[lit] Fix unit test discovery for Visual Studio builds.

[andrewng]

Summary

The Visual Studio build can contain output for multiple configuration types (
e.g. Debug, Release & RelWithDebInfo) within the same build output
directory. Therefore when discovering unit tests, the "build mode" sub directory
containing the appropriate configuration is included in the search. This sub
directory may not always be present, so a test for its existence is required.

[grimar]

I can confirm that fixes issue I mentioned in comments for D34855. thanks !

[andrewng]

Hi,

This patch fixes a Windows Visual Studio build lit issue introduced by rL306895 (D34855).

Cheers,
Andrew

[andrewng]

Is this patch good to land?

Cheers,
Andrew

[dlj]

Sorry for the delay, and do apologize for the breakage.

llvm/trunk/utils/lit/lit/formats/googletest.py

def getGTestTests(self, path, litConfig, localConfig):
                 continue
             else:
                 yield ''.join(nested_tests) + ln
 
     def getTestsInDirectory(self, testSuite, path_in_suite,
                             litConfig, localConfig):
         source_path = testSuite.getSourcePath(path_in_suite)
         for subdir in self.test_sub_dirs:
-            for fn in lit.util.listdir_files(os.path.join(source_path, subdir),
+            dir_path = os.path.join(source_path, subdir)
+            if not os.path.isdir(dir_path):
+                continue
+            for fn in lit.util.listdir_files(dir_path,
                                              suffixes={self.test_suffix}):
                 # Discover the tests in this executable.
                 execpath = os.path.join(source_path, subdir, fn)
                 testnames = self.getGTestTests(execpath, litConfig, localConfig)
                 for testname in testnames:
                     testPath = path_in_suite + (subdir, fn, testname)
                     yield lit.Test.Test(testSuite, testPath, localConfig,
                                         file_path=execpath)