Fix module loading error

(commandLineOptions_stringToEnum would be undefined if optionDeclarations wasn't loaded yet)

Author: Andy Hanson

src/services/services.ts

@@ -1920,12 +1920,16 @@ namespace ts {
         sourceMapText?: string;
     }
 
-    const commandLineOptions_stringToEnum = <CommandLineOptionOfCustomType[]>filter(optionDeclarations, o => {
-        return typeof o.type === "object" && !forEachValue(<Map<any>> o.type, v => typeof v !== "number");
-    });
+
+
+    let commandLineOptions_stringToEnum: CommandLineOptionOfCustomType[];
 
     /** JS users may pass in string values for enum compiler options (such as ModuleKind), so convert. */
-    function fixupCompilerOptions(options: CompilerOptions, diagnostics: Diagnostic[]) {
+    function fixupCompilerOptions(options: CompilerOptions, diagnostics: Diagnostic[]): CompilerOptions {
+        // Lazily create this value to fix module loading errors.
+        commandLineOptions_stringToEnum = commandLineOptions_stringToEnum || <CommandLineOptionOfCustomType[]>filter(optionDeclarations, o =>
+            typeof o.type === "object" && !forEachValue(<Map<any>> o.type, v => typeof v !== "number"));
+
         options = clone(options);
 
         for (const opt of commandLineOptions_stringToEnum) {