Fix elided var handling in declaration emit visibility checks (#58605)

Co-authored-by: TypeScript Bot <typescriptbot@microsoft.com>

src/compiler/checker.ts

@@ -5862,9 +5862,16 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
             return { accessibility: SymbolAccessibility.Accessible };
         }
 
+        if (!symbol) {
+            return {
+                accessibility: SymbolAccessibility.NotResolved,
+                errorSymbolName: getTextOfNode(firstIdentifier),
+                errorNode: firstIdentifier,
+            };
+        }
         // Verify if the symbol is accessible
-        return (symbol && hasVisibleDeclarations(symbol, shouldComputeAliasToMakeVisible)) || {
-            accessibility: SymbolAccessibility.NotResolved,
+        return hasVisibleDeclarations(symbol, shouldComputeAliasToMakeVisible) || {
+            accessibility: SymbolAccessibility.NotAccessible,
             errorSymbolName: getTextOfNode(firstIdentifier),
             errorNode: firstIdentifier,
         };

tests/baselines/reference/declarationEmitInvalidExport.errors.txt

@@ -1,11 +1,14 @@
+declarationEmitInvalidExport.ts(4,30): error TS4081: Exported type alias 'MyClass' has or is using private name 'myClass'.
 declarationEmitInvalidExport.ts(5,1): error TS1128: Declaration or statement expected.
 
 
-==== declarationEmitInvalidExport.ts (1 errors) ====
+==== declarationEmitInvalidExport.ts (2 errors) ====
     if (false) {
       export var myClass = 0;
     }
     export type MyClass = typeof myClass;
+                                 ~~~~~~~
+!!! error TS4081: Exported type alias 'MyClass' has or is using private name 'myClass'.
     }
     ~
 !!! error TS1128: Declaration or statement expected.

tests/baselines/reference/declarationEmitInvalidExport.js

@@ -14,7 +14,3 @@ Object.defineProperty(exports, "__esModule", { value: true });
 if (false) {
     exports.myClass = 0;
 }
-
-
-//// [declarationEmitInvalidExport.d.ts]
-export type MyClass = typeof myClass;

tests/baselines/reference/declarationEmitVarInElidedBlock.errors.txt

@@ -0,0 +1,10 @@
+declarationEmitVarInElidedBlock.ts(4,22): error TS4025: Exported variable 'b' has or is using private name 'a'.
+
+
+==== declarationEmitVarInElidedBlock.ts (1 errors) ====
+    {
+        var a = "";
+    }
+    export let b: typeof a;
+                         ~
+!!! error TS4025: Exported variable 'b' has or is using private name 'a'.

tests/baselines/reference/declarationEmitVarInElidedBlock.symbols

@@ -0,0 +1,11 @@
+//// [tests/cases/compiler/declarationEmitVarInElidedBlock.ts] ////
+
+=== declarationEmitVarInElidedBlock.ts ===
+{
+    var a = "";
+>a : Symbol(a, Decl(declarationEmitVarInElidedBlock.ts, 1, 7))
+}
+export let b: typeof a;
+>b : Symbol(b, Decl(declarationEmitVarInElidedBlock.ts, 3, 10))
+>a : Symbol(a, Decl(declarationEmitVarInElidedBlock.ts, 1, 7))
+

tests/baselines/reference/declarationEmitVarInElidedBlock.types

@@ -0,0 +1,16 @@
+//// [tests/cases/compiler/declarationEmitVarInElidedBlock.ts] ////
+
+=== declarationEmitVarInElidedBlock.ts ===
+{
+    var a = "";
+>a : string
+>  : ^^^^^^
+>"" : ""
+>   : ^^
+}
+export let b: typeof a;
+>b : string
+>  : ^^^^^^
+>a : string
+>  : ^^^^^^
+

tests/cases/compiler/declarationEmitVarInElidedBlock.ts

@@ -0,0 +1,6 @@
+// @declaration: true
+// @emitDeclarationOnly: true
+{
+    var a = "";
+}
+export let b: typeof a;