avoid module level variable

tests/io/cp2k/test_inputs.py

@@ -26,19 +26,6 @@
 
 TEST_DIR = f"{TEST_FILES_DIR}/io/cp2k"
 
-si_struct = Structure(
-    lattice=[[0, 2.734364, 2.734364], [2.734364, 0, 2.734364], [2.734364, 2.734364, 0]],
-    species=["Si", "Si"],
-    coords=[[0, 0, 0], [0.25, 0.25, 0.25]],
-)
-
-nonsense_struct = Structure(
-    lattice=[[-1.0, -10.0, -100.0], [0.1, 0.01, 0.001], [7.0, 11.0, 21.0]],
-    species=["H"],
-    coords=[[-1, -1, -1]],
-)
-
-ch_mol = Molecule(species=["C", "H"], coords=[[0, 0, 0], [1, 1, 1]])
 
 BASIS_FILE_STR = """
  H  SZV-MOLOPT-GTH SZV-MOLOPT-GTH-q1
@@ -52,26 +39,22 @@
       0.066918004004  0.037148121400
       0.021708243634 -0.001125195500
 """
-ALL_HYDROGEN_STR = """
+
+
+class TestBasisAndPotential(PymatgenTest):
+    all_hydrogen_str = """
 H ALLELECTRON ALL
     1    0    0
-     0.20000000    0
+    0.20000000    0
 """
-POT_HYDROGEN_STR = """
+
+    pot_hydrogen_str = """
 H GTH-PBE-q1 GTH-PBE
     1
-     0.20000000    2    -4.17890044     0.72446331
+    0.20000000    2    -4.17890044     0.72446331
     0
 """
-CP2K_INPUT_STR = """
-&GLOBAL
-    RUN_TYPE ENERGY
-    PROJECT_NAME CP2K ! default name
-&END
-"""
-
 
-class TestBasisAndPotential(PymatgenTest):
     def test_basis_info(self):
         # Ensure basis metadata can be read from string
         basis_info = BasisInfo.from_str("cc-pc-DZVP-MOLOPT-q1-SCAN")
@@ -135,20 +118,20 @@ def test_basis(self):
 
     def test_potentials(self):
         # Ensure cp2k formatted string can be read for data correctly
-        h_all_elec = GthPotential.from_str(ALL_HYDROGEN_STR)
+        h_all_elec = GthPotential.from_str(self.all_hydrogen_str)
         assert h_all_elec.potential == "All Electron"
-        pot = GthPotential.from_str(POT_HYDROGEN_STR)
+        pot = GthPotential.from_str(self.pot_hydrogen_str)
         assert pot.potential == "Pseudopotential"
         assert pot.r_loc == approx(0.2)
         assert pot.nexp_ppl == approx(2)
         assert_allclose(pot.c_exp_ppl, [-4.17890044, 0.72446331])
 
         # Basis file can read from strings
-        pot_file = PotentialFile.from_str(POT_HYDROGEN_STR)
+        pot_file = PotentialFile.from_str(self.pot_hydrogen_str)
         assert pot_file.objects[0] == pot
 
         pot_file_path = self.tmp_path / "potential-file"
-        pot_file_path.write_text(POT_HYDROGEN_STR)
+        pot_file_path.write_text(self.pot_hydrogen_str)
         pot_from_file = PotentialFile.from_file(pot_file_path)
         assert pot_file != pot_from_file  # unequal because pot_from_file has filename != None
 
@@ -160,11 +143,32 @@ def test_potentials(self):
 
 
 class TestCp2kInput(PymatgenTest):
+    si_struct = Structure(
+        lattice=[[0, 2.734364, 2.734364], [2.734364, 0, 2.734364], [2.734364, 2.734364, 0]],
+        species=["Si", "Si"],
+        coords=[[0, 0, 0], [0.25, 0.25, 0.25]],
+    )
+
+    invalid_struct = Structure(
+        lattice=[[-1.0, -10.0, -100.0], [0.1, 0.01, 0.001], [7.0, 11.0, 21.0]],
+        species=["H"],
+        coords=[[-1, -1, -1]],
+    )
+
+    ch_mol = Molecule(species=["C", "H"], coords=[[0, 0, 0], [1, 1, 1]])
+
+    cp2k_input_str = """
+&GLOBAL
+    RUN_TYPE ENERGY
+    PROJECT_NAME CP2K ! default name
+&END
+"""
+
     def setUp(self):
         self.ci = Cp2kInput.from_file(f"{TEST_DIR}/cp2k.inp")
 
     def test_basic_sections(self):
-        cp2k_input = Cp2kInput.from_str(CP2K_INPUT_STR)
+        cp2k_input = Cp2kInput.from_str(self.cp2k_input_str)
         assert cp2k_input["GLOBAL"]["RUN_TYPE"] == Keyword("RUN_TYPE", "energy")
         assert cp2k_input["GLOBAL"]["PROJECT_NAME"].description == "default name"
         self.assert_msonable(cp2k_input)
@@ -190,13 +194,13 @@ def test_basic_keywords(self):
         assert "[Ha]" in kwd.get_str()
 
     def test_coords(self):
-        for struct in [nonsense_struct, si_struct, ch_mol]:
+        for struct in (self.invalid_struct, self.si_struct, self.ch_mol):
             coords = Coord(struct)
             for val in coords.keywords.values():
                 assert isinstance(val, Keyword | KeywordList)
 
     def test_kind(self):
-        for struct in [nonsense_struct, si_struct, ch_mol]:
+        for struct in (self.invalid_struct, self.si_struct, self.ch_mol):
             for spec in struct.species:
                 assert spec == Kind(spec).specie
 
@@ -246,7 +250,7 @@ def test_preprocessor(self):
         assert self.ci["FORCE_EVAL"]["DFT"]["SCF"]["MAX_SCF"] == Keyword("MAX_SCF", 1)
 
     def test_mongo(self):
-        cp2k_input = Cp2kInput.from_str(CP2K_INPUT_STR)
+        cp2k_input = Cp2kInput.from_str(self.cp2k_input_str)
         cp2k_input.inc({"GLOBAL": {"TEST": 1}})
         assert cp2k_input["global"]["test"] == Keyword("TEST", 1)