ruff . --fix (#3176)

64 cases of RUF015 and PERF102

.pre-commit-config.yaml

@@ -8,7 +8,7 @@ ci:
 
 repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.0.278
+    rev: v0.0.279
     hooks:
       - id: ruff
         args: [--fix]

pymatgen/analysis/adsorption.py

@@ -558,7 +558,7 @@ def substitute(site, i):
             props = self.slab.site_properties
             if sub_both_sides:
                 # Find an equivalent site on the other surface
-                eq_indices = [indices for indices in sym_slab.equivalent_indices if i in indices][0]
+                eq_indices = next(indices for indices in sym_slab.equivalent_indices if i in indices)
                 for ii in eq_indices:
                     if f"{sym_slab[ii].frac_coords[2]:.6f}" != f"{site.frac_coords[2]:.6f}":
                         props["surface_properties"][ii] = "substitute"

pymatgen/analysis/chemenv/connectivity/connected_components.py

@@ -665,7 +665,7 @@ def elastic_centered_graph(self, start_node=None):
         # Loop on start_nodes, sometimes some nodes cannot be elastically taken
         # inside the cell if you start from a specific node
         ntest_nodes = 0
-        start_node = list(self.graph.nodes())[0]
+        start_node = next(iter(self.graph.nodes()))
 
         ntest_nodes += 1
         centered_connected_subgraph = nx.MultiGraph()

pymatgen/analysis/chemenv/connectivity/tests/test_connected_components.py

@@ -872,7 +872,7 @@ def test_coordination_sequences(self):
         assert len(ccs_all) == 1
         cc_oct = ccs_oct[0]
         cc_all = ccs_all[0]
-        cc_oct_node = list(cc_oct.graph.nodes())[0]
+        cc_oct_node = next(iter(cc_oct.graph.nodes()))
         cseq = cc_oct.coordination_sequence(source_node=cc_oct_node, path_size=6)
         assert cseq == {1: 6, 2: 18, 3: 38, 4: 66, 5: 102, 6: 146}
         cc_all_oct_node = next(n for n in cc_all.graph.nodes() if n.coordination_environment == "O:6")

pymatgen/analysis/chemenv/utils/scripts_utils.py

@@ -123,7 +123,7 @@ def draw_cg(
             else:
                 faces = cg.faces(neighbors)
                 edges = cg.edges(neighbors)
-            symbol = list(site.species)[0].symbol
+            symbol = next(iter(site.species)).symbol
             if faces_color_override:
                 mycolor = faces_color_override
             else:
@@ -233,7 +233,7 @@ def compute_environments(chemenv_configuration):
                 source_type = questions[test]
         else:
             found = False
-            source_type = list(questions.values())[0]
+            source_type = next(iter(questions.values()))
         if found and len(questions) > 1:
             input_source = test
         if source_type == "cif":

pymatgen/analysis/dimensionality.py

@@ -129,7 +129,7 @@ def get_structure_components(
     components = []
     for graph in comp_graphs:
         dimensionality, vertices = calculate_dimensionality_of_site(
-            bonded_structure, list(graph.nodes())[0], inc_vertices=True
+            bonded_structure, next(iter(graph.nodes())), inc_vertices=True
         )
 
         component = {"dimensionality": dimensionality}
@@ -267,7 +267,7 @@ def zero_d_graph_to_molecule_graph(bonded_structure, graph):
     seen_indices = []
     sites = []
 
-    start_index = list(graph.nodes())[0]
+    start_index = next(iter(graph.nodes()))
     queue = [(start_index, (0, 0, 0), bonded_structure.structure[start_index])]
     while len(queue) > 0:
         comp_i, image_i, site_i = queue.pop(0)

pymatgen/analysis/graphs.py

@@ -401,7 +401,7 @@ def add_edge(
 
             # ensure that the first non-zero jimage index is positive
             # assumes that at least one non-zero index is present
-            is_positive = [idx for idx in to_jimage if idx != 0][0] > 0
+            is_positive = next(idx for idx in to_jimage if idx != 0) > 0
 
             if not is_positive:
                 # let's flip the jimage,

pymatgen/analysis/local_env.py

@@ -1459,15 +1459,15 @@ def get_nn_info(self, structure: Structure, n: int):
         siw = []
 
