Python: Add more tests for MaD sources

python/ql/test/library-tests/frameworks/data/test.ext.yml

@@ -23,6 +23,12 @@ extensions:
       - ["testlib", "Member[ArgPos].Member[MyClass].Subclass.Member[otherSelfTest].Parameter[0]", "test-source"]
       - ["testlib", "Member[ArgPos].Member[MyClass].Subclass.Member[anyParam].Parameter[any]", "test-source"]
       - ["testlib", "Member[ArgPos].Member[MyClass].Subclass.Member[anyNamed].Parameter[any-named]", "test-source"]
+      # test steps through content
+      - ["testlib", "Member[source_dict].DictionaryElement[key].Member[func].ReturnValue", "test-source"]
+      - ["testlib", "Member[source_dict_any].DictionaryElementAny.Member[func].ReturnValue", "test-source"]
+      # TODO: Add support for list/tuples
+      # - ["testlib", "Member[source_list].ListElement.Member[func].ReturnValue", "test-source"]
+      # - ["testlib", "Member[source_tuple].TupleElement[0].Member[func].ReturnValue", "test-source"]
 
   - addsTo:
       pack: codeql/python-all

python/ql/test/library-tests/frameworks/data/test.py

@@ -117,3 +117,17 @@ testlib.foo.bar.baz.fuzzyCall(getSource()) # NOT OK
 testlib.foo().bar().fuzzyCall(getSource()) # NOT OK
 testlib.foo(lambda x: x.fuzzyCall(getSource())) # NOT OK
 otherlib.fuzzyCall(getSource()) # OK
+
+# defining sources through content steps
+
+# dictionaries
+testlib.source_dict["key"].func() # source
+testlib.source_dict["safe"].func() # not a source
+lambda k: testlib.source_dict_any[k].func() # source
+
+# TODO: implement support for lists
+lambda i: testlib.source_list[i].func()
+
+# TODO: implement support for tuples
+testlib.source_tuple[0].func() # a source
+testlib.source_tuple[1].func() # not a source