[all-commits] [llvm/llvm-project] b1eeec: [clang-format] Remove special logic for parsing co...

[Emilia Dreamer via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: b1eeec6177fafcc433d98c4f46f353b13c68aca0
      https://github.com/llvm/llvm-project/commit/b1eeec6177fafcc433d98c4f46f353b13c68aca0
  Author: Emilia Dreamer <emilia at rymiel.space>
  Date:   2023-01-06 (Fri, 06 Jan 2023)

  Changed paths:
    M clang/lib/Format/TokenAnnotator.cpp
    M clang/lib/Format/UnwrappedLineParser.cpp
    M clang/lib/Format/UnwrappedLineParser.h
    M clang/unittests/Format/FormatTest.cpp

  Log Message:
  -----------
  [clang-format] Remove special logic for parsing concept definitions.

Previously, clang-format relied on a special method to parse concept
definitions, `UnwrappedLineParser::parseConcept()`, which deferred to
`UnwrappedLineParser::parseConstraintExpression()`. This is problematic,
because the C++ grammar treats concepts and requires clauses
differently, causing issues such as https://github.com/llvm/llvm-project/issues/55898 and https://github.com/llvm/llvm-project/issues/58130.

This patch removes `parseConcept`, letting the formatter parse concept
definitions as more like what they actually are, fancy bool definitions.

NOTE that because of this, some long concept definitions change in their
formatting, as can be seen in the changed tests. This is because of a
change in split penalties, caused by a change in MightBeFunctionDecl on
the concept definition line, which was previously `true` but with this
patch is now `false`.

One might argue that `false` is a more "correct" value for concept
definitions, but I'd be fine with setting it to `true` again to maintain
compatibility with previous versions.

Fixes https://github.com/llvm/llvm-project/issues/58130

Depends on D140330

Reviewed By: HazardyKnusperkeks, owenpan, MyDeveloperDay

Differential Revision: https://reviews.llvm.org/D140339


  Commit: d9899501576e7b3b8ec4a3f0f855a6bfe68cef88
      https://github.com/llvm/llvm-project/commit/d9899501576e7b3b8ec4a3f0f855a6bfe68cef88
  Author: Emilia Dreamer <emilia at rymiel.space>
  Date:   2023-01-06 (Fri, 06 Jan 2023)

  Changed paths:
    M clang/lib/Format/UnwrappedLineParser.cpp
    M clang/unittests/Format/FormatTest.cpp
    M clang/unittests/Format/TokenAnnotatorTest.cpp

  Log Message:
  -----------
  [clang-format] Disallow decltype in the middle of constraints

If a function with a `requires` clause as a constraint has a decltype
return type, such as `decltype(auto)`, the decltype was seen to be part
of the constraint clause, rather than as part of the function
declaration, causing it to be placed on the wrong line.

This patch disallows decltype to be a part of these clauses

Fixes https://github.com/llvm/llvm-project/issues/59578

Depends on D140339

Reviewed By: HazardyKnusperkeks, owenpan, MyDeveloperDay

Differential Revision: https://reviews.llvm.org/D140312


Compare: https://github.com/llvm/llvm-project/compare/54fab18cedac...d9899501576e