Removed unnecessary use-before-define error for const enums (#53625)

Author: JoshuaKGoldberg

src/compiler/checker.ts

@@ -3797,12 +3797,6 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
             else if (result.flags & SymbolFlags.RegularEnum) {
                 diagnosticMessage = error(errorLocation, Diagnostics.Enum_0_used_before_its_declaration, declarationName);
             }
-            else {
-                Debug.assert(!!(result.flags & SymbolFlags.ConstEnum));
-                if (shouldPreserveConstEnums(compilerOptions)) {
-                    diagnosticMessage = error(errorLocation, Diagnostics.Enum_0_used_before_its_declaration, declarationName);
-                }
-            }
 
             if (diagnosticMessage) {
                 addRelatedInfo(diagnosticMessage,

tests/baselines/reference/blockScopedEnumVariablesUseBeforeDef_preserve.errors.txt

@@ -1,8 +1,7 @@
 tests/cases/compiler/blockScopedEnumVariablesUseBeforeDef_preserve.ts(2,12): error TS2450: Enum 'E' used before its declaration.
-tests/cases/compiler/blockScopedEnumVariablesUseBeforeDef_preserve.ts(7,12): error TS2450: Enum 'E' used before its declaration.
 
 
-==== tests/cases/compiler/blockScopedEnumVariablesUseBeforeDef_preserve.ts (2 errors) ====
+==== tests/cases/compiler/blockScopedEnumVariablesUseBeforeDef_preserve.ts (1 errors) ====
     function foo1() {
         return E.A
                ~
@@ -13,8 +12,14 @@ tests/cases/compiler/blockScopedEnumVariablesUseBeforeDef_preserve.ts(7,12): err
 
     function foo2() {
         return E.A
-               ~
-!!! error TS2450: Enum 'E' used before its declaration.
-!!! related TS2728 tests/cases/compiler/blockScopedEnumVariablesUseBeforeDef_preserve.ts:8:16: 'E' is declared here.
         const enum E { A }
-    }
+    }
+    
+    const config = {
+        a: AfterObject.A,
+    };
+    
+    const enum AfterObject {
+        A = 2,
+    }
+    

tests/baselines/reference/blockScopedEnumVariablesUseBeforeDef_preserve.js

@@ -7,7 +7,16 @@ function foo1() {
 function foo2() {
     return E.A
     const enum E { A }
-}
+}
+
+const config = {
+    a: AfterObject.A,
+};
+
+const enum AfterObject {
+    A = 2,
+}
+
 
 //// [blockScopedEnumVariablesUseBeforeDef_preserve.js]
 function foo1() {
@@ -24,3 +33,10 @@ function foo2() {
         E[E["A"] = 0] = "A";
     })(E || (E = {}));
 }
+var config = {
+    a: 2 /* AfterObject.A */,
+};
+var AfterObject;
+(function (AfterObject) {
+    AfterObject[AfterObject["A"] = 2] = "A";
+})(AfterObject || (AfterObject = {}));

tests/baselines/reference/blockScopedEnumVariablesUseBeforeDef_preserve.symbols

@@ -24,3 +24,22 @@ function foo2() {
 >E : Symbol(E, Decl(blockScopedEnumVariablesUseBeforeDef_preserve.ts, 6, 14))
 >A : Symbol(E.A, Decl(blockScopedEnumVariablesUseBeforeDef_preserve.ts, 7, 18))
 }
+
+const config = {
+>config : Symbol(config, Decl(blockScopedEnumVariablesUseBeforeDef_preserve.ts, 10, 5))
+
+    a: AfterObject.A,
+>a : Symbol(a, Decl(blockScopedEnumVariablesUseBeforeDef_preserve.ts, 10, 16))
+>AfterObject.A : Symbol(AfterObject.A, Decl(blockScopedEnumVariablesUseBeforeDef_preserve.ts, 14, 24))
+>AfterObject : Symbol(AfterObject, Decl(blockScopedEnumVariablesUseBeforeDef_preserve.ts, 12, 2))
+>A : Symbol(AfterObject.A, Decl(blockScopedEnumVariablesUseBeforeDef_preserve.ts, 14, 24))
+
+};
+
+const enum AfterObject {
+>AfterObject : Symbol(AfterObject, Decl(blockScopedEnumVariablesUseBeforeDef_preserve.ts, 12, 2))
+
+    A = 2,
+>A : Symbol(AfterObject.A, Decl(blockScopedEnumVariablesUseBeforeDef_preserve.ts, 14, 24))
+}
+

tests/baselines/reference/blockScopedEnumVariablesUseBeforeDef_preserve.types

@@ -24,3 +24,24 @@ function foo2() {
 >E : E
 >A : E.A
 }
+
+const config = {
+>config : { a: AfterObject; }
+>{    a: AfterObject.A,} : { a: AfterObject; }
+
+    a: AfterObject.A,
+>a : AfterObject
+>AfterObject.A : AfterObject
+>AfterObject : typeof AfterObject
+>A : AfterObject
+
+};
+
+const enum AfterObject {
+>AfterObject : AfterObject
+
+    A = 2,
+>A : AfterObject.A
+>2 : 2
+}
+

tests/cases/compiler/blockScopedEnumVariablesUseBeforeDef_preserve.ts

@@ -9,4 +9,12 @@ function foo1() {
 function foo2() {
     return E.A
     const enum E { A }
-}
+}
+
+const config = {
+    a: AfterObject.A,
+};
+
+const enum AfterObject {
+    A = 2,
+}