Support multiple files in working copy file service

[DanTup]

When dragging multiple files in the explorer, the onWillRenameFiles event is fired multiple times concurrently with a single file per-call - even though the API supports an array:

vscode/src/vs/workbench/api/common/extHostFileSystemEventService.ts

Line 185 in 926fc23

await this._fireWillEvent(this._onWillRenameFile, { files: [{ oldUri: URI.revive(source!), newUri: URI.revive(target) }] }, timeout, token);

This means an extension will produce multiple edits for a single operation if there are multiple files moved - though it looks like VS Code merges them together:

vscode/src/vs/workbench/api/common/extHostFileSystemEventService.ts

Lines 219 to 228 in 926fc23

	if (edits.length > 0) {
	// flatten all WorkspaceEdits collected via waitUntil-call
	// and apply them in one go.
	const allEdits = new Array<Array<IWorkspaceFileEditDto | IWorkspaceTextEditDto>>();
	for (let edit of edits) {
	let { edits } = typeConverter.WorkspaceEdit.from(edit, this._extHostDocumentsAndEditors);
	allEdits.push(edits);
	}
	return this._mainThreadTextEditors.$tryApplyWorkspaceEdit({ edits: flatten(allEdits) });
	}

However, this fails if two of the edits modified the same file with "(file) has changed in the meantime".

Here's a gif showing individual file moves correctly updating the file on the right. However if I moved them both at the same time, only one edit is applied and the other one fails.

The code for that repro is available here:

https://github.com/DanTup/vscode-repro-will-rename-files (extension.ts).

[jrieken]

@bpasero, @isidorn Not sure if the working-copy service still needs support for this or if the explorer didn't adopt this yet

[bpasero]

@jrieken I was not aware there is support for an array of resources, e.g. when I look at $onWillRunFileOperation and $onDidRunFileOperation I can only pass in a single resource. But it would probably be easy enough to support an array here given the ext host side supports an array for the event.

This needs:

• support on the working copy file service to do operations on multiple resources
• adoption in places where we want to support this (e.g. explorer)

Setting help wanted if someone wants to do this, shouldn't be too complicated.

[pfongkye]

Hi @bpasero
I would like to work on this issue if nobody else is.

[bpasero]

Yes, go for it 👍

[isidorn]

@bpasero I see you are reviewing this. Feel free to assign me back if you need some help.

[bpasero]

@DanTup can you please verify your original issue is resolved with your test extension?

[DanTup]

Yes, this works! Thank you @pfongkye @bpasero! 😀

[pfongkye]

Yes, this works! Thank you @pfongkye @bpasero!

Great 😃
You're welcome.