[clang-tools-extra] Clang doc async (PR #93276)

[Paul Kirth via cfe-commits]

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@@ -1049,31 +1047,33 @@ static llvm::Error CopyFile(StringRef FilePath, StringRef OutDirectory) {
   std::error_code FileErr = llvm::sys::fs::copy_file(PathRead, PathWrite);
   if (FileErr != OK) {
     return llvm::createStringError(llvm::inconvertibleErrorCode(),
-                                   "error creating file " +
-                                       llvm::sys::path::filename(FilePath) +
-                                       ": " + FileErr.message() + "\n");
+                                   "error creating file " + FilePath + ": " +
+                                       FileErr.message() + "\n");
   }
   return llvm::Error::success();
 }
 
 llvm::Error HTMLGenerator::createResources(ClangDocContext &CDCtx) {
-  auto Err = SerializeIndex(CDCtx);
-  if (Err)
+  if (auto Err = SerializeIndex(CDCtx)) {
     return Err;
-  Err = GenIndex(CDCtx);
-  if (Err)
+  }
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ilovepi wrote:

I'm not sure updating the error handling here and below is a functional improvement. However, even if it is, it belongs in a separate PR, as its unrelated to the work done in this patch. While we normally don't use `auto` that much in llvm (see https://llvm.org/docs/CodingStandards.html#use-auto-type-deduction-to-make-code-more-readable), an error code is probably an OK time to use one. Unfortunately, these APIs don't seem to obviously return an error based on their signatures, so you may want to consider using an explicit type (but its not required). Lastly, our style guide only uses braces for conditionals w/ multiple lines (see https://llvm.org/docs/CodingStandards.html#don-t-use-braces-on-simple-single-statement-bodies-of-if-else-loop-statements). 

https://github.com/llvm/llvm-project/pull/93276