Replace UnsupportedAlgorithmError with ValueError

UnsupportedAlgorithmError is a securesystemslib exception that is
reexported inside tuf/api/exceptions.py
It's only used once inside "Targetfile.from_data()" and there it's used
to denote that there is a problem with the given argument.
That's why this error can be replaced with "ValueError" and we can
stop reexporting it from securesystemslib.

Signed-off-by: Martin Vrachev <[email protected]>

Author: MVrachev

tuf/api/exceptions.py

@@ -8,13 +8,6 @@
 """
 
 
-#### General errors ####
-
-# Reexport securesystemslib exceptions so that users of code that throws them
-# doesn't have to import securesystemslib to handle them.
-# pylint: disable=unused-import
-from securesystemslib.exceptions import UnsupportedAlgorithmError
-
 #### MetadataError errors ####
 
 

tuf/api/metadata.py

@@ -1316,8 +1316,8 @@ def from_file(
                 specified the securesystemslib default hash algorithm is used.
         Raises:
             FileNotFoundError: The file doesn't exist.
-            UnsupportedAlgorithmError: The hash algorithms list
-                contains an unsupported algorithm.
+            ValueError: The hash algorithms list contains an unsupported
+                algorithm.
         """
         with open(local_path, "rb") as file:
             return cls.from_data(target_file_path, file, hash_algorithms)
@@ -1339,8 +1339,8 @@ def from_data(
                 specified the securesystemslib default hash algorithm is used.
 
         Raises:
-            UnsupportedAlgorithmError: The hash algorithms list
-                contains an unsupported algorithm.
+            ValueError: The hash algorithms list contains an unsupported
+                algorithm.
         """
         if isinstance(data, bytes):
             length = len(data)
@@ -1366,9 +1366,7 @@ def from_data(
                 sslib_exceptions.UnsupportedAlgorithmError,
                 sslib_exceptions.FormatError,
             ) as e:
-                raise exceptions.UnsupportedAlgorithmError(
-                    f"Unsupported algorithm '{algorithm}'"
-                ) from e
+                raise ValueError(f"Unsupported algorithm '{algorithm}'") from e
 
             hashes[algorithm] = digest_object.hexdigest()