Initial attempt to support return statements in try-finally block in llpython.byte_control. Added incomplete unit tests.

llpython/tests/test_byte_control.py

@@ -0,0 +1,81 @@
+#! /usr/bin/env python
+# ______________________________________________________________________
+
+from __future__ import absolute_import
+
+import unittest
+
+from llpython import byte_control
+
+# ______________________________________________________________________
+# Global data
+
+got_done = 0
+
+# ______________________________________________________________________
+# Utility function definitions
+
+def do_something():
+    global got_done
+    got_done += 1
+    print("Something good got done.")
+
+# ____________________________________________________________
+
+def do_something_else():
+    raise Exception("Something bad got done, and I don't like it")
+
+# ______________________________________________________________________
+# Test function definitions
+
+def try_finally_0(m, n): # why == WHY_RETURN
+    try:
+        return n - m
+    finally:
+        do_something()
+    return do_something_else()
+
+# ____________________________________________________________
+
+def try_finally_1(m, n): # why == WHY_BREAK
+    i = -1
+    for i in range(m, n):
+        try:
+            if i == 101:
+                break
+        finally:
+            do_something()
+    return i
+
+# ______________________________________________________________________
+# Class (test case) definition(s)
+
+class TestByteControl(unittest.TestCase):
+    def fail_unless_cfg_match(self, test_cfg, block_count, edges):
+        assert len(test_cfg.blocks) == block_count
+        block_keys = list(test_cfg.blocks.keys())
+        block_keys.sort()
+        # TODO: Ensure unexpected edges cause error.
+        for from_block_ofs, to_block_ofs in edges:
+            from_block = block_keys[from_block_ofs]
+            to_block = block_keys[to_block_ofs]
+            assert from_block in test_cfg.blocks_in[to_block]
+            assert to_block in test_cfg.blocks_out[from_block]
+
+    def test_try_finally_0(self):
+        cfg = byte_control.build_cfg(try_finally_0)
+        self.fail_unless_cfg_match(cfg, 5, ((0, 1), (0, 3), (1, 3), (2, 3),
+                                            (3, 4)))
+
+    def test_try_finally_1(self):
+        cfg = byte_control.build_cfg(try_finally_1)
+        # TODO: Translate known graph to offsets...
+        self.fail_unless_cfg_match(cfg, 12, ())
+
+# ______________________________________________________________________
+
+if __name__ == "__main__":
+    unittest.main()
+
+# ______________________________________________________________________
+# End of test_byte_control.py