         # Get only the atom of interest
-        site_atom = [
+        site_atom = next(
             a
             for i, a in enumerate(openbabel.OBMolAtomDFSIter(obmol))
             if [a.GetX(), a.GetY(), a.GetZ()] == list(structure[n].coords)
-        ][0]
+        )
 
         for neighbor in openbabel.OBAtomAtomIter(site_atom):
             coords = [neighbor.GetX(), neighbor.GetY(), neighbor.GetZ()]
-            site = [a for a in structure if list(a.coords) == coords][0]
+            site = next(a for a in structure if list(a.coords) == coords)
             index = structure.index(site)
 
             bond = site_atom.GetBond(neighbor)

pymatgen/analysis/structure_prediction/dopant_predictor.py

@@ -45,8 +45,8 @@ def get_dopants_from_substitution_probabilities(structure, num_dopants=5, thresh
     subs = [
         {
             "probability": pred["probability"],
-            "dopant_species": list(pred["substitutions"])[0],
-            "original_species": list(pred["substitutions"].values())[0],
+            "dopant_species": next(iter(pred["substitutions"])),
+            "original_species": next(iter(pred["substitutions"].values())),
         }
         for species_preds in subs
         for pred in species_preds

pymatgen/analysis/surface_analysis.py

@@ -134,7 +134,7 @@ def __init__(
         self.label = label
         self.adsorbates = adsorbates if adsorbates else []
         self.clean_entry = clean_entry
-        self.ads_entries_dict = {str(list(ads.composition.as_dict())[0]): ads for ads in self.adsorbates}
+        self.ads_entries_dict = {str(next(iter(ads.composition.as_dict()))): ads for ads in self.adsorbates}
         self.mark = marker
         self.color = color
 
@@ -199,14 +199,14 @@ def surface_energy(self, ucell_entry, ref_entries=None):
         ucell_entry_comp = ucell_entry.composition.reduced_composition.as_dict()
         slab_clean_comp = Composition({el: slab_comp[el] for el in ucell_entry_comp})
         if slab_clean_comp.reduced_composition != ucell_entry.composition.reduced_composition:
-            list_els = [list(entry.composition.as_dict())[0] for entry in ref_entries]
+            list_els = [next(iter(entry.composition.as_dict())) for entry in ref_entries]
             if not any(el in list_els for el in ucell_entry.composition.as_dict()):
                 warnings.warn("Elemental references missing for the non-dopant species.")
 
         gamma = (Symbol("E_surf") - Symbol("Ebulk")) / (2 * Symbol("A"))
         ucell_comp = ucell_entry.composition
         ucell_reduced_comp = ucell_comp.reduced_composition
-        ref_entries_dict = {str(list(ref.composition.as_dict())[0]): ref for ref in ref_entries}
+        ref_entries_dict = {str(next(iter(ref.composition.as_dict()))): ref for ref in ref_entries}
         ref_entries_dict.update(self.ads_entries_dict)
 
         # Calculate Gibbs free energy of the bulk per unit formula
@@ -613,7 +613,7 @@ def area_frac_vs_chempot_plot(
         axes = plt.gca()
 
         for hkl in self.all_slab_entries:
-            clean_entry = list(self.all_slab_entries[hkl])[0]
+            clean_entry = next(iter(self.all_slab_entries[hkl]))
             # Ignore any facets that never show up on the
             # Wulff shape regardless of chemical potential
             if all(a == 0 for a in hkl_area_dict[hkl]):

pymatgen/analysis/tests/test_phase_diagram.py

@@ -374,7 +374,7 @@ def test_get_phase_separation_energy(self):
 
         duplicate_entry = PDEntry("Li2O", -14.31361175)
         scaled_dup_entry = PDEntry("Li4O2", -14.31361175 * 2)
-        stable_entry = [e for e in self.pd.stable_entries if e.name == "Li2O"][0]
+        stable_entry = next(e for e in self.pd.stable_entries if e.name == "Li2O")
 
         assert self.pd.get_phase_separation_energy(duplicate_entry) == self.pd.get_phase_separation_energy(
             stable_entry

pymatgen/analysis/tests/test_surface_analysis.py

@@ -104,7 +104,7 @@ def test_surface_energy(self):
             self.assert_all_close(float(se), manual_se, 10)
 
