[clang] [clang-format] Fix InsertBraces inserting braces around directives (PR #224947)

[Andre Sun via cfe-commits]

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@@ -2910,22 +2910,39 @@ void UnwrappedLineParser::parseUnbracedBody(bool CheckEOF) {
   }
 
   addUnwrappedLine();
+  const size_t BodyStart = CurrentLines->size();
   ++Line->Level;
   ++Line->UnbracedBodyLevel;
   parseStructuralElement();
   --Line->UnbracedBodyLevel;
 
   if (Tok) {
     assert(!Line->InPPDirective);
+    FormatToken *const LBraceTok = Tok;
     Tok = nullptr;
-    for (const auto &L : llvm::reverse(*CurrentLines)) {
+    size_t BodyEnd = CurrentLines->size();
+    while (BodyEnd > 0) {
+      const auto &L = (*CurrentLines)[--BodyEnd];
       if (!L.InPPDirective && getLastNonComment(L)) {
         Tok = L.Tokens.back().Tok;
         break;
       }
     }
     assert(Tok);
-    ++Tok->BraceCount;
+    // Don't insert the braces if they would enclose preprocessor directives.
+    bool EnclosesPPDirective = false;
+    for (size_t I = BodyStart; I <= BodyEnd && !EnclosesPPDirective; ++I) {
+      const auto &L = (*CurrentLines)[I];
+      EnclosesPPDirective =
+          L.InPPDirective ||
+          llvm::any_of(L.Tokens, [](const UnwrappedLineNode &Node) {
----------------
and2049 wrote:

`FirstAfterPPLine` can also apply to the token after a directive in the middle of an unwrapped line, such as on `1` in `f(\n#ifdef A\n 1);` in the new nested while/if test case.

I tried with checking only the first token, which makes that test fail.

https://github.com/llvm/llvm-project/pull/224947