Code Folding

[angelozerr]

TextMate grammar can define folding https://manual.macromates.com/en/navigation_overview

It should be cool if tm4e could provide the org.eclipse.tm4e.ui.folding.TMFoldingStrategy which supports this feature.

[mickaelistria]

Do you have an estimation of the ratio of textmate grammars that do enable folding? does VSCode rely on it ?

[angelozerr]

Do you have an estimation of the ratio of textmate grammars that do enable folding? does VSCode rely on it ?

To be honnest with you, I don't remember. I must study again that but I'm very busy for the moment with JDT Codelens (an another project/topic).

[angelozerr]

@micktaelistria the only thing that I can tell you is that VSCode uses by default the indent folding strategy that I have implemented for Eclipse https://github.com/angelozerr/typescript.java/blob/master/eclipse/ts.eclipse.ide.ui/src/ts/eclipse/ide/ui/folding/IndentFoldingStrategy.java

Inside VSCode TypeScript, JSON, etc editor uses this folding strategy. I know you are working on folding feature for Generic Editor. IMHO, I think Generic Editor should use this indent folding strategy by default.

[mickaelistria]

I think Generic Editor should use this indent folding strategy by default.

I agree. Now that Generic Editor has an extension point for reconciler and an example about folding, it shouldn't be that hard to add it. Can you please open an enhancement request for that?

[angelozerr]

Can you
please open an enhancement request for that?

This bug exists https://bugs.eclipse.org/bugs/show_bug.cgi?id=512956

[mickaelistria]

This bug exists https://bugs.eclipse.org/bugs/show_bug.cgi?id=512956

That bug is about providing the extension-point, not about providing some (default) implementation.

[angelozerr]

That bug is about providing the extension-point, not about providing some (default) implementation.

Done https://bugs.eclipse.org/bugs/show_bug.cgi?id=520659

[bartoszbinda]

Was it implemented in tm4e? How can I use it in generic editor to fold/unfold yaml or json?

[angelozerr]

Today tm4e doesn't support code folding, but I tell me if it's a good idea since LSP4E supports now folding. For instance json language server supports folding. For yaml, I don't know.

[norru]

What's the status of this?

[mickaelistria]

Still open, looking for volunteers to fix it.
But as @angelozerr mentions, LSP4E now supports folding, so there is less value in using TM4E for that.

[sebthom]

It looks like some kind of folding now happens even without LSP, but it seems to be broken.

For toml only two sections are marked as foldable:

For a cpp file the wrong lines are folded:

[cabintech]

Humm, no activity on folding support in the TM4E language configuration for a long while... would really like this but have way too little experience in Eclipse infrastructure to do it myself. It's a shame because the folding data is read from the language support file and shown in the UI - it just does not work (which is maybe worse than no support at all... spent a lot of time trying to get it to work before I found out it is actually not supported).

[Edit - updated to latest Eclipse version 2024.05 and I see there is a language config file for JSON and sure enough, when a .json file is opened with the Generic editor it has folding. But the Preferences->TextMate->LanguageConfiguration UI shows no folding start/end values defined for JSON... so how is folding working for JSON files? Oh, seems the generic editor has some default folding support for {...}. Any way to configure that for my language?]