[lldb] Fix debug_info decorators for NO_DEBUG_INFO_TESTCASE

[JDevlieghere]

Summary

Currently a NO_DEBUG_INFO_TESTCASE will return None as it's debug info
type, causing the decorator to consider it a match. If such a test case
is marked as an expected failure, the decorator will incorrectly cause
an XPASS.

I discovered this issue when I was trying to speed up our remote test
suite by running every test as a single variant.

[mib]

Good catch! LGTM!

[labath]

I think this is actually a wider problem. I also ran into this recently (with triples), but didn't have time to create a patch yet. I don't think that None as the "actual" value should ever be considered a match (except when the pattern is None, I guess), regardless of whether it is a debug info variant, triple, or anything else. (None as a "pattern" should of course continue to match anything.)

[JDevlieghere]

In D123401#3439560, @labath wrote:

I think this is actually a wider problem. I also ran into this recently (with triples), but didn't have time to create a patch yet. I don't think that None as the "actual" value should ever be considered a match (except when the pattern is None, I guess), regardless of whether it is a debug info variant, triple, or anything else. (None as a "pattern" should of course continue to match anything.)

Agreed. I tried that but that caused a bunch of test failures. It's probably worth investigating, but my current focus is addressing some issues with our on-device test suite.

[labath]

Thanks.

lldb/packages/Python/lldbsuite/test/decorators.py

def _check_expected_version(comparison, expected, actual):
 
     return op_lookup[comparison](
         LooseVersion(actual_str),
         LooseVersion(expected_str))
 
 
 _re_pattern_type = type(re.compile(''))
 def _match_decorator_property(expected, actual):
-    if actual is None or expected is None:
+    if expected is None:
         return True
 
+    if actual is None :
+        return False
+
     if isinstance(expected, no_match):
         return not _match_decorator_property(expected.item, actual)
-    elif isinstance(expected, (_re_pattern_type,) + six.string_types):
+
+    if isinstance(expected, (_re_pattern_type,) + six.string_types):
         return re.search(expected, actual) is not None
-    elif hasattr(expected, "__iter__"):
+
+    if hasattr(expected, "__iter__"):
         return any([x is not None and _match_decorator_property(x, actual)
                     for x in expected])
-    else:
-        return expected == actual
+
 
 
 def _compiler_supports(compiler,
                        flag,
                        source='int main() {}',
                        output_file=tempfile.NamedTemporaryFile()):
     """Test whether the compiler supports the given flag."""
     if platform.system() == 'Darwin':

lldb/test/API/test_utils/TestDecorators.py

+from lldbsuite.test.lldbtest import Base
+from lldbsuite.test.decorators import *
+
+
+class TestDecorators(Base):
+
+    mydir = Base.compute_mydir(__file__)
+    NO_DEBUG_INFO_TESTCASE = True
+
+    @expectedFailureAll(debug_info="dwarf")
+    def test_decorator_skip_no_debug_info(self):
+        """Test that specifying a debug info category works for a NO_DEBUG_INFO_TESTCASE"""
+        pass