At present, we typically define a DiagnosticConverter, then store an
instance of it and a DiagnosticEmitter that wraps it. This is relatively
minor in general, but I've been trying to create more self-contained
DiagnosticEmitter classes (which hold their own DiagnosticConverter,
similar to NullDiagnosticEmitter), and there it just gets in the way.
Since we don't reuse DiagnosticConverter instances, this combines the
definition into DiagnosticEmitter. Mainly this means we don't have a
separate object in play, and less to carry around.
The most impact is probably to SemIRDiagnosticConverter, which was also
the most complex. Now `SemIRLocDiagnosticEmitter`, this gets some
different construction flow. Note in the PR I've split the file rename
to its own commit, to try to help delta views. However, the most
substantial parts of the refactoring are split into #4876, which this
depends upon.
Pursuant to discussion regarding #4699, turn on
`misc-non-private-member-variables-in-classes` using the
`IgnoreClassesWithAllMemberVariablesBeingPublic` flag (the check treats
structs as classes, so we need this for structs with all-public
members). Updates the style guide notes to match, which should be pretty
minor due to the scoping of test fixtures.
Also fixes some underscore uses in test files on the way. Basically this
is keeping the style for [class data member
naming](https://google.github.io/styleguide/cppguide.html#Variable_Names)
even while making them public.
Since the addition of TranslateArg, I don't think this type is going to
go away (cutting a TODO). Refactoring names slightly to fit the current
role, and adding const to ConvertLocation.
Building on #3311, which started moving the result string into a
`unique_ptr`, instead have `StringLiteral` use a `BumpPtrAllocator` to
manage memory. But also, detect when a string is really trivial during
`Lex` and, if so, return `contents_` directly.
Rationale: this convention avoids forcing closely-related code to be far
apart in the namespace hierarchy, and vice versa. By the same token, it
makes the namespace hierarchy more consistent with the directory
hierarchy.
Continuing with #3070. Just a dir and file rename (only prefix change is
lexer_file_test). Everything in the lex dir should be marked as a move.
Note, I think this closes#3070. There may still be further cleanup
later, but the organizational changes suggested there are being
completed.
---------
Co-authored-by: Chandler Carruth <chandlerc@gmail.com>
Jon Ross-Perkins
Geoff Romer
