
+    prop: string;
+}
+let d = MyInterface; // Error: should show better message
+
+// Test with generic type alias
+type GenericAlias<T> = T[];
+let e = GenericAlias; // Error: should show better message