Clear promptInput's value onCommandFinished

[anthonykim1]

Resolves: microsoft/vscode-python-environments#640
Coming from: microsoft/vscode-python-environments#1093 (comment)

From: microsoft/vscode-python-environments#1093 (comment)

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I couldnt seem to repro ^C to show up on Python file run on Mac, but only on Windows.

This is happening because we have some extra polling happening before onCommandStarted event gets fired:

vscode/src/vs/platform/terminal/common/capabilities/commandDetectionCapability.ts

Line 727 in 86db4eb

this._tryAdjustCommandStartMarkerScheduler = new RunOnceScheduler(() => this._tryAdjustCommandStartMarker(initialCommandStartMarker), AdjustCommandStartMarkerConstants.Interval);

Which is what leads to resetting the value of promptInputModel:

We need the promptInputModel's value to be empty and state to be not execute in order to not cause ^C upon executeCommand run:

vscode/src/vs/workbench/contrib/terminal/browser/terminalInstance.ts

Line 1010 in 86db4eb

if (shouldExecute && (!commandDetection || commandDetection.promptInputModel.value.length > 0)) {

So in that meantime before we clear the value of promptInput to empty string, the state will be execute and value of it will point to activation script. Which will lead to ^C.

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Flow from env extension:
Send activate command -> wait for onDidEndShellExecution -> send file execution.

The ctrl^c came from second arrow.

[Copilot]

Pull request overview

This PR adds support for clearing the prompt input model's value when a command finishes executing. This change prevents the runCommand API from detecting leftover text from a previous command and unnecessarily sending a ^C interrupt signal.

Changes:

• Added onCommandFinished event subscription to PromptInputModel to clear the input value after command completion
• Updated the constructor and test setup to wire the new event handler
• Added test coverage to verify the value is cleared when a command finishes

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 6 comments.

File	Description
src/vs/platform/terminal/common/capabilities/commandDetection/promptInputModel.ts	Added onCommandFinished event parameter and _handleCommandFinished method to clear prompt input value
src/vs/platform/terminal/common/capabilities/commandDetectionCapability.ts	Updated PromptInputModel instantiation to pass onCommandFinished event
src/vs/platform/terminal/test/common/capabilities/commandDetection/promptInputModel.test.ts	Added test setup for onCommandFinished emitter and test case to verify value clearing behavior

[anthonykim1]

I'm not sure if it will be good idea to fire an empty _onDidChangeInput here, because we havent started the "new" input yet.

[Tyriar]

Since we're changing the value, let's fire it to be consistent and see if there are any problems.