Problem

Function vscode.tasks.fetchTasks in Theia works different than in VSCode. Task provided by Task Provider are fetched correcly, but if this task saved in tasks configuration (tasks.json) it's fetched in VSCode and not fetched in Theia.

How to reproduce in VSCode

1. Clone this project.
2. Open this project in VSCode (I used v1.46.1).
3. Run npm install and npm run compile.
4. Run Extension from the Run View.
5. In the Extension Development Host window open folder testdata of this project.
6. Open Output view
7. From the command palette select command fetch echo tasks.
8. Select output channel named echo-channel.
9. Ensure that 3 tasks are provided: Detected task 1 Detected task 2 Configured task 3
10. This is expected behavior
11. For further reprodicing in Theia package this project with command: vsce package. File echotaskprovider-0.0.1.vsix will be created in the root of the project.

How to reproduce in Theia

1. Open https://gitpod.io/#https://github.com/eclipse-theia/theia to start development with the master branch.
2. Gitpod will start a properly configured for Theia development workspace, clone and build the Theia repository.
3. After the build is finished,, upload echotaskprovider-0.0.1.vsix extension into folder plugin.
4. Run from the terminal in Gitpod: cd examples/browser && yarn run start ../.. --hostname 0.0.0.0.
5. Open localhost:3000.
6. In the Extension Development Host window open folder testdata of this project.
7. From the command palette select command fetch echo tasks.
8. Select output channel named echo-channel. 9 Ensure that only 2 tasks are provided: Detected task 1 Detected task 2

Workaround

1. Change the Configured task 3 task in tasks.json file adding property "taskType": "".
2. Save the file.
3. Run command fetch echo tasks.
4. All 3 tasks are fetched now.