Moved CRC32CHash into own private module

This leaves the __init__ module fairly logic-free.

Signed-off-by: Rodrigo Tobar <[email protected]>

src/crc32c/__init__.py

@@ -1,87 +1,6 @@
-from __future__ import annotations
-
-from typing import TYPE_CHECKING
-
 # Explicitly "import ... as" to make mypy --strict happy
 from ._crc32c import big_endian as big_endian
 from ._crc32c import crc32 as crc32
 from ._crc32c import crc32c as crc32c
 from ._crc32c import hardware_based as hardware_based
-
-if TYPE_CHECKING:
-    from typing_extensions import Buffer, Self
-
-
-class CRC32CHash:
-    """Wrapper class for crc32c. Tries to conform to the interface of `hashlib` classes."""
-
-    @property
-    def digest_size(self) -> int:
-        """
-        The size of the resulting hash in bytes.
-        """
-        return 4
-
-    @property
-    def block_size(self) -> int:
-        """
-        The internal block size of the hash algorithm in bytes.
-        """
-        return 1
-
-    @property
-    def name(self) -> str:
-        """
-        The canonical name of this hash,
-        """
-        return "crc32c"
-
-    @property
-    def checksum(self) -> int:
-        """
-        The checksum calculated so far. Not part of the hashlib interface.
-        """
-        return self._checksum
-
-    def __init__(self, data: Buffer = b"", gil_release_mode: int = -1) -> None:
-        """
-        Initialise the hash object with an optional bytes-like object.
-        Uses the given GIL release mode on each checksum calculation.
-        """
-        self._checksum = crc32c(data, gil_release_mode=gil_release_mode)
-        self._gil_release_mode = gil_release_mode
-
-    def update(self, data: Buffer) -> None:
-        """
-        Update the hash object with the bytes-like object.
-        Repeated calls are equivalent to a single call with the concatenation of all the arguments:
-        m.update(a); m.update(b) is equivalent to m.update(a+b).
-        """
-        self._checksum = crc32c(
-            data, self._checksum, gil_release_mode=self._gil_release_mode
-        )
-
-    def digest(self) -> bytes:
-        """
-        Return the digest of the data passed to the update() method so far.
-        This is a bytes object of size digest_size which may contain bytes in the whole range from 0 to 255.
-        """
-        return self._checksum.to_bytes(4, "big")
-
-    def hexdigest(self) -> str:
-        """
-        Like digest() except the digest is returned as a string object of double length,
-        containing only hexadecimal digits.
-        This may be used to exchange the value safely in email or other non-binary environments.
-        """
-        return self.digest().hex()
-
-    def copy(self) -> Self:
-        """
-        Return a copy (“clone”) of the hash object. This can be used to efficiently compute
-        the digests of data sharing a common initial substring.
-        """
-        res = type(self)()
-        res._checksum = self._checksum
-        res._gil_release_mode = self._gil_release_mode
-        return res
+from ._crc32hash import CRC32CHash as CRC32CHash

src/crc32c/_crc32hash.py

@@ -0,0 +1,83 @@
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+from ._crc32c import crc32c
+
+if TYPE_CHECKING:
+    from typing_extensions import Buffer, Self
+
+
+class CRC32CHash:
+    """Wrapper class for crc32c. Tries to conform to the interface of `hashlib` classes."""
+
+    @property
+    def digest_size(self) -> int:
+        """
+        The size of the resulting hash in bytes.
+        """
+        return 4
+
+    @property
+    def block_size(self) -> int:
+        """
+        The internal block size of the hash algorithm in bytes.
+        """
+        return 1
+
+    @property
+    def name(self) -> str:
+        """
+        The canonical name of this hash,
+        """
+        return "crc32c"
+
+    @property
+    def checksum(self) -> int:
+        """
+        The checksum calculated so far. Not part of the hashlib interface.
+        """
+        return self._checksum
+
+    def __init__(self, data: Buffer = b"", gil_release_mode: int = -1) -> None:
+        """
+        Initialise the hash object with an optional bytes-like object.
+        Uses the given GIL release mode on each checksum calculation.
+        """
+        self._checksum = crc32c(data, gil_release_mode=gil_release_mode)
+        self._gil_release_mode = gil_release_mode
+
+    def update(self, data: Buffer) -> None:
+        """
+        Update the hash object with the bytes-like object.
+        Repeated calls are equivalent to a single call with the concatenation of all the arguments:
+        m.update(a); m.update(b) is equivalent to m.update(a+b).
+        """
+        self._checksum = crc32c(
+            data, self._checksum, gil_release_mode=self._gil_release_mode
+        )
+
+    def digest(self) -> bytes:
+        """
+        Return the digest of the data passed to the update() method so far.
+        This is a bytes object of size digest_size which may contain bytes in the whole range from 0 to 255.
+        """
+        return self._checksum.to_bytes(4, "big")
+
+    def hexdigest(self) -> str:
+        """
+        Like digest() except the digest is returned as a string object of double length,
+        containing only hexadecimal digits.
+        This may be used to exchange the value safely in email or other non-binary environments.
+        """
+        return self.digest().hex()
+
+    def copy(self) -> Self:
+        """
+        Return a copy (“clone”) of the hash object. This can be used to efficiently compute
+        the digests of data sharing a common initial substring.
+        """
+        res = type(self)()
+        res._checksum = self._checksum
+        res._gil_release_mode = self._gil_release_mode
+        return res