Fix errors from running ruff check

pkcs11/exceptions.py

@@ -61,7 +61,7 @@ class DataInvalid(PKCS11Error):
 class DataLenRange(PKCS11Error):
     """
     The plaintext input data to a cryptographic operation has a bad length.
-    Depending on the operation’s mechanism, this could mean that the plaintext
+    Depending on the operation's mechanism, this could mean that the plaintext
     data is too short, too long, or is not a multiple of some particular block
     size.
     """
@@ -103,7 +103,7 @@ class EncryptedDataLenRange(PKCS11Error):
     """
     The ciphertext input to a decryption operation has been determined to be
     invalid ciphertext solely on the basis of its length.  Depending on the
-    operation’s mechanism, this could mean that the ciphertext is too short,
+    operation's mechanism, this could mean that the ciphertext is too short,
     too long, or is not a multiple of some particular block size.
     """
 
@@ -232,7 +232,7 @@ class OperationActive(PKCS11Error):
     activating an encryption operation with C_EncryptInit.  Or, an active
     digesting operation and an active encryption operation would prevent
     Cryptoki from activating a signature operation.  Or, on a token which
-    doesn’t support simultaneous dual cryptographic operations in a session
+    doesn't support simultaneous dual cryptographic operations in a session
     (see the description of the CKF_DUAL_CRYPTO_OPERATIONS flag in the
     CK_TOKEN_INFO structure), an active signature operation would prevent
     Cryptoki from activating an encryption operation.

pkcs11/types.py

@@ -322,8 +322,8 @@ def get_key(self, object_class=None, key_type=None, label=None, id=None):
         try:
             try:
                 key = next(iterator)
-            except StopIteration:
-                raise NoSuchKey("No key matching %s" % attrs)
+            except StopIteration as ex:
+                raise NoSuchKey("No key matching %s" % attrs) from ex
 
             try:
                 next(iterator)
@@ -645,8 +645,8 @@ def __getitem__(self, key):
         if self._handle is None:
             try:
                 return self.params[key]
-            except KeyError:
-                raise AttributeTypeInvalid
+            except KeyError as ex:
+                raise AttributeTypeInvalid from ex
         else:
             return super().__getitem__(key)
 

tests/__init__.py

@@ -20,27 +20,30 @@
 
 try:
     LIB = os.environ["PKCS11_MODULE"]
-except KeyError:
-    raise RuntimeError("Must define `PKCS11_MODULE' to run tests.")
+except KeyError as ex:
+    raise RuntimeError("Must define `PKCS11_MODULE' to run tests.") from ex
 
 
 try:
     TOKEN = os.environ["PKCS11_TOKEN_LABEL"]
-except KeyError:
-    raise RuntimeError("Must define `PKCS11_TOKEN_LABEL' to run tests.")
+except KeyError as ex:
+    raise RuntimeError("Must define `PKCS11_TOKEN_LABEL' to run tests.") from ex
 
 TOKEN_PIN = os.environ.get("PKCS11_TOKEN_PIN")  # Can be None
 if TOKEN_PIN is None:
-    warn("`PKCS11_TOKEN_PIN' env variable is unset.")
+    warn("`PKCS11_TOKEN_PIN' env variable is unset.", stacklevel=2)
 
 TOKEN_SO_PIN = os.environ.get("PKCS11_TOKEN_SO_PIN")
 if TOKEN_SO_PIN is None:
     TOKEN_SO_PIN = TOKEN_PIN
-    warn("`PKCS11_TOKEN_SO_PIN' env variable is unset. Using value from `PKCS11_TOKEN_PIN'")
+    warn(
+        "`PKCS11_TOKEN_SO_PIN' env variable is unset. Using value from `PKCS11_TOKEN_PIN'",
+        stacklevel=2,
+    )
 
 OPENSSL = shutil.which("openssl", path=os.environ.get("OPENSSL_PATH"))
 if OPENSSL is None:
-    warn("Path to OpenSSL not found. Please adjust `PATH' or define `OPENSSL_PATH'")
+    warn("Path to OpenSSL not found. Please adjust `PATH' or define `OPENSSL_PATH'", stacklevel=2)
 
 
 class TestCase(unittest.TestCase):