TEST: refactor complex functions

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[sourcery-ai[bot]]

Sourcery Code Quality Report

✅  Merging this PR will increase code quality in the affected files by 4.62%.

Quality metrics	Before	After	Change
Complexity	23.12 😞	14.38 🙂	-8.74 👍
Method Length	179.49 😞	159.39 😞	-20.10 👍
Working memory	14.17 😞	13.83 😞	-0.34 👍
Quality	42.68% 😞	47.30% 😞	4.62% 👍

Other metrics	Before	After	Change
Lines	7836	8030	194

Changed files	Quality Before	Quality After	Quality Change
nilearn/connectome/group_sparse_cov.py	25.20% 😞	31.38% 😞	6.18% 👍
nilearn/connectome/tests/test_group_sparse_cov.py	52.96% 🙂	52.96% 🙂	0.00%
nilearn/datasets/func.py	46.71% 😞	51.49% 🙂	4.78% 👍
nilearn/datasets/tests/test_func.py	70.33% 🙂	70.95% 🙂	0.62% 👍
nilearn/glm/first_level/first_level.py	21.61% ⛔	24.78% ⛔	3.17% 👍
nilearn/image/resampling.py	28.56% 😞	36.43% 😞	7.87% 👍
nilearn/image/tests/test_resampling.py	61.73% 🙂	61.73% 🙂	0.00%
nilearn/mass_univariate/permuted_least_squares.py	3.57% ⛔	25.17% 😞	21.60% 👍

Here are some functions in these files that still need a tune-up:

File	Function	Complexity	Length	Working Memory	Quality	Recommendation
nilearn/glm/first_level/first_level.py	first_level_from_bids	84 ⛔	834 ⛔	39 ⛔	0.66% ⛔	Refactor to reduce nesting. Try splitting into smaller methods. Extract out complex expressions
nilearn/connectome/group_sparse_cov.py	_group_sparse_covariance	64 ⛔	1018 ⛔	34 ⛔	1.87% ⛔	Refactor to reduce nesting. Try splitting into smaller methods. Extract out complex expressions
nilearn/image/resampling.py	resample_img	42 ⛔	818 ⛔	26 ⛔	6.63% ⛔	Refactor to reduce nesting. Try splitting into smaller methods. Extract out complex expressions
nilearn/glm/first_level/first_level.py	FirstLevelModel.fit	57 ⛔	752 ⛔	18 ⛔	7.70% ⛔	Refactor to reduce nesting. Try splitting into smaller methods. Extract out complex expressions
nilearn/mass_univariate/permuted_least_squares.py	permuted_ols	35 ⛔	855 ⛔	30 ⛔	8.16% ⛔	Refactor to reduce nesting. Try splitting into smaller methods. Extract out complex expressions

Legend and Explanation

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Codecov Report

:exclamation: No coverage uploaded for pull request base (flake8_cfg@6b25303). Click here to learn what that means. The diff coverage is n/a.

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  Coverage              ?   91.09%           
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  Files                 ?      133           
  Lines                 ?    15387           
  Branches              ?     3028           
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  Hits                  ?    14017           
  Misses                ?      809           
  Partials              ?      561           

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