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.
---------
Co-authored-by: Chandler Carruth <chandlerc@gmail.com>
Mainly, changes the default from -1 to 0 in DiagnosticLoc, still trying
to keep reusing that. Nothing except for the lowered output is affected,
so I think this is fine.
Also, have lowering consistently call GetDiagnosticLoc.
Pulls in one of the CHECKs suggested from #4251
Co-authored-by: David Blaikie <dblaikie@gmail.com>
I'm trying to make the line of code more clearly nested in crash output
(the way it is, I sometimes forget about it). Also,
`Check::HandleFunctionDecl` is the old naming scheme, it's now all
`Check::HandleParseNode`, so I'm replacing that.
Before:
```
3. extern_library_owner.carbon:6:1: Check::HandleFunctionDecl
extern fn F();
^~~~~~~~~~~~~~
#0 0x0000564c0057ef1d llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) ...
```
After:
```
3. extern_library_owner.carbon:6:1: checking FunctionDecl
extern fn F();
^~~~~~~~~~~~~~
#0 0x00005629029ffd9d llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) ...
```
When we crash, include the source location of the parse node that we
were handling, as well as the name of the check function that we were
calling. Also include the source snippet, since it's easy to do so, and
may avoid the need to look at the input file in some cases.
Jon Ross-PerkinsandChandler Carruth
josh11bandJosh L
Richard Smith