Add test case for const assignment via type assertion per RyanCavanaugh feedback

Co-authored-by: RyanCavanaugh <6685088+RyanCavanaugh@users.noreply.github.com>

Author: Copilot

tests/baselines/reference/usedBeforeAssignedTypeAssertion.errors.txt

@@ -1,7 +1,8 @@
-usedBeforeAssignedTypeAssertion.ts(28,12): error TS2454: Variable 'uninitialized' is used before being assigned.
+usedBeforeAssignedTypeAssertion.ts(28,6): error TS2588: Cannot assign to 'm' because it is a constant.
+usedBeforeAssignedTypeAssertion.ts(34,12): error TS2454: Variable 'uninitialized' is used before being assigned.
 
 
-==== usedBeforeAssignedTypeAssertion.ts (1 errors) ====
+==== usedBeforeAssignedTypeAssertion.ts (2 errors) ====
     // Test case for type assertion (angle bracket syntax) - assignment should not error
     function testTypeAssertion() {
         let x: number;
@@ -26,6 +27,14 @@ usedBeforeAssignedTypeAssertion.ts(28,12): error TS2454: Variable 'uninitialized
         ((nested as any) as unknown) = "test"; // Should not error
     }
 
+    // Test case for const assignment via type assertion - should error
+    function testConstAssignment() {
+        const m = 32;
+        (m as any) = 16; // Should error - cannot assign to const
+         ~
+!!! error TS2588: Cannot assign to 'm' because it is a constant.
+    }
+    
     // Test cases that should still produce errors for proper context
     function shouldStillError() {
         let uninitialized: number;

tests/baselines/reference/usedBeforeAssignedTypeAssertion.js

@@ -25,6 +25,12 @@ function testNested() {
     ((nested as any) as unknown) = "test"; // Should not error
 }
 
+// Test case for const assignment via type assertion - should error
+function testConstAssignment() {
+    const m = 32;
+    (m as any) = 16; // Should error - cannot assign to const
+}
+
 // Test cases that should still produce errors for proper context
 function shouldStillError() {
     let uninitialized: number;
@@ -53,6 +59,11 @@ function testNested() {
     var nested;
     nested = "test"; // Should not error
 }
+// Test case for const assignment via type assertion - should error
+function testConstAssignment() {
+    var m = 32;
+    m = 16; // Should error - cannot assign to const
+}
 // Test cases that should still produce errors for proper context
 function shouldStillError() {
     var uninitialized;

tests/baselines/reference/usedBeforeAssignedTypeAssertion.symbols

@@ -45,13 +45,24 @@ function testNested() {
 >nested : Symbol(nested, Decl(usedBeforeAssignedTypeAssertion.ts, 20, 7))
 }
 
+// Test case for const assignment via type assertion - should error
+function testConstAssignment() {
+>testConstAssignment : Symbol(testConstAssignment, Decl(usedBeforeAssignedTypeAssertion.ts, 22, 1))
+
+    const m = 32;
+>m : Symbol(m, Decl(usedBeforeAssignedTypeAssertion.ts, 26, 9))
+
+    (m as any) = 16; // Should error - cannot assign to const
+>m : Symbol(m, Decl(usedBeforeAssignedTypeAssertion.ts, 26, 9))
+}
+
 // Test cases that should still produce errors for proper context
 function shouldStillError() {
->shouldStillError : Symbol(shouldStillError, Decl(usedBeforeAssignedTypeAssertion.ts, 22, 1))
+>shouldStillError : Symbol(shouldStillError, Decl(usedBeforeAssignedTypeAssertion.ts, 28, 1))
 
     let uninitialized: number;
->uninitialized : Symbol(uninitialized, Decl(usedBeforeAssignedTypeAssertion.ts, 26, 7))
+>uninitialized : Symbol(uninitialized, Decl(usedBeforeAssignedTypeAssertion.ts, 32, 7))
 
     return uninitialized; // Should error - never assigned
->uninitialized : Symbol(uninitialized, Decl(usedBeforeAssignedTypeAssertion.ts, 26, 7))
+>uninitialized : Symbol(uninitialized, Decl(usedBeforeAssignedTypeAssertion.ts, 32, 7))
 }

tests/baselines/reference/usedBeforeAssignedTypeAssertion.types

@@ -91,6 +91,30 @@ function testNested() {
 >       : ^^^^^^
 }
 
+// Test case for const assignment via type assertion - should error
+function testConstAssignment() {
+>testConstAssignment : () => void
+>                    : ^^^^^^^^^^
+
+    const m = 32;
+>m : 32
+>  : ^^
+>32 : 32
+>   : ^^
+
+    (m as any) = 16; // Should error - cannot assign to const
+>(m as any) = 16 : 16
+>                : ^^
+>(m as any) : any
+>           : ^^^
+>m as any : any
+>         : ^^^
+>m : any
+>  : ^^^
+>16 : 16
+>   : ^^
+}
+
 // Test cases that should still produce errors for proper context
 function shouldStillError() {
 >shouldStillError : () => number

tests/cases/compiler/usedBeforeAssignedTypeAssertion.ts

@@ -24,6 +24,12 @@ function testNested() {
     ((nested as any) as unknown) = "test"; // Should not error
 }
 
+// Test case for const assignment via type assertion - should error
+function testConstAssignment() {
+    const m = 32;
+    (m as any) = 16; // Should error - cannot assign to const
+}
+
 // Test cases that should still produce errors for proper context
 function shouldStillError() {
     let uninitialized: number;