Function Host Debugger View

[nturinski]

This PR adds a Function Host Debug view to the Azure Functions extension. The view appears in the Run and Debug panel and lists running Function Host tasks along with their recent error output.

A new tree view provider backs this view and supplies nodes for active hosts and error entries. The view includes commands to refresh the data, clear recorded errors, view or copy recent logs, and send an error to Copilot. These commands are available from the view toolbar and node context menus.

The PR also introduces a setting to always show the Function Host Debug view, regardless of context.

Supporting changes include exporting shared utilities for identifying host error logs and cleaning log output, extending command handling to accept argument arrays, and updating the Functions task provider to allow additional CLI arguments in task definitions.

No host running (only visible if always show setting is enabled)

Function host running with no errors

Function host running with an error

Location of Ask Copilot context menu

[nturinski]

@copilot Do another PR review

[Copilot]

@nturinski I've opened a new pull request, #4928, to work on those changes. Once the pull request is ready, I'll request review from you.

[alexweininger]

task.scope can be a TaskScope enum value (just a number), not only a WorkspaceFolder. Casting it here without checking means .uri?.path evaluates to undefined, and String.replace() will happily coerce that to the literal string "undefined" — so you'd end up with paths like /some/path/undefined/sub instead of the original unresolved string.

We already do the right typeof check in registerFunctionHostDebugView.ts, so maybe something like:

const workspacePath = typeof t.taskExecution.task?.scope === 'object'
    ? (t.taskExecution.task.scope as vscode.WorkspaceFolder).uri?.path
    : undefined;
const taskDirectory = workspacePath
    ? taskExecution.options?.cwd?.replace('${workspaceFolder}', workspacePath)
    : taskExecution.options?.cwd;
const resolvedBuildPath = workspacePath
    ? buildPath?.replace('${workspaceFolder}', workspacePath)
    : buildPath;

[alexweininger]

these emitters are never disposed

[nturinski]

Yeah, the issue is that we need to create them when the extension is activated, and if we dispose them after a function host task is terminated, they never get instantiated again.

I went ahead and disposed them on deactivation, which I think should happen anyway, but just to be explicit.

[MicroFish91]

I'm still getting the issue where the Functions Host Debugger view appears for a second and then immediately disappears (hides) after hitting F5, does this repro for anyone else?

[nturinski]

I'm still getting the issue where the Functions Host Debugger view appears for a second and then immediately disappears (hides) after hitting F5, does this repro for anyone else?

In light of this issue, I did the following:

Debugger View is always visible, but it collapsed by default.
Debugger View gets focused if the user is debugging and the function host has an error.
It only gets focused on the FIRST error.

[MicroFish91]

Is there much of a difference between "clear function host errors" and "clear stopped sessions"? I'm wondering if we can get rid of the first one if they end up roughly doing the same since (assuming what gets populated here are errors by default).

[MicroFish91]

Maybe a future todo, but consider splitting up the getChildren methods for each tree item out into their own class logic so that there is less code intersection in the tree data provider's get children method

[nturinski]

Is there much of a difference between "clear function host errors" and "clear stopped sessions"? I'm wondering if we can get rid of the first one if they end up roughly doing the same since (assuming what gets populated here are errors by default).

In practice, probably not. My initial thought was you may want to clear just the errors during a live session, but keep the old sessions? I'm not sure how realistic that is. At the very least, they don't need to both be ribbon buttons.