         # The (111) facet should be the most stable
-        clean111_entry = list(self.Cu_entry_dict[(1, 1, 1)])[0]
+        clean111_entry = next(iter(self.Cu_entry_dict[(1, 1, 1)]))
         se_Cu111 = clean111_entry.surface_energy(self.Cu_ucell_entry)
         assert min(all_se) == se_Cu111
 
@@ -212,19 +212,19 @@ def test_get_surface_equilibrium(self):
         # For clean stoichiometric system, the two equations should
         # be parallel because the surface energy is a constant. Then
         # get_surface_equilibrium should return None
-        clean111_entry = list(self.Cu_entry_dict[(1, 1, 1)])[0]
-        clean100_entry = list(self.Cu_entry_dict[(1, 0, 0)])[0]
+        clean111_entry = next(iter(self.Cu_entry_dict[(1, 1, 1)]))
+        clean100_entry = next(iter(self.Cu_entry_dict[(1, 0, 0)]))
         soln = self.Cu_analyzer.get_surface_equilibrium([clean111_entry, clean100_entry])
         assert not soln
 
         # For adsorbed system, we should find one intercept
         Pt_entries = self.metals_O_entry_dict["Pt"]
-        clean = list(Pt_entries[(1, 1, 1)])[0]
+        clean = next(iter(Pt_entries[(1, 1, 1)]))
         ads = Pt_entries[(1, 1, 1)][clean][0]
         Pt_analyzer = self.Oads_analyzer_dict["Pt"]
         soln = Pt_analyzer.get_surface_equilibrium([clean, ads])
 
-        assert list(soln.values())[0] != list(soln.values())[1]
+        assert next(iter(soln.values())) != list(soln.values())[1]
 
         # Check if the number of parameters for adsorption are correct
         assert (Symbol("delu_O"), Symbol("gamma")) == tuple(soln)
@@ -424,7 +424,7 @@ def load_O_adsorption():
         for el, val in metals_O_entry_dict.items():
             if el in k:
                 if "111" in k:
-                    clean = list(val[(1, 1, 1)])[0]
+                    clean = next(iter(val[(1, 1, 1)]))
                     ads = SlabEntry(
                         entry.structure,
                         entry.energy,
@@ -435,7 +435,7 @@ def load_O_adsorption():
                     )
                     metals_O_entry_dict[el][(1, 1, 1)][clean] = [ads]
                 if "110" in k:
-                    clean = list(val[(1, 1, 0)])[0]
+                    clean = next(iter(val[(1, 1, 0)]))
                     ads = SlabEntry(
                         entry.structure,
                         entry.energy,
@@ -446,7 +446,7 @@ def load_O_adsorption():
                     )
                     metals_O_entry_dict[el][(1, 1, 0)][clean] = [ads]
                 if "100" in k:
-                    clean = list(val[(1, 0, 0)])[0]
+                    clean = next(iter(val[(1, 0, 0)]))
                     ads = SlabEntry(
                         entry.structure,
                         entry.energy,

pymatgen/command_line/tests/test_critic2_caller.py

@@ -135,7 +135,7 @@ def test_properties_to_from_dict(self):
     def test_graph_output(self):
         sg = self.c2o.structure_graph()
         assert str(sg.structure[3].specie) == "Xbcp"
-        assert set(list(sg.graph.edges(data=True))[0][2]) == {
+        assert set(next(iter(sg.graph.edges(data=True)))[2]) == {
             "to_jimage",
             "weight",
             "field",

pymatgen/core/bonds.py

@@ -68,8 +68,8 @@ def get_bond_order(self, tol: float = 0.2, default_bl: float | None = None) -> f
             Float value of bond order. For example, for C-C bond in
             benzene, return 1.7.
         """
-        sp1 = list(self.site1.species)[0]
-        sp2 = list(self.site2.species)[0]
+        sp1 = next(iter(self.site1.species))
+        sp2 = next(iter(self.site2.species))
         dist = self.site1.distance(self.site2)
         return get_bond_order(sp1, sp2, dist, tol, default_bl)
 
