[clang] [clang-format] fix aligning inheritance lists and binary operator operands with UT_AlignWithSpaces (PR #189218)

[Eugene Shalygin via cfe-commits]

https://github.com/zeule updated https://github.com/llvm/llvm-project/pull/189218

>From 09a9401344d974cd38a0fe464fa1e0b78f5aca05 Mon Sep 17 00:00:00 2001
From: Eugene Shalygin <e.shalygin at abberior-instruments.com>
Date: Fri, 27 Mar 2026 17:02:04 +0100
Subject: [PATCH 1/2] [clang-format] fix aligning inheritance lists with
 UT_AlignWithSpaces

---
 clang/lib/Format/ContinuationIndenter.cpp | 19 ++++++++++
 clang/unittests/Format/FormatTest.cpp     | 46 +++++++++++++++++++++++
 2 files changed, 65 insertions(+)

diff --git a/clang/lib/Format/ContinuationIndenter.cpp b/clang/lib/Format/ContinuationIndenter.cpp
index a388b74920e0b..416a947426ccd 100644
--- a/clang/lib/Format/ContinuationIndenter.cpp
+++ b/clang/lib/Format/ContinuationIndenter.cpp
@@ -1238,6 +1238,25 @@ unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State,
     }
   }
 
+  switch (Style.BreakInheritanceList) {
+  case FormatStyle::BILS_BeforeColon:
+  case FormatStyle::BILS_AfterComma:
+    CurrentState.IsAligned = CurrentState.IsAligned ||
+                             Current.is(TT_InheritanceColon) ||
+                             Previous.is(TT_InheritanceComma);
+    break;
+  case FormatStyle::BILS_BeforeComma:
+    CurrentState.IsAligned =
+        CurrentState.IsAligned ||
+        Current.isOneOf(TT_InheritanceColon, TT_InheritanceComma);
+    break;
+  case FormatStyle::BILS_AfterColon:
+    CurrentState.IsAligned =
+        CurrentState.IsAligned ||
+        Previous.isOneOf(TT_InheritanceColon, TT_InheritanceComma);
+    break;
+  }
+
   if ((PreviousNonComment &&
        PreviousNonComment->isOneOf(tok::comma, tok::semi) &&
        !CurrentState.AvoidBinPacking) ||
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index e0b2644249e76..62d7f3b620012 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -8435,6 +8435,52 @@ TEST_F(FormatTest, BreakConstructorInitializersAfterColon) {
       "  : public aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa,\n"
       "    public bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb {};",
       Style);
+
+  FormatStyle Tabbed = getLLVMStyle();
+  Tabbed.IndentWidth = 4;
+  Tabbed.TabWidth = 4;
+  Tabbed.UseTab = FormatStyle::UT_AlignWithSpaces;
+  Tabbed.BreakInheritanceList = FormatStyle::BILS_BeforeColon;
+  verifyFormat(
+      "class BeforeColonTabbed\n"
+      "    : public aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa,\n"
+      "      protected bbbbbbbbbbbbbbbbbb,\n"
+      "      private cccccccccccccccccccccc,\n"
+      "      dddddddddd {};",
+      Tabbed);
+  Tabbed.BreakInheritanceList = FormatStyle::BILS_BeforeComma;
+  verifyFormat(
+      "class BeforeCommaTabbed\n"
+      "    : public aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\n"
+      "    , protected bbbbbbbbb\n"
+      "    , private cccccccccc\n"
+      "    , dddddddddd {};",
+      Tabbed);
+  Tabbed.BreakInheritanceList = FormatStyle::BILS_AfterColon;
+  verifyFormat(
+      "class AfterColonTabbed :\n"
+      "    public aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa,\n"
+      "    protected bbbbbbbbb,\n"
+      "    private cccccccccc,\n"
+      "    dddddddddd {};",
+      Tabbed);
+  Tabbed.BreakInheritanceList = FormatStyle::BILS_AfterComma;
+  verifyFormat("class AfterCommaTabbed : public aaaaaaaaa,\n"
+               "                         protected bbbbbbbbb,\n"
+               "                         private cccccccccc,\n"
+               "                         ddddddddd {};",
+               Tabbed);
+  verifyFormat(
+      "class SomeClass\n"
+      "    : public aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa,\n"
+      "      public bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb {};",
+      Tabbed);
+  Tabbed.ColumnLimit = 42;
+  verifyFormat("struct S {\n"
+               "\tclass Foo : public aaaaaaaaa,\n"
+               "\t            private bbbbbbbbb {};\n"
+               "};",
+               Tabbed);
 }
 
 TEST_F(FormatTest, BreakConstructorInitializersAfterComma) {

>From 7aed9d9b07db7c0e72de413d4b51a9535255956d Mon Sep 17 00:00:00 2001
From: Eugene Shalygin <eugene.shalygin at gmail.com>
Date: Sun, 29 Mar 2026 22:12:46 +0200
Subject: [PATCH 2/2] [clang-format] fix aligning binary operator operands

Mark operators of binary operators as aligned.
---
 clang/lib/Format/ContinuationIndenter.cpp |  4 +++-
 clang/unittests/Format/FormatTest.cpp     | 13 +++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/clang/lib/Format/ContinuationIndenter.cpp b/clang/lib/Format/ContinuationIndenter.cpp
index 416a947426ccd..fc5e1000ad750 100644
--- a/clang/lib/Format/ContinuationIndenter.cpp
+++ b/clang/lib/Format/ContinuationIndenter.cpp
@@ -1273,8 +1273,10 @@ unsigned ContinuationIndenter::addTokenOnNewLine(LineState &State,
       (PreviousNonComment && PreviousNonComment->is(tok::question))) {
     CurrentState.BreakBeforeParameter = true;
   }
-  if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore)
+  if (Current.is(TT_BinaryOperator) && Current.CanBreakBefore) {
     CurrentState.BreakBeforeParameter = false;
+    CurrentState.IsAligned = true;
+  }
 
   if (!DryRun) {
     unsigned MaxEmptyLinesToKeep = Style.MaxEmptyLinesToKeep + 1;
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 62d7f3b620012..bd17663c900fa 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -17073,6 +17073,19 @@ TEST_F(FormatTest, ConfigurableUseOfTab) {
                "\t}\n"
                "};",
                Tab);
+  verifyFormat("aStreamObject << aaaaaaaaaaaaa\n"
+               "              << bbbbbbbbb;\n",
+               Tab);
+  verifyFormat("result = aaaaaaaaaaaaaaaaaaaaaaaa +\n"
+               "         bbbbbbbbbbbbbbbbbbbb;",
+               Tab);
+  verifyFormat("class C {\n"
+               "\tvoid foo() {\n"
+               "\t\taStreamObject << aaaaaaaaaaaaa\n"
+               "\t\t              << bbbbbbbbb;\n"
+               "\t}\n"
+               "};",
+               Tab);
   Tab.TabWidth = 8;
   Tab.IndentWidth = 4;
   verifyFormat("class TabWidth8Indent4 {\n"