Scala `for` indent

[thoradam]

In Scala indents don't work for empty fors because they aren't fully parsed at that point. To illustrate, if I'm here

def wat() = for {|}

and press enter it's not indented properly because at this point it's not fully parsed as a (for_expression) is TS and just comes up as an (ERROR). If I press enter inside a fully typed out for expression (with the yield and at least one <-) it works.

Matrix discussion

[Triton171]

I just tested it and it doesn't seem to require a yield to work correctly, only at least one <- expression after the for. For the case where this is also missing, adding something like this to the queries might be the simplest solution:

(ERROR
    "for") @indent

I'd recommend that you try some different combinations of nesting functions, (incomplete) for expressions, etc. and look at how the generated syntax tree looks (sometimes, the way that errors are parsed depends in weird ways on these combinations). Then, you can add patterns like the one above to handle as many of the common situations as possible. I unfortunately don't know any Scala, so I cannot easily debug this myself.

Of course this will never be perfect, especially if the tree-sitter grammar behaves weirdly. Usually, adding a few such patterns is enough to cover almost all situations that occur in practice however.

[janos-r]

I tried it with exactly

def wat() = for {|}

the cursor at the pipe position, and enter indents it as expected.