[clang] [clang-format] Fix a regression in ContinuationIndenter (PR #88414)

[Owen Pan via cfe-commits]

https://github.com/owenca created https://github.com/llvm/llvm-project/pull/88414

Commit d06b92391513 caused a regression that breaks after a block comment adjacent to a function paramter that follows.

Fixes #86573.

>From 2ec43f6dc1fafed9d7fc324eeacfa07133af3abd Mon Sep 17 00:00:00 2001
From: Owen Pan <owenpiano at gmail.com>
Date: Thu, 11 Apr 2024 09:40:01 -0700
Subject: [PATCH] [clang-format] Fix a regression in ContinuationIndenter

Commit d06b92391513 caused a regression that breaks after a block comment
adjacent to a function paramter that follows.

Fixes #86573.
---
 clang/lib/Format/ContinuationIndenter.cpp     | 8 +++++++-
 clang/unittests/Format/FormatTestComments.cpp | 4 ++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/clang/lib/Format/ContinuationIndenter.cpp b/clang/lib/Format/ContinuationIndenter.cpp
index 700bce35c86839..ad0e2c3c620c32 100644
--- a/clang/lib/Format/ContinuationIndenter.cpp
+++ b/clang/lib/Format/ContinuationIndenter.cpp
@@ -684,7 +684,13 @@ void ContinuationIndenter::addTokenOnCurrentLine(LineState &State, bool DryRun,
         // arguments to function calls. We do this by ensuring that either all
         // arguments (including any lambdas) go on the same line as the function
         // call, or we break before the first argument.
-        auto PrevNonComment = Current.getPreviousNonComment();
+        const auto *Prev = Current.Previous;
+        if (!Prev)
+          return false;
+        // For example, `/*Newline=*/false`.
+        if (Prev->is(TT_BlockComment) && Current.SpacesRequiredBefore == 0)
+          return false;
+        const auto *PrevNonComment = Current.getPreviousNonComment();
         if (!PrevNonComment || PrevNonComment->isNot(tok::l_paren))
           return false;
         if (Current.isOneOf(tok::comment, tok::l_paren, TT_LambdaLSquare))
diff --git a/clang/unittests/Format/FormatTestComments.cpp b/clang/unittests/Format/FormatTestComments.cpp
index d705cf34d8af02..d2baace6a7d809 100644
--- a/clang/unittests/Format/FormatTestComments.cpp
+++ b/clang/unittests/Format/FormatTestComments.cpp
@@ -376,6 +376,10 @@ TEST_F(FormatTestComments, RemovesTrailingWhitespaceOfComments) {
 TEST_F(FormatTestComments, UnderstandsBlockComments) {
   verifyFormat("f(/*noSpaceAfterParameterNamingComment=*/true);");
   verifyFormat("void f() { g(/*aaa=*/x, /*bbb=*/!y, /*c=*/::c); }");
+  verifyFormat("fooooooooooooooooooooooooooooo(\n"
+               "    /*qq_=*/move(q), [this, b](bar<void(uint32_t)> b) {},\n"
+               "    c);",
+               getLLVMStyleWithColumns(60));
   EXPECT_EQ("f(aaaaaaaaaaaaaaaaaaaaaaaaa, /* Trailing comment for aa... */\n"
             "  bbbbbbbbbbbbbbbbbbbbbbbbb);",
             format("f(aaaaaaaaaaaaaaaaaaaaaaaaa ,   \\\n"