fix #518

Author: DonJayamanne

src/client/debugger/DebugClients/LocalDebugClient.ts

@@ -66,7 +66,7 @@ export class LocalDebugClient extends DebugClient {
     }
     public LaunchApplicationToDebug(dbgServer: IDebugServer, processErrored: (error: any) => void): Promise<any> {
         return new Promise<any>((resolve, reject) => {
-            let fileDir = path.dirname(this.args.program);
+            let fileDir = this.args && this.args.program ? path.dirname(this.args.program) : '';
             let processCwd = fileDir;
             if (typeof this.args.cwd === 'string' && this.args.cwd.length > 0 && this.args.cwd !== 'null') {
                 processCwd = this.args.cwd;

src/client/debugger/Main.ts

@@ -81,7 +81,10 @@ export class PythonDebugger extends DebugSession {
     private debugServer: BaseDebugServer;
 
     private startDebugServer(): Promise<IDebugServer> {
-        let programDirectory = this.launchArgs ? path.dirname(this.launchArgs.program) : this.attachArgs.localRoot;
+        let programDirectory = '';
+        if ((this.launchArgs && this.launchArgs.program) || (this.attachArgs && this.attachArgs.localRoot)) {
+            programDirectory = this.launchArgs ? path.dirname(this.launchArgs.program) : this.attachArgs.localRoot;
+        }
         if (this.launchArgs && typeof this.launchArgs.cwd === 'string' && this.launchArgs.cwd.length > 0 && this.launchArgs.cwd !== 'null') {
             programDirectory = this.launchArgs.cwd;
         }