[MAINT] add workflow to check for f strings

.github/workflows/f_strings.yml

@@ -0,0 +1,31 @@
+---
+name: f strings
+
+on:
+  push:
+    branches:
+      - "main"
+  pull_request:
+    branches:
+      - "*"
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  f_strings:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - uses: actions/setup-python@v4
+        with:
+          python-version: "3.11"
+
+      - name: "Install flynt"
+        shell: bash {0}
+        run: python -m pip install --upgrade pip flynt
+
+      - name: "Run isort"
+        run: flynt .

examples/01_plotting/plot_surf_atlas.py

@@ -35,12 +35,12 @@
 fsaverage = datasets.fetch_surf_fsaverage()
 
 # The fsaverage dataset contains file names pointing to the file locations
-print('Fsaverage5 pial surface of left hemisphere is at: %s' %
-      fsaverage['pial_left'])
-print('Fsaverage5 inflated surface of left hemisphere is at: %s' %
-      fsaverage['infl_left'])
-print('Fsaverage5 sulcal depth map of left hemisphere is at: %s' %
-      fsaverage['sulc_left'])
+print("Fsaverage5 pial surface of left hemisphere is at: "
+      f"{fsaverage['pial_left']}")
+print("Fsaverage5 inflated surface of left hemisphere is at: "
+      f"{fsaverage['infl_left']}")
+print("Fsaverage5 sulcal depth map of left hemisphere is at: "
+      f"{fsaverage['sulc_left']}")
 
 ###############################################################################
 # Visualization

nilearn/_utils/data_gen.py

@@ -677,7 +677,7 @@ def generate_group_sparse_gaussian_graphs(n_subjects=5,
     topology = topology > 0
     assert (np.all(topology == topology.T))
     logger.log(
-        "Sparsity: {0:f}".format(1. * topology.sum() / (topology.shape[0]**2)),
+        f"Sparsity: {1.0 * topology.sum() / topology.shape[0] ** 2:f}",
         verbose=verbose)
 
     # Generate temporal signals

nilearn/_utils/docs.py

@@ -902,6 +902,5 @@
     except (TypeError, ValueError, KeyError) as exp:
         funcname = f.__name__
         funcname = docstring.split('\n')[0] if funcname is None else funcname
-        raise RuntimeError('Error documenting %s:\n%s'
-                           % (funcname, str(exp)))
+        raise RuntimeError(f'Error documenting {funcname}:\n{str(exp)}')
     return f

pyproject.toml

@@ -183,3 +183,6 @@ junit_family = "xunit2"
 [tool.codespell]
 skip = "./.git,plotly-gl3d-latest.min.js,jquery.min.js,localizer_behavioural.tsv,.mypy_cache,env,venv,./doc/auto_examples"
 ignore-words = ".github/codespell_ignore_words.txt"
+
+[tool.flynt]
+exclude = "tempita"