Python: more tests and comments

python/ql/test/experimental/dataflow/module-initialization/multiphase.py

@@ -0,0 +1,43 @@
+import sys
+import os
+
+sys.path.append(os.path.dirname(os.path.dirname((__file__))))
+from testlib import *
+
+# These are defined so that we can evaluate the test code.
+NONSOURCE = "not a source"
+SOURCE = "source"
+
+
+def is_source(x):
+    return x == "source" or x == b"source" or x == 42 or x == 42.0 or x == 42j
+
+
+def SINK(x):
+    if is_source(x):
+        print("OK")
+    else:
+        print("Unexpected flow", x)
+
+
+def SINK_F(x):
+    if is_source(x):
+        print("Unexpected flow", x)
+    else:
+        print("OK")
+
+def set_foo():
+    global foo
+    print(foo)
+    foo = SOURCE
+
+foo = NONSOURCE
+set_foo()
+
+@expects(2)
+def test_phases():
+    global foo
+    SINK(foo)
+    foo = NONSOURCE
+    set_foo()
+    SINK(foo)