Automatically run build_runner on VS Code startup, not working

An issue for a problem, which came up in this issue: https://github.com/Dart-Code/Dart-Code/issues/1211#issuecomment-470621513

Here is my project: intersect.zip

@DanTup Yes, at least sort of.

I wanted to start the watch task as soon as I open VS Code. So I did the following:

1. STRG + SHIFT + P
2. Typed: “Tasks Configure Task” ENTER
3. Selected, the Task I wanted to configure
4. Modified generated task.json to the following (only added "runOptions"):

Now there is a warning:

Incorrect type. Expected “object”.

And when I restart Visual Studio I get an error notification and following output:

Error: The pub task detection didn’t contribute a task for the following configuration: { “type”: “pub”, “command”: “watch”, “problemMatcher”: [ “dart-pub-build_runner” ], “runOptions”: { “runOn”: “folderOpen” } } The task will be ignored.

Similar to this one: https://github.com/dart-lang/build/issues/1025#issuecomment-435993458

Any idea?

[DanTup]

I think between a fix made in https://github.com/microsoft/vscode/issues/70303 and https://github.com/microsoft/vscode/issues/126238, this should be fixable now, though requires us to adopt the new onTaskType: activation event.

[DanTup]

Ok, I’m waiting to hear back on https://github.com/Microsoft/vscode/issues/70303 before doing any more on this. In my opinion this is a bug - it should not be necessary for an extension that uses tasks to have to activate whenever the user runs any task in VS Code (especially given they don’t seem to want to give us an activation reason).

I hope we could have a more restricted activation event (eg. onTask:pub).