Python code coverage for Lib/test/test_raise.py

#	count	content
1	n/a	# Copyright 2007 Google, Inc. All Rights Reserved.
2	n/a	# Licensed to PSF under a Contributor Agreement.
3	n/a
4	n/a	"""Tests for the raise statement."""
5	n/a
6	n/a	from test import support
7	n/a	import sys
8	n/a	import types
9	n/a	import unittest
10	n/a
11	n/a
12	n/a	def get_tb():
13	n/a	try:
14	n/a	raise OSError()
15	n/a	except:
16	n/a	return sys.exc_info()[2]
17	n/a
18	n/a
19	n/a	class Context:
20	n/a	def __enter__(self):
21	n/a	return self
22	n/a	def __exit__(self, exc_type, exc_value, exc_tb):
23	n/a	return True
24	n/a
25	n/a
26	n/a	class TestRaise(unittest.TestCase):
27	n/a	def test_invalid_reraise(self):
28	n/a	try:
29	n/a	raise
30	n/a	except RuntimeError as e:
31	n/a	self.assertIn("No active exception", str(e))
32	n/a	else:
33	n/a	self.fail("No exception raised")
34	n/a
35	n/a	def test_reraise(self):
36	n/a	try:
37	n/a	try:
38	n/a	raise IndexError()
39	n/a	except IndexError as e:
40	n/a	exc1 = e
41	n/a	raise
42	n/a	except IndexError as exc2:
43	n/a	self.assertTrue(exc1 is exc2)
44	n/a	else:
45	n/a	self.fail("No exception raised")
46	n/a
47	n/a	def test_except_reraise(self):
48	n/a	def reraise():
49	n/a	try:
50	n/a	raise TypeError("foo")
51	n/a	except:
52	n/a	try:
53	n/a	raise KeyError("caught")
54	n/a	except KeyError:
55	n/a	pass
56	n/a	raise
57	n/a	self.assertRaises(TypeError, reraise)
58	n/a
59	n/a	def test_finally_reraise(self):
60	n/a	def reraise():
61	n/a	try:
62	n/a	raise TypeError("foo")
63	n/a	except:
64	n/a	try:
65	n/a	raise KeyError("caught")
66	n/a	finally:
67	n/a	raise
68	n/a	self.assertRaises(KeyError, reraise)
69	n/a
70	n/a	def test_nested_reraise(self):
71	n/a	def nested_reraise():
72	n/a	raise
73	n/a	def reraise():
74	n/a	try:
75	n/a	raise TypeError("foo")
76	n/a	except:
77	n/a	nested_reraise()
78	n/a	self.assertRaises(TypeError, reraise)
79	n/a
80	n/a	def test_raise_from_None(self):
81	n/a	try:
82	n/a	try:
83	n/a	raise TypeError("foo")
84	n/a	except:
85	n/a	raise ValueError() from None
86	n/a	except ValueError as e:
87	n/a	self.assertTrue(isinstance(e.__context__, TypeError))
88	n/a	self.assertIsNone(e.__cause__)
89	n/a
90	n/a	def test_with_reraise1(self):
91	n/a	def reraise():
92	n/a	try:
93	n/a	raise TypeError("foo")
94	n/a	except:
95	n/a	with Context():
96	n/a	pass
97	n/a	raise
98	n/a	self.assertRaises(TypeError, reraise)
99	n/a
100	n/a	def test_with_reraise2(self):
101	n/a	def reraise():
102	n/a	try:
103	n/a	raise TypeError("foo")
104	n/a	except:
105	n/a	with Context():
106	n/a	raise KeyError("caught")
107	n/a	raise
108	n/a	self.assertRaises(TypeError, reraise)
109	n/a
110	n/a	def test_yield_reraise(self):
111	n/a	def reraise():
112	n/a	try:
113	n/a	raise TypeError("foo")
114	n/a	except:
115	n/a	yield 1
116	n/a	raise
117	n/a	g = reraise()
118	n/a	next(g)
119	n/a	self.assertRaises(TypeError, lambda: next(g))
120	n/a	self.assertRaises(StopIteration, lambda: next(g))
121	n/a
122	n/a	def test_erroneous_exception(self):
123	n/a	class MyException(Exception):
124	n/a	def __init__(self):
125	n/a	raise RuntimeError()
126	n/a
127	n/a	try:
128	n/a	raise MyException
129	n/a	except RuntimeError:
130	n/a	pass
131	n/a	else:
132	n/a	self.fail("No exception raised")
133	n/a
134	n/a	def test_new_returns_invalid_instance(self):
135	n/a	# See issue #11627.
