Move to nose2 only by klecki · Pull Request #6146 · NVIDIA/DALI

klecki · 2025-12-22T15:34:18Z

Use nose2 as the only testing framework. Drop nose.

Category: Other

Description:

Remove the WARs used to keep nose alive.

nose2 supports the yield-style test discovery by default @attr has a different filtering syntax (-A) and just checks for presence of truthy test_foo.attribute_name. A decorator uses this mechanism for backward compatibility.

nose2 splits with_setup(setup, teardown) into two separate decorators, a backward compatible decorator is added.

nottest sets special attribute.

SkipTest from unittest is recommended to be used directly (with the same functionality).

Test scripts are adjusted with minimal changes to run through nose2. Followup cleanup can be used for renaming.

Replace unsupported -m regex by attributes

Additional information:

Affected modules and functionalities:

Key points relevant for the review:

Tests:

Checklist

Documentation

DALI team only

Requirements

Implements new requirements
Affects existing requirements
N/A

REQ IDs: N/A

JIRA TASK: N/A

greptile-apps · 2025-12-22T15:38:54Z

Greptile Summary

This PR completes the migration from nose to nose2 as the sole Python test runner for DALI. It removes the nose_wrapper shim (and all the imp/pkg_resources compatibility hacks it required), rewrites nose_utils.py using only unittest primitives, introduces a new nose2_attrib_generators plugin to attribute-filter generator-style tests before they are invoked, and updates all 50+ CI shell scripts to use python_new_invoke_test with -A attribute filters instead of --attr.

Confidence Score: 5/5

Safe to merge; all previously flagged P1 issues have been resolved, and the one remaining finding is a minor P2 about plain-class setUp lifecycle.

Prior blocking issues (missing sanitizer_skip attributes, --attr vs -A syntax, .1 vs :1 parameterized selector, missing comma in attribute expressions) are all resolved in the current HEAD. The only open finding is a P2 concern about TestTFDatasetMultiGPU and similar plain classes not inheriting unittest.TestCase, which may affect setUp call guarantees when tests are loaded by explicit name — not a hard blocker.

dali/test/python/test_dali_tf_dataset_eager.py — verify setUp is called for plain-class tests invoked by explicit name via nose2.

Important Files Changed

Filename	Overview
dali/test/python/nose2_attrib_generators.py	New nose2 plugin that monkey-patches the Generators plugin to apply -A attribute filters before calling generator functions; comment added explaining the intentional duplication of nose2's internal parsing logic.
dali/test/python/nose_utils.py	Massively simplified by dropping all nose/imp/pkg_resources shims; replaces nose APIs with pure unittest equivalents (SkipTest, attr, nottest, assert_raises, assert_warns). Logic looks correct.
dali/test/python/test_dali_tf_dataset_eager.py	Refactored free functions with with_setup into plain classes with setUp; TestTFDatasetMultiGPU does not inherit unittest.TestCase, raising a P2 concern about setUp lifecycle when loaded by explicit name.
dali/test/python/unittest.cfg	Added nose2_attrib_generators plugin before nose2.plugins.attrib so generator functions are filtered by attributes before being called.
qa/test_template_impl.sh	Drops python_invoke_test/python_test_runner (nose) variables entirely; nose2 is now the sole runner; pip_packages trimmed to nose2 nose2-test-timer.
qa/nose_wrapper/main.py	Deleted — the nose wrapper shim (including inspect.getargspec patch and run_exit) is no longer needed.
qa/TL0_python-self-test-core/test_body.sh	Migrated all invocations from python_invoke_test --attr to python_new_invoke_test -A; mxnet attribute removed; parameterized test uses correct :1 colon separator.
qa/TL1_tensorflow_dataset/test_impl.sh	Migrated TF-dataset multi-GPU test invocations to nose2 module-path syntax; _test_tf_dataset_multigpu_mirrored_strategy now correctly referenced under TestTFDatasetMultiGPU class.
qa/TL0_python_self_test_frameworks/test_pytorch.sh	Replaced -m regex test-name filter with -A pytorch attribute filter; tests must now carry @attr('pytorch') to be discovered.
dali/test/python/test_fw_iterators.py	Removed ~1140 lines of MXNet-specific iterator tests (mxnet attribute gated), consistent with the mxnet filter removal across CI scripts.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A[CI shell script] -->|python_new_invoke_test -A filter module.Class.method| B[python -m nose2]
    B --> C{unittest.cfg plugins}
    C --> D[nose2_attrib_generators\nAttributeGeneratorFilter]
    C --> E[nose2.plugins.attrib\nAttributeSelector]
    C --> F[nose2.plugins.collect]
    D -->|handleArgs: monkey-patches| G[Generators plugin\n_testsFromGeneratorFunc]
    G -->|check @attr tags before calling| H{Attribute match?}
    H -- No --> I[return empty list\nskip generator]
    H -- Yes --> J[call generator - yield tests]
    E -->|moduleLoadedSuite: filter| K[Individual test methods\nwith @attr tags]
    J --> K
    K --> L[Run tests]

