1 files changed, 48 insertions, 0 deletions
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index f225c1a30c1..f5e7a206a56 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -1765,6 +1765,15 @@ public:
 
     checkEmptyNamespace(AnnotatedLines);
 
+    for (auto &Line : AnnotatedLines) {
+      if (Line->Affected) {
+        cleanupRight(Line->First, tok::comma, tok::comma);
+        cleanupRight(Line->First, TT_CtorInitializerColon, tok::comma);
+        cleanupLeft(Line->First, TT_CtorInitializerComma, tok::l_brace);
+        cleanupLeft(Line->First, TT_CtorInitializerColon, tok::l_brace);
+      }
+    }
+
     return generateFixes();
   }
 
@@ -1853,6 +1862,45 @@ private:
     return true;
   }
 
+  // Checks pairs {start, start->next},..., {end->previous, end} and deletes one
+  // of the token in the pair if the left token has \p LK token kind and the
+  // right token has \p RK token kind. If \p DeleteLeft is true, the left token
+  // is deleted on match; otherwise, the right token is deleted.
+  template <typename LeftKind, typename RightKind>
+  void cleanupPair(FormatToken *Start, LeftKind LK, RightKind RK,
+                   bool DeleteLeft) {
+    auto NextNotDeleted = [this](const FormatToken &Tok) -> FormatToken * {
+      for (auto *Res = Tok.Next; Res; Res = Res->Next)
+        if (!Res->is(tok::comment) &&
+            DeletedTokens.find(Res) == DeletedTokens.end())
+          return Res;
+      return nullptr;
+    };
+    for (auto *Left = Start; Left;) {
+      auto *Right = NextNotDeleted(*Left);
+      if (!Right)
+        break;
+      if (Left->is(LK) && Right->is(RK)) {
+        deleteToken(DeleteLeft ? Left : Right);
+        // If the right token is deleted, we should keep the left token
+        // unchanged and pair it with the new right token.
+        if (!DeleteLeft)
+          continue;
+      }
+      Left = Right;
+    }
+  }
+
+  template <typename LeftKind, typename RightKind>
+  void cleanupLeft(FormatToken *Start, LeftKind LK, RightKind RK) {
+    cleanupPair(Start, LK, RK, /*DeleteLeft=*/true);
+  }
+
+  template <typename LeftKind, typename RightKind>
+  void cleanupRight(FormatToken *Start, LeftKind LK, RightKind RK) {
+    cleanupPair(Start, LK, RK, /*DeleteLeft=*/false);
+  }
+
   // Delete the given token.
   inline void deleteToken(FormatToken *Tok) {
     if (Tok)