PLAT-156: Migrate test_fetch #1129
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ethho
commented
Dec 12, 2023
ethho
commented
- Changes in PLAT-154: Migrate test_external #1127
- Changes in PLAT-155: Migrate test_external_class #1128
- cp to tests
- First pass at migrating test_fetch
test_decimal fails because its contents, a zip object, are exhausted by a previous test. Reproduce by seeing a pass then a fail when running pytest -k 'test_offset or test_decimal' tests/test_fetch.py
The following command now passes, as do all tests in this module: pytest -k 'test_offset or test_decimal' tests/test_fetch.py
| @pytest.fixture | ||
| def languages(lang) -> List: | ||
| og_contents = lang.contents | ||
| languages = og_contents.copy() |
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I had to copy, store, and restore the contents of this table because the contents would change between tests. This caused some tests such as test_fetch1_step1 to fail if other tests (that sort contents) such as test_order_by were run before it.
| assert set(result[0]) == set(attrs) | ||
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| def test_fetch1_step1(self, schema_any, lang, languages): | ||
| assert ( |
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Added this assertion to check if upstream tests like test_offset_by changed the contents and broke this test.
| @@ -307,7 +307,7 @@ class DecimalPrimaryKey(dj.Lookup): | |||
| definition = """ | |||
| id : decimal(4,3) | |||
| """ | |||
| contents = zip((0.1, 0.25, 3.99)) | |||
| contents = list(zip((0.1, 0.25, 3.99))) | |||
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Strangely, the logic in test_fetch::test_offset would exhaust this zip object, causing it to be empty when test_fetch::test_decimal was run, causing the latter test to fail.
It's possible that ORDER BY on the upstream table causes DecimalPrimaryKey to also sort (and therefore exhaust the zip object):
def test_offset(self, schema_any, lang, languages):
"""Tests offset"""
cur = lang.fetch(limit=4, offset=1, order_by=["language", "name DESC"])Whatever the cause, changing the contents from a zip to a list prevents these tests from interfering with each other.
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zip can only be used once. Once exhausted, it's empty. So if you are using the same code more than once to populate a lookup table, you need to convert into a list first.
