Make test categories composable

Summary:
Previously the add_test_categories would simply overwrite the current set of categories for a
method. This change makes the decorator truly "add" categories, by extending the current set of
categories instead of replacing it.

To do this, I have:
- replaced the getCategories() property on a method (which was itself a method), with a simple
  list property "categories". This makes add_test_categories easier to implement, and test
  categories isn't something which should change between calls anyway.
- rewritten the getCategoriesForTest function to merge method categories with the categories of
  the test case. Previously, it would just use the method categories if they were present. I have
  also greatly simplified this method. Originally, it would use a lot of introspection to enable
  it being called on various types of objects. Based on my tests, it was only ever being called
  on a test case. The new function uses much less introspection then the preivous one, so we
  should easily catch any stray uses, if there are any, as they will generate exceptions now.

Reviewers: zturner, tfiala, tberghammer

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D15451

llvm-svn: 255493

1 files changed, 8 insertions, 2 deletions

diff --git a/lldb/packages/Python/lldbsuite/test/lldbtest.py b/lldb/packages/Python/lldbsuite/test/lldbtest.py
index 77caab5f6f0..7fed0c47eea 100644
--- a/lldb/packages/Python/lldbsuite/test/lldbtest.py
+++ b/lldb/packages/Python/lldbsuite/test/lldbtest.py
@@ -509,12 +509,18 @@ def check_expected_version(comparison, expected, actual):
 # Decorators for categorizing test cases.
 #
 from functools import wraps
+
 def add_test_categories(cat):
-    """Decorate an item with test categories"""
+    """Add test categories to a TestCase method"""
     cat = test_categories.validate(cat, True)
     def impl(func):
-        func.getCategories = lambda test: cat
+        if isinstance(func, type) and issubclass(func, unittest2.TestCase):
+            raise Exception("@add_test_categories can only be used to decorate a test method")
+        if hasattr(func, "categories"):
+            cat.extend(func.categories)
+        func.categories = cat
         return func
+
     return impl
 
 def benchmarks_test(func):