[clang] 8b48d24 - [clang-format] Recognize c++ coroutine keywords as unary operator to avoid misleading pointer alignment

[Chuanqi Xu via cfe-commits]

Author: Chuanqi Xu
Date: 2020-12-15T20:50:46+08:00
New Revision: 8b48d24373204fc2fe6aac1f1f850fa3b6c18445

URL: https://github.com/llvm/llvm-project/commit/8b48d24373204fc2fe6aac1f1f850fa3b6c18445
DIFF: https://github.com/llvm/llvm-project/commit/8b48d24373204fc2fe6aac1f1f850fa3b6c18445.diff

LOG: [clang-format] Recognize c++ coroutine keywords as unary operator to avoid misleading pointer alignment

Summary: The clang-format may go wrong when handle c++ coroutine keywords and pointer.
The default value for PointerAlignment is PAS_Right. So the following format is good:
```
co_return *a;
```
But within some code style, the value for PointerAlignment is PAS_Left, the behavior goes wrong:
```
co_return* a;
```

test-plan: check-clang

reviewers: MyDeveloperDay

Differential Revision: https://reviews.llvm.org/D91245

Added: 
    

Modified: 
    clang/lib/Format/TokenAnnotator.cpp
    clang/unittests/Format/FormatTest.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index b1c9c37a8ed9..821b46b75f6b 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -1964,6 +1964,7 @@ class AnnotatingParser {
 
     if (PrevToken->isOneOf(tok::l_paren, tok::l_square, tok::l_brace,
                            tok::comma, tok::semi, tok::kw_return, tok::colon,
+                           tok::kw_co_return, tok::kw_co_await, tok::kw_co_yield,
                            tok::equal, tok::kw_delete, tok::kw_sizeof,
                            tok::kw_throw) ||
         PrevToken->isOneOf(TT_BinaryOperator, TT_ConditionalExpr,

diff  --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 1c78b6e2cb1e..a3dbec9a669f 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -7755,6 +7755,15 @@ TEST_F(FormatTest, UnderstandsUnaryOperators) {
 
   verifyFormat("co_yield -1;");
   verifyFormat("co_return -1;");
+
+  // Check that * is not treated as a binary operator when we set PointerAlignment
+  // as PAS_Left after a keyword and not a declaration.
+  FormatStyle PASLeftStyle = getLLVMStyle();
+  PASLeftStyle.PointerAlignment = FormatStyle::PAS_Left;
+  verifyFormat("co_return *a;", PASLeftStyle);
+  verifyFormat("co_await *a;", PASLeftStyle);
+  verifyFormat("co_yield *a", PASLeftStyle);
+  verifyFormat("return *a;", PASLeftStyle);
 }
 
 TEST_F(FormatTest, DoesNotIndentRelativeToUnaryOperators) {