code-completion doesn't replace expected text when cursor is not at the end of name

[DanTup]

• VSCode Version: 1.4.0
• OS Version: Windows 10

Steps to Reproduce:

1. Create a method called methodOne
2. Write some code that calls this method as methodTwo()
3. Place the cursor between the d and T and invoke completion
4. Select methodOne from the completion list

You would expect methodTwo to be replaced with methodOne but you end up with methodOneTwo.

[dbaeumer]

@jrieken is there anything special I need to do to achieve this?

[DanTup]

If it helps, my Dart extension seems to handle this correctly:

https://github.com/DanTup/Dart-Code/blob/master/src/dart_completion_item_provider.ts#L41

You can provide a textEdit property on the CompletionItem with a Range to replace. The Dart language service I'm using already returned the correct length here so it just worked out of the box. I guess in your MyCompletionItem class you may need to set up the textEdit (assuming you have all the necessary info from the service).

[dbaeumer]

I don't :-(. I can reconstruct this using may be model API but I was hoping not being forced to do this and @jrieken knows a better way.

If we need this information to handle cases like this then it should IMO come from the tsserver since he has the full knowledge about the context of the code complete.

[jrieken]

When a completion item doesn't specify a text edit we construct one with the word range until the current position. So, you can achieve the behaviour using a different range or we just change our default - tho that makes it sound more like a user option cos I am not sure if overwrite after is always the right thing to do?

[dbaeumer]

Changing the default is not a good thing to do since we will break others. I will see if I can recompute this for now and make a request against the tsserver to better provide this info.

[jrieken]

You can always ask for the word range at position. That's usually a pretty good guess

[dbaeumer]

Agree.

[dbaeumer]

@jrieken and I discussed that again over lunch and we agreed that we should investigate into a language neutral solution to not have to many language specific settings. Moving to September and adding @jrieken as an owner.

[ramya-rao-a]

Related to #4878 ?

[jrieken]

Your understanding is wrong - when extensions provide a range nothing will change.

[DanTup]

Ok, then I'm confused - why hold it back? It sounds like rolling it out will have no change in behaviour at all, and a change will only come when extensions update to the new API (which they can't do until after you ship it)?

[jrieken]

We wanted to make sure that at least the extensions that ship with VS support this. Otherwise we should ship a setting that's not doing anything.

[DanTup]

Got it, thanks 👍

[jrieken]

@bmewburn re #10266 (comment). This is good feedback and wrt insert I would say that it's OK to end up with invalid code, e.g having con|sole and insert-accepting const simply results in constsole and I feel that this logic shouldn't change when accepting a suggestion that includes the invocation part. Tho, having said that - the API is designed to allow extensions to say "nah, in this case only replace or insert makes sense". Eg. your extension can provide insert and replace ranges for variable name suggestions but only replace ranges for invocation suggestions. We won't massage anything onto the ranges in that case and the UI will only offer one way of inserting. What we have planned here is to make it visible what is going to replaced, e.g rendering some background treatment.

[jrieken]

We not gotten enough feedback to finalise this API and will push things out for another milestone. Tho, the setting and the default behaviour will ship.

[ctf0]

isnt this covered with "editor.suggest.insertMode": "replace"

[DanTup]

@ctf0 that functionality only works if the language extension provides two ranges to VS Code. There's an issue tracking handling that for TS at #87091.