Adds @LSP-CALL and refactors LSP keyword handling to implicitly handle a
little more of the LSP structure. This is coming out of textDocument
call handling, where this at least reduces some boilerplate of
`"params": {...}`.
Not sure if I mixed up a merge somewhere, but this is what
`parse_error.carbon` was supposed to test. Note
`unexpected_reply.carbon` was basically doing the same test, with a
minor issue of `change` vs `result` to get better output.
This switches most error printing to use diagnostics instead of direct
stream writes, even when not a specific file diagnostic. I'm allowing
empty filenames for this use-case.
This allows a little more specific testing to validate coverage of
output using the diagnostic coverage test. I'm adding a few tests to
cover things that weren't previously tested.
Separately, this also forces a little more standardization in format...
considering how changes like #4568 show effort being spent to _mirror_
diagnostic style, my thought is now to just use diagnostic code where
possible.
Note this also allows incrementally better testing of the language
server; I'm changing the crash fix from #4847 in favor of diagnostic
testing.
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Co-authored-by: Chandler Carruth <chandlerc@gmail.com>
Jon Ross-Perkins
