Editable TextDocumentContentProvider for extensions

[anorborg]

I'm just getting started with extension development so please forgive me if this is a inappropriate feature request. I'm looking to create an extension that with allow me to select a block of code in a source language (i.e. html) and have the option to edit the block in a different language (i.e. jade/pug). I would imagine it would behave similarly to the TextDocumentContentProvider, but have the ability to edit in the secondary window, then transpile back to the source when completed. I didn't see anything in the API documents that would allow me to do this now. Thanks.

[jrieken]

You can do that by adding the onDidChange event to your provider. A sample is this: https://github.com/Microsoft/vscode-extension-samples/blob/master/previewhtml-sample/src/extension.ts#L13

[anorborg]

Apologies if I'm misunderstanding Johannes Rieken (@jrieken), but doesn't that refer to changes in the source document? I'm looking to allow editing in secondary (in the example you gave me, preview window). The TextDocumentContentProvider documentation seems to explicitly state "readonly documents".

[jrieken]

but doesn't that refer to changes in the source document?

Yes, but if you make the document 'render' using the previewHtml command it will also update

[anorborg]

I don't think I'm being clear, so again I apologize. Let me try to explain the use case I'm trying to accomplish in detail. If I have a source document in html, source.html, I want to highlight a code block, for example:

<div class="form-group">
    <input class="form-control" id="oldId" value="test" />
</div>

I then want to be able to execute a command like "Edit As Pug/Jade" which will open a secondary editor window that will automatically transpile to something like the following:

.form-group
    input.form-control#oldId(value="test")

In that secondary editor window I would update the pug/jade code to something like the following (updating the id field):

.form-group
    input.form-control#newId(value="test")

I then would execute another command indicating I'm done editing that would close the secondary editor window and the source document, source.html, would be update based off the changes made in the Pug/Jade to the following HTML:

<div class="form-group">
    <input class="form-control" id="newId" value="test" />
</div>

Notice that the id field was changed based on the changes made in the secondary editor window.

Again I do apologize if I'm missing your explanation, but based on the code and the example you've pointed to, it seems I hadn't quite explained what I was trying to accomplish correctly.

[jrieken]

Ah, thanks now I get it. We don't support that users make changes in virtual documents and I am also unsure what that would mean... You could work around this by making a 'untitled' to 'temp' document somewhere

[eamodio]

Johannes Rieken (@jrieken) can this be reopened as a feature request? Supporting editable virtual documents could be pretty useful in certain scenarios.

For example: https://github.com/pprice/vscode-better-merge/issues/25

Quick summary -- using editable virtual documents to compare changes and (manually) sync the edits back to the main document.

An alternative request could be supporting virtual documents that are actually "windows" (a slice) of a real document. But that sounds much more complicated and less broadly applicable.

[jrieken]

Ok, valid request after all. Unsure yet how the API will look like, maybe just offering a save method on your provider is enough. That would make it editable and we will call that method when going through our 'normal' save.