style: enable B904

backend/find_tensorflow.py

@@ -102,7 +102,7 @@ def find_tensorflow() -> Tuple[Optional[str], List[str]]:
                 )
                 tf_version = "2.14.1"
             else:
-                raise RuntimeError("Unsupported CUDA version")
+                raise RuntimeError("Unsupported CUDA version") from None
         requires.extend(get_tf_requirement(tf_version)["cpu"])
         # setuptools will re-find tensorflow after installing setup_requires
         tf_install_dir = None

deepmd/dpmodel/descriptor/descriptor.py

@@ -39,8 +39,10 @@ def __new__(cls, *args, **kwargs):
         if cls is DescriptorBlock:
             try:
                 descrpt_type = kwargs["type"]
-            except KeyError:
-                raise KeyError("the type of DescriptorBlock should be set by `type`")
+            except KeyError as e:
+                raise KeyError(
+                    "the type of DescriptorBlock should be set by `type`"
+                ) from e
             cls = cls.get_class_by_type(descrpt_type)
         return super().__new__(cls)
 

deepmd/entrypoints/neighbor_stat.py

@@ -75,8 +75,8 @@ def neighbor_stat(
     backends = Backend.get_backends_by_feature(Backend.Feature.NEIGHBOR_STAT)
     try:
         backend_obj = backends[backend]()
-    except KeyError:
-        raise ValueError(f"Invalid backend {backend}")
+    except KeyError as e:
+        raise ValueError(f"Invalid backend {backend}") from e
     NeighborStat = backend_obj.neighbor_stat
     all_sys = expand_sys_str(system)
     if not len(all_sys):

deepmd/pt/model/descriptor/descriptor.py

@@ -48,8 +48,10 @@ def __new__(cls, *args, **kwargs):
         if cls is DescriptorBlock:
             try:
                 descrpt_type = kwargs["type"]
-            except KeyError:
-                raise KeyError("the type of DescriptorBlock should be set by `type`")
+            except KeyError as e:
+                raise KeyError(
+                    "the type of DescriptorBlock should be set by `type`"
+                ) from e
             cls = cls.get_class_by_type(descrpt_type)
         return super().__new__(cls)
 

deepmd/utils/data_system.py

@@ -196,8 +196,8 @@ def __init__(
             words = self.test_size.split("%")
             try:
                 percent = int(words[0])
-            except ValueError:
-                raise RuntimeError("unknown test_size rule " + words[0])
+            except ValueError as e:
+                raise RuntimeError("unknown test_size rule " + words[0]) from e
             self.test_size = self._make_auto_ts(percent)
         elif isinstance(self.test_size, list):
             pass

pyproject.toml

@@ -344,6 +344,7 @@ select = [
     "TID251", # banned-api
     "TID253", # banned-module-level-imports
     "T20", # ban print
+    "B904", # raise-without-from-inside-except
 ]
 
 ignore = [

source/tests/common/test_argument_parser.py

@@ -157,13 +157,13 @@ def run_test(self, *, command: str, mapping: "TEST_DICT"):
         try:
             with redirect_stderr(buffer):
                 namespace = parse_args(cmd_args)
-        except SystemExit:
+        except SystemExit as e:
             raise SystemExit(
                 f"Encountered expection when parsing arguments ->\n\n"
                 f"{buffer.getvalue()}\n"
                 f"passed in arguments were: {cmd_args}\n"
                 f"built from dict {mapping}"
-            )
+            ) from e
         self.attr_and_type_check(namespace, mapping, command, test_value=True)
 
         # check for required arguments
@@ -189,13 +189,13 @@ def run_test(self, *, command: str, mapping: "TEST_DICT"):
         try:
             with redirect_stderr(buffer):
                 namespace = parse_args(cmd_args)
-        except SystemExit:
+        except SystemExit as e:
             raise SystemExit(
                 f"Encountered expection when parsing DEFAULT arguments ->\n\n"
                 f"{buffer.getvalue()}\n"
                 f"passed in arguments were: {cmd_args}\n"
                 f"built from dict {mapping}"
-            )
+            ) from e
         self.attr_and_type_check(namespace, mapping, command, test_value=False)
 
     def test_no_command(self):

source/tests/tf/test_parallel_training.py

@@ -16,10 +16,10 @@ class TestSingleMachine(unittest.TestCase):
     def setUp(self):
         try:
             import horovod  # noqa: F401
-        except ImportError:
+        except ImportError as e:
             raise unittest.SkipTest(
                 "Package horovod is required for parallel-training tests."
-            )
+            ) from e
         self.input_file = str(tests_path / "model_compression" / "input.json")
 
     def test_two_workers(self):