[NFC][lit] discovery: find_tests_for_inputs: avoid py warning when no suites found

If lit was run on a directory that contained no suites,
then naturally suite[0] will not be there,
and that line would cause python warnings.

So just predicate it with a check that it is there in the first place.

diff --git a/llvm/utils/lit/lit/discovery.py b/llvm/utils/lit/lit/discovery.py
index 43481d8..22d6d85 100644 (file)
--- a/llvm/utils/lit/lit/discovery.py
+++ b/llvm/utils/lit/lit/discovery.py
@@ -284,7 +284,8 @@ def find_tests_for_inputs(lit_config, inputs, indirectlyRunCheck):
     # This data is no longer needed but keeping it around causes awful
     # performance problems while the test suites run.
     for k, suite in test_suite_cache.items():
-      suite[0].test_times = None
+      if suite[0]:
+        suite[0].test_times = None
 
     # If there were any errors during test discovery, exit now.
     if lit_config.numErrors: