Opened 10 years ago
Closed 10 years ago
#24148 closed Bug (fixed)
test_combined_expression test failure on Windows/Python 2
Reported by: | Tim Graham | Owned by: | Michał Modzelewski |
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Component: | Database layer (models, ORM) | Version: | dev |
Severity: | Release blocker | Keywords: | |
Cc: | Michał Modzelewski | Triage Stage: | Accepted |
Has patch: | yes | Needs documentation: | no |
Needs tests: | no | Patch needs improvement: | no |
Easy pickings: | no | UI/UX: | no |
Description
===================================================================== FAIL: test_combined_expression (expressions_case.tests.CaseExpressionTests) ---------------------------------------------------------------------- Traceback (most recent call last): File "c:\Users\Tim\code\django\tests\expressions_case\tests.py", line 257, in test_combined_expression transform=attrgetter('integer', 'test') File "c:\users\tim\code\django\django\test\testcases.py", line 883, in assertQ uerysetEqual return self.assertEqual(list(items), values, msg=msg) AssertionError: Lists differ: [(1, 3), (2, 3), (3, 4), (2, 3... != [(1, 3), (2, 2), (3, 4), (2, 2... First differing element 1: (2, 3) (2, 2) - [(1, 3), (2, 3), (3, 4), (2, 3), (3, 4), (3, 4), (4, 4)] ? ^ ^ + [(1, 3), (2, 2), (3, 4), (2, 2), (3, 4), (3, 4), (4, 4)] ? ^ ^
No problem on Python 3.4.
Change History (6)
comment:1 by , 10 years ago
Cc: | added |
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comment:2 by , 10 years ago
Owner: | changed from | to
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Status: | new → assigned |
Reproduced. I'll look into it.
comment:3 by , 10 years ago
I've had a look and it's not pretty. The SQL generated in pythons 2.7, 3.2, 3.3 and 3.4 on windows is exactly the same.
sqlite3.version is 2.6.0 on all of them.
What differs is sqlite3.sqlite_version:
- py2.7: 3.6.21
- py3.2: 3.7.4
- py3.3: 3.7.12
- py3.4: 3.8.3.1
I installed pysqlite from http://www.lfd.uci.edu/~gohlke/pythonlibs/ (2.6.3 / 3.8.5) and the test passes.
What is happening? SQLite is adding the value in the lookup to the value in the then.
You can see this better with a different example (with the same test data as the testcase):
>>> qs = CaseTestModel.objects.annotate( ... test=Case( ... When(integer=1, then=Value(1)), ... When(integer=2, then=Value(1)), ... When(integer=3, then=Value(1)), ... When(integer=4, then=Value(10)), ... default=Value(1), ... output_field=models.IntegerField(), ... ) + 100, ... ).order_by('pk') >>> # expected: [(1, 101), (2, 101), (3, 101), (2, 101), (3, 101), (3, 101), (4, 110)] >>> [(o.integer, o.test) for o in qs] [(1, 2), (2, 3), (3, 4), (2, 3), (3, 4), (3, 4), (4, 14)]
Removing the default fixes it (since all the cases are taken care of)
>>> qs = CaseTestModel.objects.annotate( ... test=Case( ... When(integer=1, then=Value(1)), ... When(integer=2, then=Value(1)), ... When(integer=3, then=Value(1)), ... When(integer=4, then=Value(10)), ... # default=Value(1), ... output_field=models.IntegerField(), ... ) + 100, ... ).order_by('pk') >>> # expected: [(1, 101), (2, 101), (3, 101), (2, 101), (3, 101), (3, 101), (4, 110)] >>> [(o.integer, o.test) for o in qs] [(1, 101), (2, 101), (3, 101), (2, 101), (3, 101), (3, 101), (4, 110)]
Also, if I send the query as a string without the placeholders it works. So I assume that SQLite 3.6.21 is mixing up the query parameters. Not sure if the error is specific to this version, but it seems there was a query related bug fix in 3.6.22 (http://www.sqlite.org/changes.html#version_3_6_22 ).
Unfortunately, I checked all the windows python versions from 2.7a1 to 2.7.9 and they all have the same sqlite3.sqlite_version, so there's nothing we can do here other than mark the test as an expected failure and recommend pysqlite on windows.
comment:5 by , 10 years ago
Has patch: | set |
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I've done some testing, and SQLite 3.7.0 is the first version that passes this test case.
PR is ready.
comment:6 by , 10 years ago
Resolution: | → fixed |
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Status: | assigned → closed |
Michał, any chance you have access to Windows and can reproduce this? If not, I can give you access to a system if you're willing to help debug this.