_{Reviews (22): Last reviewed commit: "Fix" | Re-trigger Greptile}

greptile-apps

Additional Comments (1)

dali/test/python/nose_utils.py, line 129-130 (link)

style: creating a new TestCase instance for each assertion call is unconventional

Consider creating a module-level instance once:

Then define tc at module level (after imports) and reuse it in both assert_raises and assert_warns

_{Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!}

_{25 files reviewed, 1 comment}

_{Edit Code Review Agent Settings | Greptile}

greptile-apps

Additional Comments (2)

dali/test/python/test_functional_api.py, line 22 (link)

logic: This file still imports nose directly and uses nose.tools.eq_ on line 188. Since nose is being removed as a dependency, this will cause an import error.
dali/test/python/test_functional_api.py, line 188 (link)

logic: Replace nose.tools.eq_ with standard assertion or use assert_equals from nose_utils

_{Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!}

_{28 files reviewed, 2 comments}

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greptile-apps

Additional Comments (1)

dali/test/python/nose_utils.py, line 68 (link)

syntax: missing self parameter - instance methods must have self as first parameter

_{29 files reviewed, 1 comment}

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klecki · 2025-12-22T16:12:40Z

!build

dali-automaton · 2025-12-22T16:15:21Z

CI MESSAGE: [40627092]: BUILD STARTED

dali-automaton · 2025-12-22T16:29:31Z

CI MESSAGE: [40627092]: BUILD FAILED

klecki · 2025-12-22T16:37:35Z

!build

dali-automaton · 2025-12-22T16:40:40Z

CI MESSAGE: [40628704]: BUILD STARTED

greptile-apps

Additional Comments (1)

dali/test/python/nose_utils.py, line 83-85 (link)

style: Consider using the module-level _test_case instance instead of creating a new empty_case() for each assertion:

This is more efficient and aligns with how assert_raises and assert_warns are implemented.

_{Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!}

_{29 files reviewed, 1 comment}

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JanuszL · 2025-12-22T17:09:25Z

Do we need to touch unittest_failure.cfg, unittest_slow.cfg or unittest.cfg as well?

dali-automaton · 2025-12-22T18:58:23Z

CI MESSAGE: [40628704]: BUILD FAILED

mzient

The way the tests are first discovered and then run will most certainly prevent parallel external source from working (see test job 247483858) was the primary reason for not pursuing full transition to nose2 to date.
Perhaps you can move the troublesome tests to separate files to guarantee proper execution order.

Also, some of the tests used to generate vast amounts of data in the "discovery" stage, because yielding in nose didn't cause data accumulation. Please make sure that this is not the case any more - the tests might work when run one by one but case out-of-memory condition when multiple test files are run.

greptile-apps

Additional Comments (1)

dali/test/python/nose_utils.py, line 74 (link)

syntax: Missing self parameter in method definition

_{33 files reviewed, 1 comment}

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greptile-apps · 2025-12-30T15:25:31Z

Greptile's behavior is changing!

