[clang] [clang-format] Fix missing indentation for assignment with attributes (PR #230417)

[Priyanshu Ranjan via cfe-commits]

https://github.com/priyanshujaiz updated https://github.com/llvm/llvm-project/pull/230417

>From 480dca9c02b7ac212a074eab91cd9de5aa716274 Mon Sep 17 00:00:00 2001
From: Priyanshu Jaiz <pj041132 at example.com>
Date: Fri, 9 Oct 2026 09:02:04 +0000
Subject: [PATCH] [clang-format] Fix missing indentation for assignment with
 attributes Fixes #229206. When `BreakBeforeBinaryOperators: All` is
 configured, formatting a variable definition with an attribute (e.g.
 `[[maybe_unused]]`) between the variable name and the assignment previously
 caused the assignment operator to lose all continuation indentation (starting
 at column 0). The root cause was in
 `ContinuationIndenter::getNewLineColumn()`. The logic assumed that any token
 following an attribute closing bracket (`TT_AttributeRSquare`) should not be
 indented as a continuation. It failed to account for binary operators (like
 `=`) which are valid continuations of the variable declaration statement. A
 regression test has been added to
 `FormatTest.BreakBinaryOperatorsInPresenceOfTemplates` to verify the 4-space
 continuation indent is correctly applied when formatting wraps at the column
 limit. Assisted-by: Antigravity AI

---
 clang/lib/Format/ContinuationIndenter.cpp | 5 +++--
 clang/unittests/Format/FormatTest.cpp     | 9 +++++++++
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/clang/lib/Format/ContinuationIndenter.cpp b/clang/lib/Format/ContinuationIndenter.cpp
index bb8179cbc4f95f..636ab7d24ee316 100644
--- a/clang/lib/Format/ContinuationIndenter.cpp
+++ b/clang/lib/Format/ContinuationIndenter.cpp
@@ -1692,10 +1692,11 @@ ContinuationIndenter::getNewLineColumn(const LineState &State) {
          Current.isNot(tok::l_paren) &&
          !Current.endsSequence(TT_StartOfName, TT_AttributeMacro,
                                TT_PointerOrReference)) ||
-        PreviousNonComment->isOneOf(TT_AttributeRParen, TT_AttributeRSquare,
+        (PreviousNonComment->isOneOf(TT_AttributeRParen, TT_AttributeRSquare,
                                     TT_FunctionAnnotationRParen,
                                     TT_JavaAnnotation,
-                                    TT_LeadingJavaAnnotation))) ||
+                                    TT_LeadingJavaAnnotation) &&
+         !Current.isBinaryOperator()))) ||
       (!Style.IndentWrappedFunctionNames &&
        NextNonComment->isOneOf(tok::kw_operator, TT_FunctionDeclarationName)) ||
       (State.Line->ReturnTypeWrapped && PreviousNonComment &&
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index d346036448140c..c77a0db87d31b6 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -7790,6 +7790,15 @@ TEST_F(FormatTest, BreakBinaryOperatorsInPresenceOfTemplates) {
                "         and is_swappable_v<hash<T>>\n"
                "         and is_callable_v<hash<T>(T)>;",
                Style);
+
+  FormatStyle Style80 = getLLVMStyle();
+  Style80.BreakBeforeBinaryOperators = FormatStyle::BOS_All;
+  verifyFormat("static constexpr long long variable_with_long_name_without_attribute\n"
+               "    = 1234567890;\n"
+               "static constexpr long long long_variable_with_attribute "
+               "[[maybe_unused]]\n"
+               "    = 9876543210;",
+               Style80);
 }
 
 TEST_F(FormatTest, ConstructorInitializers) {