Fix declaration emit crash (#58872)

src/compiler/checker.ts

@@ -541,6 +541,7 @@ import {
     isExternalModuleIndicator,
     isExternalModuleNameRelative,
     isExternalModuleReference,
+    isExternalModuleSymbol,
     isExternalOrCommonJsModule,
     isForInOrOfStatement,
     isForInStatement,
@@ -9002,7 +9003,7 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                         const parentSymbol = nodeSymbol
                             && isSymbolAccessible(nodeSymbol, context.enclosingDeclaration, meaning, /*shouldComputeAliasesToMakeVisible*/ false).accessibility === SymbolAccessibility.Accessible
                             && lookupSymbolChain(nodeSymbol, context, meaning, /*yieldModuleSymbol*/ true)[0];
-                        if (parentSymbol && parentSymbol.flags & SymbolFlags.Module) {
+                        if (parentSymbol && isExternalModuleSymbol(parentSymbol)) {
                             name = getSpecifierForModuleSymbol(parentSymbol, context);
                         }
                         else {

src/compiler/utilities.ts

@@ -633,6 +633,15 @@ export function isTransientSymbol(symbol: Symbol): symbol is TransientSymbol {
     return (symbol.flags & SymbolFlags.Transient) !== 0;
 }
 
+/**
+ * True if the symbol is for an external module, as opposed to a namespace.
+ *
+ * @internal
+ */
+export function isExternalModuleSymbol(moduleSymbol: Symbol): boolean {
+    return !!(moduleSymbol.flags & SymbolFlags.Module) && (moduleSymbol.escapedName as string).charCodeAt(0) === CharacterCodes.doubleQuote;
+}
+
 const stringWriter = createSingleLineStringWriter();
 
 function createSingleLineStringWriter(): EmitTextWriter {

src/services/utilities.ts

@@ -2408,15 +2408,6 @@ export function isTypeKeywordTokenOrIdentifier(node: Node) {
     return isTypeKeywordToken(node) || isIdentifier(node) && node.text === "type";
 }
 
-/**
- * True if the symbol is for an external module, as opposed to a namespace.
- *
- * @internal
- */
-export function isExternalModuleSymbol(moduleSymbol: Symbol): boolean {
-    return !!(moduleSymbol.flags & SymbolFlags.Module) && moduleSymbol.name.charCodeAt(0) === CharacterCodes.doubleQuote;
-}
-
 /**
  * Returns `true` the first time it encounters a node and `false` afterwards.
  *