Allow extensions to participate in file rename/move operations

[DanTup]

Many languages import files by filename:

import "myfile.dart";

If a user renames this file using explorer, the code references to it become broken and need fixing up. The Dart language server has support for returning the code edits required during a file rename to avoid this. As far as I can see there isn't an API for this yet.

I think could be useful for many languages (Dart, JS, TS, maybe even HTML's script tags/link tags!).

[jrieken]

Do you want to be part of the rename-file-command or just have an event/file-event that tells you something has been renamed?

[DanTup]

Based on the language server docs:

The refactoring must be activated before an actual file moving operation is performed.

I guess I'd need to know before it happened (I guess once the rename has happened, it may not be able to figure out the changes required). The API in theory could return errors, so it may be worthwhile allowing cancellation of it with some sort of message, though I don't know whether that's actually a possibility in the implementation (their MOVE_FILE is part of a refactor API which handles other things so the API is somewhat generic).

[jrieken]

Thanks for clarifying - I have updated the title accordingly

[mjbvz]

TS just merged an API for rename file: microsoft/TypeScript#23573

Cases we'd need events for:

• Rename file in explorer
• Drag and drop file between folders in explorer

If we want to allow extensions to react to renames (this is how TS API is designed to be used), the expected API could be something like:

onDidRenameFile: Event<{ oldResourceLocation: Uri, newResourceLocation: Uri }>

If we want extensions to be able to participate in the rename itself, we'd need a new hook (or possibly a new provider)

I'd say we should only handle renames in the explore and not try to handle renames outside of the editor or try making this API part of the FileWatcher. This should simplify the implementation while still covering most of the use cases for triggering actions based on file renames

[DanTup]

I'd say we should only handle renames in the explorer

This sounds reasonable to me; however to handle this for Dart we really need to be called before the rename occurs; onDidRenameFile will be too late.

[jrieken]

I'd say we should only handle renames in the explore and not try to handle renames outside of the editor or try making this API part of the FileWatcher.

Agreed, but going a step further to say this is shouldn't be depend on events at all. When moving a file (via whatever user-gesture) we should now that there is a move/rename participant that we need to involve in the process. And it should probably not be the default (or behind a prompt) so that you still move a file without the smarts

[mjbvz]

Related to #24846