From now on, if a review finishes with no comments, we will not post an additional "statistics" comment to confirm that our review found nothing to comment on. However, you can confirm that we reviewed your changes in the status check section.

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Signed-off-by: Krzysztof Lecki <klecki@nvidia.com>

Signed-off-by: Janusz Lisiecki <jlisiecki@nvidia.com>

- nose_utils.py: consolidate double unittest import into single form - test_dali_tf_es_pipelines.py: gen_tf_with_dali_external_source now yields a make_es_args factory instead of pre-built callback objects, so no data is created during test discovery - test_dali_tf_dataset_graph.py: call make_es_args() at test run time - test_external_source_parallel.py: _make_all_kinds_parallel_cases yields (epoch_size, ...) descriptors; ExtCallback/SampleCallbackBatched/ SampleCallbackIterator are constructed inside test_all_kinds_parallel Signed-off-by: Janusz Lisiecki <jlisiecki@nvidia.com>

test_numba_func_with_cond tests passed np.full(...) directly in expected_out and were not updated when the descriptor format was introduced in 839dfb1, causing a ValueError on unpack. Signed-off-by: Janusz Lisiecki <jlisiecki@nvidia.com>

Signed-off-by: Janusz Lisiecki <jlisiecki@nvidia.com>

mzient · 2026-04-20T16:30:27Z


    if [ -z "$DALI_ENABLE_SANITIZERS" ]; then
-        ${python_new_invoke_test} -A "!slow,!pytorch,!mxnet,!cupy" test_dali_variable_batch_size
+        ${python_new_invoke_test} -A "!slow,!pytorch!cupy" test_dali_variable_batch_size


Suggested change

${python_new_invoke_test} -A "!slow,!pytorch!cupy" test_dali_variable_batch_size

${python_new_invoke_test} -A "!slow,!pytorch,!cupy" test_dali_variable_batch_size

mzient · 2026-04-20T16:30:38Z

+        ${python_new_invoke_test} -A "!slow,!pytorch!cupy" test_dali_variable_batch_size
    else
-        ${python_new_invoke_test} -A "!slow,!pytorch,!mxnet,!cupy,!numba" test_dali_variable_batch_size
+        ${python_new_invoke_test} -A "!slow,!pytorch!cupy,!numba" test_dali_variable_batch_size


Suggested change

${python_new_invoke_test} -A "!slow,!pytorch!cupy,!numba" test_dali_variable_batch_size

${python_new_invoke_test} -A "!slow,!pytorch,!cupy,!numba" test_dali_variable_batch_size

Signed-off-by: Janusz Lisiecki <jlisiecki@nvidia.com>

JanuszL · 2026-04-20T17:59:01Z

!build

Signed-off-by: Janusz Lisiecki <jlisiecki@nvidia.com>

dali-automaton · 2026-04-20T18:06:40Z

CI MESSAGE: [49014072]: BUILD STARTED

dali-automaton · 2026-04-20T18:24:12Z

CI MESSAGE: [49014072]: BUILD FAILED

Signed-off-by: Janusz Lisiecki <jlisiecki@nvidia.com>

JanuszL · 2026-04-20T18:31:07Z

!build

dali-automaton · 2026-04-20T18:35:49Z

CI MESSAGE: [49016580]: BUILD STARTED

dali-automaton · 2026-04-20T22:00:56Z

CI MESSAGE: [49016580]: BUILD FAILED

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Comment thread dali/test/python/nose_utils.py Fixed

Comment thread dali/test/python/nose_utils.py Fixed

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Comment thread dali/test/python/nose_utils.py Fixed

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klecki mentioned this pull request Dec 22, 2025

Add pkg_resources compatibility fallback using importlib.metadata #6144

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