[llvm-branch-commits] [clang] release/20.x: [clang-format] Keep the space between `not` and a unary operator (#135035) (PR #135118)

[via llvm-branch-commits]

https://github.com/llvmbot created https://github.com/llvm/llvm-project/pull/135118

Backport f34483838937b1a01ee11ee22bdd6e13c81e9fff

Requested by: @owenca

>From 352ee2311f041ca08c1ff7bc4a68dd5094398951 Mon Sep 17 00:00:00 2001
From: Owen Pan <owenpiano at gmail.com>
Date: Wed, 9 Apr 2025 17:52:12 -0700
Subject: [PATCH] [clang-format] Keep the space between `not` and a unary
 operator (#135035)

Also keep the space between `not` and `::`.

Based on the
[documentation](https://releases.llvm.org/20.1.0/tools/clang/docs/ClangFormatStyleOptions.html#spaceafterlogicalnot),
it can be argued that SpaceAfterLogicalNot doesn't cover the alternative
operator `not`.

Closes #125465

(cherry picked from commit f34483838937b1a01ee11ee22bdd6e13c81e9fff)
---
 clang/lib/Format/TokenAnnotator.cpp   | 7 ++++++-
 clang/unittests/Format/FormatTest.cpp | 5 +++--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index 976c4d888e1fd..7ad99b7a9660c 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -5437,7 +5437,12 @@ bool TokenAnnotator::spaceRequiredBefore(const AnnotatedLine &Line,
     // handled.
     if (Left.is(tok::amp) && Right.is(tok::r_square))
       return Style.SpacesInSquareBrackets;
-    return Style.SpaceAfterLogicalNot && Left.is(tok::exclaim);
+    if (Left.isNot(tok::exclaim))
+      return false;
+    if (Left.TokenText == "!")
+      return Style.SpaceAfterLogicalNot;
+    assert(Left.TokenText == "not");
+    return Right.isOneOf(tok::coloncolon, TT_UnaryOperator);
   }
 
   // If the next token is a binary operator or a selector name, we have
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 6508ca2e7174f..44341fbfe895f 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -25067,8 +25067,10 @@ TEST_F(FormatTest, AlternativeOperators) {
   verifyFormat("%:define ABC abc"); // #define ABC abc
   verifyFormat("%:%:");             // ##
 
+  verifyFormat("return not ::f();");
+  verifyFormat("return not *foo;");
+
   verifyFormat("a = v(not;);\n"
-               "b = v(not+);\n"
                "c = v(not x);\n"
                "d = v(not 1);\n"
                "e = v(not 123.f);");
@@ -25076,7 +25078,6 @@ TEST_F(FormatTest, AlternativeOperators) {
   verifyNoChange("#define ASSEMBLER_INSTRUCTION_LIST(V)  \\\n"
                  "  V(and)                               \\\n"
                  "  V(not)                               \\\n"
-                 "  V(not!)                              \\\n"
                  "  V(other)",
                  getLLVMStyleWithColumns(40));
 }