@@ -93,8 +93,8 @@ def is_bonded(site1, site2, tol: float = 0.2, bond_order: float | None = None, d
         Returns:
             Boolean indicating whether two sites are bonded.
         """
-        sp1 = list(site1.species)[0]
-        sp2 = list(site2.species)[0]
+        sp1 = next(iter(site1.species))
+        sp2 = next(iter(site2.species))
         dist = site1.distance(site2)
         syms = tuple(sorted([sp1.symbol, sp2.symbol]))
         if syms in bond_lengths:

pymatgen/core/periodic_table.py

@@ -1266,7 +1266,7 @@ def get_shannon_radius(
         radii = self._el.data["Shannon radii"]
         radii = radii[str(int(self._oxi_state))][cn]  # type: ignore
         if len(radii) == 1:
-            key, data = list(radii.items())[0]
+            key, data = next(iter(radii.items()))
             if key != spin:
                 warnings.warn(
                     f"Specified {spin=} not consistent with database spin of {key}. "

pymatgen/core/sites.py

@@ -152,7 +152,7 @@ def distance_from_point(self, pt) -> float:
     def species_string(self) -> str:
         """String representation of species on the site."""
         if self.is_ordered:
-            return str(list(self.species)[0])
+            return str(next(iter(self.species)))
         sorted_species = sorted(self.species)
         return ", ".join(f"{sp}:{self.species[sp]:.3f}" for sp in sorted_species)
 
@@ -170,7 +170,7 @@ def specie(self) -> Element | Species | DummySpecies:
         """
         if not self.is_ordered:
             raise AttributeError("specie property only works for ordered sites!")
-        return list(self.species)[0]
+        return next(iter(self.species))
 
     @property
     def is_ordered(self) -> bool:

pymatgen/core/structure.py

@@ -2157,7 +2157,7 @@ def interpolate(
 
             if len(unmapped_start_ind) == 1:
                 i = unmapped_start_ind[0]
-                j = list(set(range(len(start_coords))) - set(matched))[0]  # type: ignore
+                j = next(iter(set(range(len(start_coords))) - set(matched)))  # type: ignore
                 sorted_end_coords[i] = end_coords[j]
 
             end_coords = sorted_end_coords

pymatgen/core/tensors.py

@@ -453,7 +453,7 @@ def get_ieee_rotation(structure, refine_rotation=True):
             n_umask = np.logical_not(angles == angles[u_index])
             rotation[1] = get_uvec(vecs[u_index])
             # Shorter of remaining lattice vectors for c axis
-            c = [vec / mag for (mag, vec) in sorted(zip(lengths[n_umask], vecs[n_umask]))][0]
+            c = next(vec / mag for (mag, vec) in sorted(zip(lengths[n_umask], vecs[n_umask])))
             rotation[2] = np.array(c)
             rotation[0] = np.cross(rotation[1], rotation[2])
 

pymatgen/electronic_structure/bandstructure.py

@@ -635,7 +635,7 @@ def from_dict(cls, dct):
         labels_dict = {k.strip(): v for k, v in dct["labels_dict"].items()}
         projections = {}
         structure = None
-        if isinstance(list(dct["bands"].values())[0], dict):
+        if isinstance(next(iter(dct["bands"].values())), dict):
             eigenvals = {Spin(int(k)): np.array(dct["bands"][k]["data"]) for k in dct["bands"]}
         else:
             eigenvals = {Spin(int(k)): dct["bands"][k] for k in dct["bands"]}

pymatgen/electronic_structure/boltztrap.py

@@ -927,7 +927,7 @@ def check_acc_bzt_bands(sbs_bz, sbs_ref, warn_thr=(0.03, 0.03)):
         else:
             bnd_around_efermi = []
             delta = 0
-            spin = list(sbs_bz.bands)[0]
+            spin = next(iter(sbs_bz.bands))
             while len(bnd_around_efermi) < 8 and delta < 100:
                 delta += 0.1
                 bnd_around_efermi = []
@@ -1605,13 +1605,13 @@ def get_complete_dos(self, structure: Structure, analyzer_for_second_spin=None):
             cdos=an_up.get_complete_dos(bs.structure,an_dw)
         """
         pdoss: dict[PeriodicSite, dict[Orbital, dict[Spin, ArrayLike]]] = {}
-        spin_1 = list(self.dos.densities)[0]
+        spin_1 = next(iter(self.dos.densities))
 
         if analyzer_for_second_spin:
             if not np.all(self.dos.energies == analyzer_for_second_spin.dos.energies):
                 raise BoltztrapError("Dos merging error: energies of the two dos are different")
 
