fix cpp task labels and ensure they can be run

This pull request fixes the following problems:
- cpp task labels are displayed as "undefined: xxxx" and it is wrong
- Theia always fails to run tasks defined in cpp extension. When they are started from the "Run Task", users either get "launch config not found" error, or an exception that says "Error attaching to terminal".

fixed #6204

packages/cpp/src/browser/cpp-task-provider.spec.ts

@@ -99,7 +99,7 @@ describe('CppTaskProvider', function (): void {
 
         const resolvedTask = await taskProvider.resolveTask(tasks[0]);
         expect(resolvedTask.type === 'shell');
-        expect((<ProcessTaskConfiguration>resolvedTask).cwd).to.be.equal('/tmp/build2');
+        expect((<ProcessTaskConfiguration>resolvedTask).options!.cwd).to.be.equal('/tmp/build2');
         expect((<ProcessTaskConfiguration>resolvedTask).command).to.be.equal('very');
         expect((<ProcessTaskConfiguration>resolvedTask).args).to.deep.equal(['complex', 'command']);
     });

packages/cpp/src/browser/cpp-task-provider.ts

@@ -124,7 +124,9 @@ export class CppTaskProvider implements TaskContribution, TaskProvider, TaskReso
             type: 'shell',
             command,
             args,
-            cwd: task.config.directory,
+            options: {
+                cwd: task.config.directory,
+            }
         };
         return resolver.resolveTask(resolvedTask);
     }

packages/task/src/browser/quick-open-task.ts

@@ -283,7 +283,7 @@ export class TaskRunQuickOpenItem extends QuickOpenGroupItem {
         }
 
         if (this.taskDefinitionRegistry && !!this.taskDefinitionRegistry.getDefinition(this.task)) {
-            this.taskService.run(this.task.source, this.task.label);
+            this.taskService.run(this.task.source || this.task._source, this.task.label);
         } else {
             this.taskService.run(this.task._source, this.task.label);
         }

packages/task/src/browser/task-name-resolver.ts

@@ -15,7 +15,7 @@
  ********************************************************************************/
 
 import { inject, injectable } from 'inversify';
-import { TaskConfiguration } from '../common';
+import { TaskConfiguration, ContributedTaskConfiguration } from '../common';
 import { TaskDefinitionRegistry } from './task-definition-registry';
 
 @injectable()
@@ -28,11 +28,15 @@ export class TaskNameResolver {
      * It is aligned with VS Code.
      */
     resolve(task: TaskConfiguration): string {
-        if (this.taskDefinitionRegistry.getDefinition(task)) {
-            return `${task.source}: ${task.label}`;
+        if (this.isDetectedTask(task)) {
+            return `${task.source || task._source}: ${task.label}`;
         }
 
         // it is a hack, when task is customized but extension is absent
         return task.label || `${task.type}: ${task.task}`;
     }
+
+    private isDetectedTask(task: TaskConfiguration): task is ContributedTaskConfiguration {
+        return !!this.taskDefinitionRegistry.getDefinition(task);
+    }
 }