Enable CI and pre-commit hook to lint tests (#4335)

* rename all legacy test files to match pylint pattern

* pylint all tests in CI and pre-commit

* lint legacy/qnn/conftest

* remove the custom pylint test handling

* run black before pylint

* changelog

---------

Co-authored-by: David Wierichs <david.wierichs@xanadu.ai>

.github/workflows/pylint.yml

@@ -40,28 +40,10 @@ jobs:
  extra-mypy-options: ""
  extra-isort-options: ""
 
- - name: Check for new test files that need whitelisting
- uses: dorny/paths-filter@v2
- id: test_files_added
- with:
- list-files: shell
- filters: |
- testsAdded:
- - added: 'tests/**/test_*.py'
- - added: 'tests/test_*.py'
-
- - name: Ensure new test files are whitelisted if there are any
- if: steps.test_files_added.outputs.testsAdded == 'true'
- run: ./.github/workflows/scripts/validate_new_tests.sh ${{ steps.test_files_added.outputs.testsAdded_files }}
-
- - name: Read whitelisted test files that pass pylint
- id: tests_to_lint
- run: echo "testfiles=$(cat tests/tests_passing_pylint.txt | tr '\n' ' ')" >> $GITHUB_OUTPUT
-
- - name: Run pylint for whitelisted tests
+ - name: Run pylint (tests)
  uses: ricardochaves/python-lint@v1.4.0
  with:
- python-root-list: "${{ steps.tests_to_lint.outputs.testfiles }}"
+ python-root-list: "tests"
  use-pylint: True
  use-pycodestyle: false
  use-flake8: false

.pre-commit-config.yaml

@@ -1,4 +1,9 @@
 repos:
+- repo: https://github.com/psf/black
+ rev: 22.3.0
+ hooks:
+ - id: black
+ exclude: ^doc/
 - repo: local
  hooks:
  - id: pylint
@@ -13,8 +18,15 @@ repos:
  "--rcfile=.pylintrc", # Link to your config file
  ]
  exclude: ^(doc/|tests/)
-- repo: https://github.com/psf/black
- rev: 22.3.0
- hooks:
- - id: black
- exclude: ^doc/
+ - id: pylint-test
+ name: pylint-test
+ entry: pylint
+ language: system
+ types: [python]
+ args:
+ [
+ "-rn", # Only display messages
+ "-sn", # Don't display the score
+ "--rcfile=tests/.pylintrc", # Link to your config file
+ ]
+ files: ^tests/

doc/releases/changelog-dev.md

@@ -7,7 +7,10 @@
 <h3>Improvements 🛠</h3>
 
 * `PauliWord` sparse matrices are much faster, which directly improves `PauliSentence`.
- [#4272](https://github.com/PennyLaneAI/pennylane/pull/4272)
+ [(#4272)](https://github.com/PennyLaneAI/pennylane/pull/4272)
+
+* Enable linting of all tests in CI and the pre-commit hook.
+ [(#4335)](https://github.com/PennyLaneAI/pennylane/pull/4335)
 
 * Added a function `qml.math.fidelity_statevector` that computes the fidelity between two state vectors.
  [(#4322)](https://github.com/PennyLaneAI/pennylane/pull/4322)

tests/.pylintrc

@@ -3,6 +3,7 @@
 # be loaded. Extensions are loading into the active Python interpreter and may
 # run arbitrary code
 extension-pkg-whitelist=numpy,scipy,autograd,toml,appdir,autograd.numpy,autograd.numpy.linalg,autograd.numpy.builtins,semantic_version,torch,tensorflow,tensorflow.contrib,tensorflow.contrib.eager,LazyLoader,networkx,networkx.dag
+ignore-patterns=test_legacy*
 
 [TYPECHECK]
 

tests/legacy/qnn/conftest.py

@@ -15,8 +15,8 @@
 Common fixtures for the qnn module.
 """
 import pytest
-import pennylane as qml
 import numpy as np
+import pennylane as qml
 
 
 @pytest.fixture
@@ -36,7 +36,7 @@ def get_circuit(n_qubits, output_dim, interface):
  }
 
  @qml.qnode(dev, interface=interface)
- def circuit(inputs, w1, w2, w3, w4, w5, w6, w7):
+ def circuit(inputs, w1, w2, w3, w4, w5, w6, w7): # pylint:disable=too-many-arguments
  """A circuit that embeds data using the AngleEmbedding and then performs a variety of
  operations. The output is a PauliZ measurement on the first output_dim qubits. One set of
  parameters, w5, are specified as non-trainable."""
@@ -71,7 +71,7 @@ def get_circuit_dm(n_qubits, output_dim, interface):
  }
 
  @qml.qnode(dev, interface=interface)
- def circuit(inputs, w1, w2, w3, w4, w5, w6, w7):
+ def circuit(inputs, w1, w2, w3, w4, w5, w6, w7): # pylint:disable=too-many-arguments
  """Sample circuit to be used for testing density_matrix() return type."""
  qml.templates.AngleEmbedding(inputs, wires=list(range(n_qubits)))
  qml.templates.StronglyEntanglingLayers(w1, wires=list(range(n_qubits)))
@@ -84,6 +84,6 @@ def circuit(inputs, w1, w2, w3, w4, w5, w6, w7):
 
  # Using np.log2() here because output_dim is sampled from varying the number of
  # qubits (say, nq) and calculated as (2 ** nq, 2 ** nq)
- return qml.density_matrix(wires=[i for i in range(int(np.log2(output_dim[0])))])
+ return qml.density_matrix(wires=list(range(int(np.log2(output_dim[0])))))
 
  return circuit, weight_shapes