Refactor progress

Author: brunorijsman

common/fragment.py

@@ -159,7 +159,13 @@ def from_enc_str(
         except ValueError as exc:
             raise InvalidBlockUUIDError(block_uuid=block_uuid_str) from exc
         block = pool.get_block(block_uuid)
-        start_byte = int(start_byte_str)
-        size = int(size_str)
-        data = block.take_data(start_byte, size)
-        return Fragment(block=block, start=start_byte, size=size, data=data)
+        try:
+            start = int(start_byte_str)
+        except ValueError as exc:
+            raise InvalidEncodedFragment(encoded_fragment=enc_str) from exc
+        try:
+            size = int(size_str)
+        except ValueError as exc:
+            raise InvalidEncodedFragment(encoded_fragment=enc_str) from exc
+        data = block.take_data(start, size)
+        return Fragment(block=block, start=start, size=size, data=data)

common/tests/test_fragment.py

@@ -5,7 +5,7 @@
 from uuid import uuid4
 import pytest
 from common.block import Block
-from common.exceptions import InvalidBlockUUIDError
+from common.exceptions import InvalidBlockUUIDError, InvalidEncodedFragment
 from common.fragment import APIFragment, Fragment
 from common.pool import Pool
 from common.utils import bytes_to_str
@@ -196,6 +196,26 @@ def test_from_enc_str_success():
     assert block._data == bytes.fromhex("00000000000506070809")
 
 
+def test_from_enc_str_bad_str():
+    """
+    Attempt to create a Fragment from a bad encoded string (invalid encoded string format).
+    """
+    # pylint: disable=protected-access
+    (pool, block) = _create_test_pool_and_block(10)
+    # No colons
+    with pytest.raises(InvalidEncodedFragment):
+        _fragment = Fragment.from_enc_str("not-an-encoded-str", pool)
+    # Only one colon
+    with pytest.raises(InvalidEncodedFragment):
+        _fragment = Fragment.from_enc_str(f"{block.uuid}:only-one-colon", pool)
+    # Start is not a number
+    with pytest.raises(InvalidEncodedFragment):
+        _fragment = Fragment.from_enc_str(f"{block.uuid}:not-a-number:5", pool)
+    # Size is not a number
+    with pytest.raises(InvalidEncodedFragment):
+        _fragment = Fragment.from_enc_str(f"{block.uuid}:0:not-a-number", pool)
+
+
 def test_from_enc_str_bad_block_uuid():
     """
     Attempt to create a Fragment from a bad encoded string (invalid block UUID).