[clang-tools-extra] [clang-tidy] Return error code on config parse error (PR #136167)

[Galen Elias via cfe-commits]

================
@@ -46,20 +46,20 @@ TEST(ClangTidyOptionsProvider, InMemoryFileSystems) {
 
   FileOptionsProvider FileOpt({}, {}, {}, FileSystem);
 
-  ClangTidyOptions File1Options =
+  llvm::ErrorOr<ClangTidyOptions> File1Options =
       FileOpt.getOptions("ProjectRoot/SubDir1/File.cpp");
-  ClangTidyOptions File2Options =
+  llvm::ErrorOr<ClangTidyOptions> File2Options =
       FileOpt.getOptions("ProjectRoot/SubDir1/SubDir2/File.cpp");
-  ClangTidyOptions File3Options =
+  llvm::ErrorOr<ClangTidyOptions> File3Options =
       FileOpt.getOptions("ProjectRoot/SubDir1/SubDir2/SubDir3/File.cpp");
 
-  ASSERT_TRUE(File1Options.Checks.has_value());
-  EXPECT_EQ(*File1Options.Checks, "-*,clang-diagnostic-*,readability-*");
-  ASSERT_TRUE(File2Options.Checks.has_value());
-  EXPECT_EQ(*File2Options.Checks, "bugprone-*,misc-*,clang-diagnostic-*");
+  ASSERT_TRUE(File1Options->Checks.has_value());
+  EXPECT_EQ(*File1Options->Checks, "-*,clang-diagnostic-*,readability-*");
+  ASSERT_TRUE(File2Options->Checks.has_value());
+  EXPECT_EQ(*File2Options->Checks, "bugprone-*,misc-*,clang-diagnostic-*");
 
   // 2 and 3 should use the same config so these should also be the same.
-  EXPECT_EQ(File2Options.Checks, File3Options.Checks);
+  EXPECT_EQ(File2Options->Checks, File3Options->Checks);
 }
----------------
galenelias wrote:

I couldn't find any tests which exercise `clangTidyMain` (which makes sense, as that is not really the layer a unit test would operate on.  The best place I could find to put a test was near the ClangTidyOptionsProvider.InMemoryFileSystems test, which at least tests the behavior with multiple configuration files, as well as some amount of the propagation logic.

I will go ahead and add a test there unless there is a more appropriate spot for verifying the high level "early exit code 1" behavior of the PR.

https://github.com/llvm/llvm-project/pull/136167