Allow file system provider schemes to participate in history even after close

[gjsjohnmurray]

Issue Type: Bug

I work on a team developing an extension that implements a FileSystemProvider and a DocumentSymbolProvider.

If the user opens file1 in preview mode (italic tab label), then used F12 when on a symbol defined in file2, this correctly loads file2 in the same tab. But the 'Back' option on the 'Go' menu doesn't get enabled.

I think it is caused by this code executing when file2 replaces file1 in the preview tab:

vscode/src/vs/workbench/services/history/browser/history.ts

Lines 508 to 512 in 0ea7e1c

	// Remove this from the stack unless the stack input is a resource
	// that can easily be restored even when the input gets disposed
	if (stackEditorInput instanceof EditorInput) {
	this.onEditorDispose(stackEditorInput, () => this.removeFromNavigationStack(stackEditorInput), this.editorStackListeners);
	}

in combination with this logic which didn't turn the 'Go to Definition' history entry into one that points to a ResourceEditorInput because it only does that for a limited range of uri schemes:

vscode/src/vs/workbench/services/history/browser/history.ts

Lines 518 to 527 in 0ea7e1c

	private preferResourceEditorInput(input: IEditorInput): IEditorInput | IResourceEditorInput {
	const resource = EditorResourceAccessor.getOriginalUri(input);
	if (resource && (resource.scheme === Schemas.file || resource.scheme === Schemas.vscodeRemote || resource.scheme === Schemas.userData || resource.scheme === this.pathService.defaultUriScheme)) {
	// for now, only prefer well known schemes that we control to prevent
	// issues such as https://github.com/microsoft/vscode/issues/85204
	return { resource };
	}
	return input;
	}

@bpasero is this your area?

I tried to devise a repro using fsprovider-sample by adding file2.ts to the workspace, exporting a function from it, then referencing it from file.ts. But the 'Initializing JS/TS language features' message never cleared, so I assume JS/TS language support can't handle files provided by the MemFS FileSystemProvider.

VS Code version: Code 1.50.1 (d2e414d, 2020-10-13T15:06:15.712Z)
OS version: Windows_NT x64 10.0.18363

[bpasero]

Yes, we have limited the support for navigation in history to schemes we know but can think about revisting this.

[gjsjohnmurray]

I previously wrote:

I tried to devise a repro using fsprovider-sample by adding file2.ts to the workspace, exporting a function from it, then referencing it from file.ts. But the 'Initializing JS/TS language features' message never cleared, so I assume JS/TS language support can't handle files provided by the MemFS FileSystemProvider.

Probably #108454

[bpasero]

With 36e2868 this situation improved a bit: we now remove the "preview" state of an editor when it is the source of a navigation action such as "Goto definition", as such the functionality of navigating in history will work even for custom file schemes.

[vscodenpa]

We closed this issue because we don't plan to address it in the foreseeable future. If you disagree and feel that this issue is crucial: we are happy to listen and to reconsider.

If you wonder what we are up to, please see our roadmap and issue reporting guidelines.

Thanks for your understanding, and happy coding!