136	n/a	class MyException(Exception):
137	n/a	def __new__(cls, *args):
138	n/a	return object()
139	n/a
140	n/a	with self.assertRaises(TypeError):
141	n/a	raise MyException
142	n/a
143	n/a	def test_assert_with_tuple_arg(self):
144	n/a	try:
145	n/a	assert False, (3,)
146	n/a	except AssertionError as e:
147	n/a	self.assertEqual(str(e), "(3,)")
148	n/a
149	n/a
150	n/a
151	n/a	class TestCause(unittest.TestCase):
152	n/a
153	n/a	def testCauseSyntax(self):
154	n/a	try:
155	n/a	try:
156	n/a	try:
157	n/a	raise TypeError
158	n/a	except Exception:
159	n/a	raise ValueError from None
160	n/a	except ValueError as exc:
161	n/a	self.assertIsNone(exc.__cause__)
162	n/a	self.assertTrue(exc.__suppress_context__)
163	n/a	exc.__suppress_context__ = False
164	n/a	raise exc
165	n/a	except ValueError as exc:
166	n/a	e = exc
167	n/a
168	n/a	self.assertIsNone(e.__cause__)
169	n/a	self.assertFalse(e.__suppress_context__)
170	n/a	self.assertIsInstance(e.__context__, TypeError)
171	n/a
172	n/a	def test_invalid_cause(self):
173	n/a	try:
174	n/a	raise IndexError from 5
175	n/a	except TypeError as e:
176	n/a	self.assertIn("exception cause", str(e))
177	n/a	else:
178	n/a	self.fail("No exception raised")
179	n/a
180	n/a	def test_class_cause(self):
181	n/a	try:
182	n/a	raise IndexError from KeyError
183	n/a	except IndexError as e:
184	n/a	self.assertIsInstance(e.__cause__, KeyError)
185	n/a	else:
186	n/a	self.fail("No exception raised")
187	n/a
188	n/a	def test_instance_cause(self):
189	n/a	cause = KeyError()
190	n/a	try:
191	n/a	raise IndexError from cause
192	n/a	except IndexError as e:
193	n/a	self.assertTrue(e.__cause__ is cause)
194	n/a	else:
195	n/a	self.fail("No exception raised")
196	n/a
197	n/a	def test_erroneous_cause(self):
198	n/a	class MyException(Exception):
199	n/a	def __init__(self):
200	n/a	raise RuntimeError()
201	n/a
202	n/a	try:
203	n/a	raise IndexError from MyException
204	n/a	except RuntimeError:
205	n/a	pass
206	n/a	else:
207	n/a	self.fail("No exception raised")
208	n/a
209	n/a
210	n/a	class TestTraceback(unittest.TestCase):
211	n/a
212	n/a	def test_sets_traceback(self):
213	n/a	try:
214	n/a	raise IndexError()
215	n/a	except IndexError as e:
216	n/a	self.assertIsInstance(e.__traceback__, types.TracebackType)
217	n/a	else:
218	n/a	self.fail("No exception raised")
219	n/a
220	n/a	def test_accepts_traceback(self):
221	n/a	tb = get_tb()
222	n/a	try:
223	n/a	raise IndexError().with_traceback(tb)
224	n/a	except IndexError as e:
225	n/a	self.assertNotEqual(e.__traceback__, tb)
226	n/a	self.assertEqual(e.__traceback__.tb_next, tb)
227	n/a	else:
228	n/a	self.fail("No exception raised")
229	n/a
230	n/a
231	n/a	class TestContext(unittest.TestCase):
232	n/a	def test_instance_context_instance_raise(self):
233	n/a	context = IndexError()
234	n/a	try:
235	n/a	try:
236	n/a	raise context
237	n/a	except:
238	n/a	raise OSError()
239	n/a	except OSError as e:
240	n/a	self.assertEqual(e.__context__, context)
241	n/a	else:
242	n/a	self.fail("No exception raised")
243	n/a
244	n/a	def test_class_context_instance_raise(self):
245	n/a	context = IndexError
246	n/a	try:
247	n/a	try:
248	n/a	raise context
249	n/a	except:
250	n/a	raise OSError()
251	n/a	except OSError as e:
252	n/a	self.assertNotEqual(e.__context__, context)
253	n/a	self.assertIsInstance(e.__context__, context)
254	n/a	else:
255	n/a	self.fail("No exception raised")
256	n/a
257	n/a	def test_class_context_class_raise(self):
258	n/a	context = IndexError
259	n/a	try:
260	n/a	try:
261	n/a	raise context
262	n/a	except:
263	n/a	raise OSError
264	n/a	except OSError as e:
265	n/a	self.assertNotEqual(e.__context__, context)
266	n/a	self.assertIsInstance(e.__context__, context)
267	n/a	else:
268	n/a	self.fail("No exception raised")
