[clang] [clang-format][NFC] Skip ObjCHeaderStyleGuesser for empty code (PR #82957)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang-format

Author: Owen Pan (owenca)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/82957.diff


1 Files Affected:

- (modified) clang/lib/Format/Format.cpp (+1-1) 


``````````diff
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 2f6b52510099a7..00ffc6718e052b 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -3920,7 +3920,7 @@ FormatStyle::LanguageKind guessLanguage(StringRef FileName, StringRef Code) {
     auto Extension = llvm::sys::path::extension(FileName);
     // If there's no file extension (or it's .h), we need to check the contents
     // of the code to see if it contains Objective-C.
-    if (Extension.empty() || Extension == ".h") {
+    if (!Code.empty() && (Extension.empty() || Extension == ".h")) {
       auto NonEmptyFileName = FileName.empty() ? "guess.h" : FileName;
       Environment Env(Code, NonEmptyFileName, /*Ranges=*/{});
       ObjCHeaderStyleGuesser Guesser(Env, getLLVMStyle());

``````````

</details>


https://github.com/llvm/llvm-project/pull/82957