[clang-format] Align trailing comments for function parameters

clang/lib/Format/WhitespaceManager.cpp

@@ -399,6 +399,15 @@ AlignTokenSequence(const FormatStyle &Style, unsigned Start, unsigned End,
       }
     }
   }
+
+  // The scope to be aligned may not occupy entire lines. The rest of the line
+  // needs some book-keeping.
+  for (unsigned i = End; i < Changes.size() && Changes[i].NewlinesBefore == 0;
+       ++i) {
+    Changes[i].StartOfTokenColumn += Shift;
+    if (i + 1 != Changes.size())
+      Changes[i + 1].PreviousEndOfTokenColumn += Shift;
+  }
 }
 
 // Walk through a subset of the changes, starting at StartAt, and find

clang/unittests/Format/FormatTest.cpp

@@ -19828,6 +19828,14 @@ TEST_F(FormatTest, AlignConsecutiveDeclarations) {
                "  Test &operator=(const Test &) = default;\n"
                "};",
                Alignment);
+
+  // The comment to the right should still align right.
+  verifyFormat("void foo(int   name, // name\n"
+               "         float name, // name\n"
+               "         int   name) // name\n"
+               "{}",
+               Alignment);
+
   unsigned OldColumnLimit = Alignment.ColumnLimit;
   // We need to set ColumnLimit to zero, in order to stress nested alignments,
   // otherwise the function parameters will be re-flowed onto a single line.