269	n/a
270	n/a	def test_c_exception_context(self):
271	n/a	try:
272	n/a	try:
273	n/a	1/0
274	n/a	except:
275	n/a	raise OSError
276	n/a	except OSError as e:
277	n/a	self.assertIsInstance(e.__context__, ZeroDivisionError)
278	n/a	else:
279	n/a	self.fail("No exception raised")
280	n/a
281	n/a	def test_c_exception_raise(self):
282	n/a	try:
283	n/a	try:
284	n/a	1/0
285	n/a	except:
286	n/a	xyzzy
287	n/a	except NameError as e:
288	n/a	self.assertIsInstance(e.__context__, ZeroDivisionError)
289	n/a	else:
290	n/a	self.fail("No exception raised")
291	n/a
292	n/a	def test_noraise_finally(self):
293	n/a	try:
294	n/a	try:
295	n/a	pass
296	n/a	finally:
297	n/a	raise OSError
298	n/a	except OSError as e:
299	n/a	self.assertTrue(e.__context__ is None)
300	n/a	else:
301	n/a	self.fail("No exception raised")
302	n/a
303	n/a	def test_raise_finally(self):
304	n/a	try:
305	n/a	try:
306	n/a	1/0
307	n/a	finally:
308	n/a	raise OSError
309	n/a	except OSError as e:
310	n/a	self.assertIsInstance(e.__context__, ZeroDivisionError)
311	n/a	else:
312	n/a	self.fail("No exception raised")
313	n/a
314	n/a	def test_context_manager(self):
315	n/a	class ContextManager:
316	n/a	def __enter__(self):
317	n/a	pass
318	n/a	def __exit__(self, t, v, tb):
319	n/a	xyzzy
320	n/a	try:
321	n/a	with ContextManager():
322	n/a	1/0
323	n/a	except NameError as e:
324	n/a	self.assertIsInstance(e.__context__, ZeroDivisionError)
325	n/a	else:
326	n/a	self.fail("No exception raised")
327	n/a
328	n/a	def test_cycle_broken(self):
329	n/a	# Self-cycles (when re-raising a caught exception) are broken
330	n/a	try:
331	n/a	try:
332	n/a	1/0
333	n/a	except ZeroDivisionError as e:
334	n/a	raise e
335	n/a	except ZeroDivisionError as e:
336	n/a	self.assertTrue(e.__context__ is None, e.__context__)
337	n/a
338	n/a	def test_reraise_cycle_broken(self):
339	n/a	# Non-trivial context cycles (through re-raising a previous exception)
340	n/a	# are broken too.
341	n/a	try:
342	n/a	try:
343	n/a	xyzzy
344	n/a	except NameError as a:
345	n/a	try:
346	n/a	1/0
347	n/a	except ZeroDivisionError:
348	n/a	raise a
349	n/a	except NameError as e:
350	n/a	self.assertTrue(e.__context__.__context__ is None)
351	n/a
352	n/a	def test_3118(self):
353	n/a	# deleting the generator caused the __context__ to be cleared
354	n/a	def gen():
355	n/a	try:
356	n/a	yield 1
357	n/a	finally:
358	n/a	pass
359	n/a
360	n/a	def f():
361	n/a	g = gen()
362	n/a	next(g)
363	n/a	try:
364	n/a	try:
365	n/a	raise ValueError
366	n/a	except:
367	n/a	del g
368	n/a	raise KeyError
369	n/a	except Exception as e:
370	n/a	self.assertIsInstance(e.__context__, ValueError)
371	n/a
372	n/a	f()
373	n/a
374	n/a	def test_3611(self):
375	n/a	# A re-raised exception in a __del__ caused the __context__
376	n/a	# to be cleared
377	n/a	class C:
378	n/a	def __del__(self):
379	n/a	try:
380	n/a	1/0
381	n/a	except:
382	n/a	raise
383	n/a
384	n/a	def f():
385	n/a	x = C()
386	n/a	try:
387	n/a	try:
388	n/a	x.x
389	n/a	except AttributeError:
390	n/a	del x
391	n/a	raise TypeError
392	n/a	except Exception as e:
393	n/a	self.assertNotEqual(e.__context__, None)
394	n/a	self.assertIsInstance(e.__context__, AttributeError)
395	n/a
396	n/a	with support.captured_output("stderr"):
397	n/a	f()
398	n/a
399	n/a	class TestRemovedFunctionality(unittest.TestCase):
400	n/a	def test_tuples(self):
401	n/a	try:
402	n/a	raise (IndexError, KeyError) # This should be a tuple!
403	n/a	except TypeError:
404	n/a	pass
405	n/a	else:
406	n/a	self.fail("No exception raised")
407	n/a
408	n/a	def test_strings(self):
409	n/a	try:
410	n/a	raise "foo"
411	n/a	except TypeError:
412	n/a	pass
413	n/a	else:
414	n/a	self.fail("No exception raised")
415	n/a
416	n/a
417	n/a	if __name__ == "__main__":
418	n/a	unittest.main()