Debug: being asked to save a file on F5

[bpasero]

• Do normal extension development
• Step into code from extension host (i.e. not the extension)
• Stop debugging
• While code from extension host is visible, press F5

=> 🐛 you are being asked to save the file

[bpasero]

[connor4312]

This actually looks intentional:

vscode/src/vs/workbench/contrib/debug/browser/debug.contribution.ts

Lines 519 to 529 in 7d10ad3

	'debug.saveBeforeStart': {
	description: nls.localize('debug.saveBeforeStart', "Controls what editors to save before starting a debug session."),
	enum: ['allEditorsInActiveGroup', 'nonUntitledEditorsInActiveGroup', 'none'],
	enumDescriptions: [
	nls.localize('debug.saveBeforeStart.allEditorsInActiveGroup', "Save all editors in the active group before starting a debug session."),
	nls.localize('debug.saveBeforeStart.nonUntitledEditorsInActiveGroup', "Save all editors in the active group except untitled ones before starting a debug session."),
	nls.localize('debug.saveBeforeStart.none', "Don't save any editors before starting a debug session."),
	],
	default: 'allEditorsInActiveGroup',
	scope: ConfigurationScope.LANGUAGE_OVERRIDABLE
	},

But regardless of the active group configuration, we already call saveAll() which excludes untitled editors, so this is kind of confusing...

vscode/src/vs/workbench/contrib/debug/common/debugUtils.ts

Lines 312 to 325 in e7b3724

	export async function saveAllBeforeDebugStart(configurationService: IConfigurationService, editorService: IEditorService): Promise<void> {
	const saveBeforeStartConfig: string = configurationService.getValue('debug.saveBeforeStart', { overrideIdentifier: editorService.activeTextEditorMode });
	if (saveBeforeStartConfig !== 'none') {
	await editorService.saveAll();
	if (saveBeforeStartConfig === 'allEditorsInActiveGroup') {
	const activeEditor = editorService.activeEditorPane;
	if (activeEditor) {
	// Make sure to save the active editor in case it is in untitled file it wont be saved as part of saveAll #111850
	await editorService.save({ editor: activeEditor.input, groupId: activeEditor.group.id });
	}
	}
	}
	await configurationService.reloadConfiguration();
	}

I think nonUntitledEditorsInActiveGroup should be the default. This default is rather annoying imo, I use untitled editors as scratch buffers frequently. And I think this only started working this way recently, in the last couple months.

cc @isidorn

[roblourens]

So that file that came from the DA is an "untitled" file?

[roblourens]

Same issue: #117949
and original discussion in #114890

I think maybe there are people writing some code in an untitled editor, then starting a launch config that references ${file} and we can help them by making them save the file. We can probably distinguish between files that are actually Untitled-1 vs these untitled files with names right?

[connor4312]

Yea, that's a refinement. But I'm curious how often it helps with correctly saving an untitled file versus the false-positive rate we get when prompting.

[roblourens]

I'm curious how often it helps with correctly saving an untitled file

I bet it's not uncommon especially in JS and Python

[bpasero]

So the culprit is this line:

vscode/src/vs/workbench/contrib/debug/common/debugUtils.ts

Lines 319 to 320 in e7b3724

	// Make sure to save the active editor in case it is in untitled file it wont be saved as part of saveAll #111850
	await editorService.save({ editor: activeEditor.input, groupId: activeEditor.group.id });

If you want to special case only untitled editors, you would have to probe the resource of the active editor (via EditorResourceAccessor) to be untitled scheme.

[connor4312]

I bet it's not uncommon especially in JS and Python

Could we only do this if ${file} is present in any of the unresolved launch configuration properties?

[roblourens]

What other scenarios did you have in mind @isidorn?

[isidorn]

@roblourens no other scenarios then what the comment mentions - make sure to save the untitled file. As @bpasero suggests we could look at the active file to check if it is untitled - that sounds reasonable.

The whole point of that change is for beginner users when they just press start coding in an untitled file and press F5 that we prompt them to save the file, thus enabling debugging once there is an extension.