[lldb] Make log for ClangModulesDeclVendor's compiler flag less verbose

[teemperor]

Summary

Currently the ClangModulesDeclVendor is spamming the expression log with the compiler flags it is using, which creates a log that looks like this:

clang


 -fmodules


 -fimplicit-module-maps

This patch removes all these newlines and just prints the compiler flags in one line as you see in the command line:

clang -fmodules -fimplicit-module-maps [...]

[davide]

This looks good. If it bothers you a lot (given you're probably one of the few users), you can do this only under verbose (although now that's a single line is very concise).

[shafik]

Is it worth it to write a test that verifies the output? Otherwise LGTM.

[davide]

I don't think it's worth adding a test for the logs.

lldb/source/Plugins/ExpressionParser/Clang/ClangModulesDeclVendor.cpp

if (FileSystem::Instance().IsDirectory(clang_resource_dir.GetPath())) {
       compiler_invocation_arguments.push_back(clang_resource_dir.GetPath());
     }
   }
 
   llvm::IntrusiveRefCntPtr<clang::DiagnosticsEngine> diagnostics_engine =
       clang::CompilerInstance::createDiagnostics(new clang::DiagnosticOptions,
                                                  new StoringDiagnosticConsumer);
 
-  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
-  if (log)
-    log->PutString("ClangModulesDeclVendor::Create()");
   std::vector<const char *> compiler_invocation_argument_cstrs;
   compiler_invocation_argument_cstrs.reserve(
       compiler_invocation_arguments.size());
-  for (const std::string &arg : compiler_invocation_arguments) {
+  for (const std::string &arg : compiler_invocation_arguments)
     compiler_invocation_argument_cstrs.push_back(arg.c_str());
-    if (log) {
-      log->PutString("\n  ");
-      log->PutString(arg);
-    }
-  }
-  if (log)
-    log->PutString("\n");
+
+  Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS));
+  LLDB_LOG(log, "ClangModulesDeclVendor's compiler flags {0:$[ ]}",
+           llvm::make_range(compiler_invocation_arguments.begin(),
+                            compiler_invocation_arguments.end()));
 
   std::shared_ptr<clang::CompilerInvocation> invocation =
       clang::createInvocationFromCommandLine(compiler_invocation_argument_cstrs,
                                              diagnostics_engine);
 
   if (!invocation)
     return nullptr;