-            spin_2 = list(analyzer_for_second_spin.dos.densities)[0]
+            spin_2 = next(iter(analyzer_for_second_spin.dos.densities))
             if spin_1 == spin_2:
                 raise BoltztrapError("Dos merging error: spin component are the same")
 

pymatgen/electronic_structure/boltztrap2.py

@@ -320,11 +320,11 @@ def __init__(self, vrun_obj=None):
             self.atoms = AseAtomsAdaptor.get_atoms(self.structure)
             self.proj = None
             if len(vrun_obj.eigenvalues) == 1:
-                e = list(vrun_obj.eigenvalues.values())[0]
+                e = next(iter(vrun_obj.eigenvalues.values()))
                 self.ebands = e[:, :, 0].transpose() * units.eV
                 self.dosweight = 2.0
                 if vrun_obj.projected_eigenvalues:
-                    self.proj = list(vrun_obj.projected_eigenvalues.values())[0]
+                    self.proj = next(iter(vrun_obj.projected_eigenvalues.values()))
 
             elif len(vrun_obj.eigenvalues) == 2:
                 raise BoltztrapError("spin bs case not implemented")

pymatgen/electronic_structure/plotter.py

@@ -617,7 +617,7 @@ def get_plot(
         handles = []
         vbm_min, cbm_max = [], []
 
-        colors = list(plt.rcParams["axes.prop_cycle"].by_key().values())[0]
+        colors = next(iter(plt.rcParams["axes.prop_cycle"].by_key().values()))
         for ibs, bs in enumerate(self._bs):
             # set first bs in the list as ref for rescaling the distances of the other bands
             bs_ref = self._bs[0] if len(self._bs) > 1 and ibs > 0 else None
@@ -1871,7 +1871,7 @@ def _number_of_subfigures(self, dictio, dictpa, sum_atoms, sum_morbs):
                     _sites = self._bs.structure.sites
                     indices = []
                     for i in range(0, len(_sites)):  # pylint: disable=C0200
-                        if list(_sites[i]._species)[0] == Element(elt):
+                        if next(iter(_sites[i]._species)) == Element(elt):
                             indices.append(i + 1)
                     for number in dictpa[elt]:
                         if isinstance(number, str):
@@ -1918,7 +1918,7 @@ def _number_of_subfigures(self, dictio, dictpa, sum_atoms, sum_morbs):
                         _sites = self._bs.structure.sites
                         indices = []
                         for i in range(0, len(_sites)):  # pylint: disable=C0200
-                            if list(_sites[i]._species)[0] == Element(elt):
+                            if next(iter(_sites[i]._species)) == Element(elt):
                                 indices.append(i + 1)
                         for number in sum_atoms[elt]:
                             if isinstance(number, str):
@@ -2042,7 +2042,7 @@ def orbital_label(list_orbitals):
                     _sites = self._bs.structure.sites
                     indices = []
                     for i in range(0, len(_sites)):  # pylint: disable=C0200
-                        if list(_sites[i]._species)[0] == Element(elt):
+                        if next(iter(_sites[i]._species)) == Element(elt):
                             indices.append(i + 1)
                     flag_1 = len(set(dictpa[elt]).intersection(indices))
                     flag_2 = len(set(sum_atoms[elt]).intersection(indices))
@@ -2091,7 +2091,7 @@ def orbital_label(list_orbitals):
                     _sites = self._bs.structure.sites
                     indices = []
                     for i in range(0, len(_sites)):  # pylint: disable=C0200
-                        if list(_sites[i]._species)[0] == Element(elt):
+                        if next(iter(_sites[i]._species)) == Element(elt):
                             indices.append(i + 1)
                     flag_1 = len(set(dictpa[elt]).intersection(indices))
                     flag_2 = len(set(sum_atoms[elt]).intersection(indices))