Add hover cards and jump to declaration / definition / reference for the
formatted SemIR that appears in check tests. This is done by adding a
heuristic "parser" for SemIR to the language server. The
cross-references are strictly best-effort, since this is just a tool for
Carbon developers, not a user-facing facility.
A couple of other changes made along the way:
* file_test tests with an AUTOUPDATE-SPLIT no longer look for CHECK:
lines outside that split. This was motivated by the tests for this new
facility including CHECK: lines as part of the test input.
* An agent skill for working on the language server, tracking some
things that cost Claude time when working on this.
Assisted-by: Claude via Antigravity
Implements formatting support within LSP. Current implementation
performs while file formatting, we just replace file with output of
Carbon::Format()
https://github.com/carbon-language/carbon-lang/pull/7687 independently
improves formatting so that this output is somewhat decent.
Assisted-With: Gemini / Antigravity
Add support for "jump to declaration", "find references", type
information on hover. This support is strictly single-file for now; only
references and declarations within the same file are found. We could go
a bit beyond that, but to properly handle cross-file references we'll
need to build an index and a compilation database, which is beyond the
scope of this change.
On hover, we provide the type information for the instruction under the
cursor as-is. This is frequently not very useful, as the type of a
function F is simply "<type of F>", but is a starting point for richer
information.
Assisted-by: Claude Code
We currently provide UTF-8 positions, since our source representation is
UTF-8 and we use byte offsets as column numbers, but the LSP protocol
default is UTF-16 column positions. Negotiate UTF-8 positions where
possible; this is supported by essentially every LSP client other than
VS Code.
In the case where we select a UTF-16 position, we continue to not do any
actual conversions, so our column offsets in such cases will continue to
be wrong on non-ASCII source files in VS Code.
Assisted by: Claude Code
The language server is now able to subscribe to and apply incremental
changes to the document. Source code is assumed to be utf-8. It does not
currently handle utf-16 code points.
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Co-authored-by: Carbon Infra Bot <carbon-external-infra@google.com>
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Richard Smith
DavidLoftus
Jon Ross-Perkins
