STY: Apply ruff/Perflint rule PERF401

PERF401 Use a list comprehension to create a transformed list

Author: DimitriPapadopoulos

nibabel/data.py

@@ -87,8 +87,7 @@ def list_files(self, relative=True):
         for base, dirs, files in os.walk(self.base_path):
             if relative:
                 base = base[len(self.base_path) + 1 :]
-            for filename in files:
-                out_list.append(pjoin(base, filename))
+            out_list.extend(pjoin(base, filename) for filename in files)
         return out_list
 
 

nibabel/nicom/tests/test_dicomwrappers.py

@@ -429,10 +429,9 @@ def fake_shape_dependents(
 
     class PrintBase:
         def __repr__(self):
-            attr_strs = []
-            for attr in dir(self):
-                if attr[0].isupper():
-                    attr_strs.append(f'{attr}={getattr(self, attr)}')
+            attr_strs = [
+                f'{attr}={getattr(self, attr)}' for attr in dir(self) if attr[0].isupper()
+            ]
             return f"{self.__class__.__name__}({', '.join(attr_strs)})"
 
     class DimIdxSeqElem(pydicom.Dataset):

nibabel/tests/test_euler.py

@@ -21,12 +21,8 @@
 FLOAT_EPS = np.finfo(np.float64).eps
 
 # Example rotations """
-eg_rots = []
 params = np.arange(-pi * 2, pi * 2.5, pi / 2)
-for x in params:
-    for y in params:
-        for z in params:
-            eg_rots.append((x, y, z))
+eg_rots = [(x, y, z) for x in params for y in params for z in params]
 
 
 def x_only(x):

nibabel/tests/test_filehandles.py

@@ -33,8 +33,7 @@ def test_multiload():
         tmpdir = mkdtemp()
         fname = pjoin(tmpdir, 'test.img')
         save(img, fname)
-        for i in range(N):
-            imgs.append(load(fname))
+        imgs.extend(load(fname) for i in range(N))
     finally:
         del img, imgs
         shutil.rmtree(tmpdir)