Add hash function to URLDependency

This will enable URLDependency to compute the hash for the file at the
temporary path. The temporary path should be the path to the downloaded
file from `URLDependency.url`.

src/poetry/core/packages/url_dependency.py

@@ -1,11 +1,19 @@
 from __future__ import annotations
 
+import hashlib
+import io
+
+from typing import TYPE_CHECKING
 from typing import Iterable
 from urllib.parse import urlparse
 
 from poetry.core.packages.dependency import Dependency
 
 
+if TYPE_CHECKING:
+    from pathlib import Path
+
+
 class URLDependency(Dependency):
     def __init__(
         self,
@@ -44,6 +52,14 @@ def url(self) -> str:
     def directory(self) -> str | None:
         return self._directory
 
+    def hash(self, temp_path: Path, hash_name: str = "sha256") -> str:
+        h = hashlib.new(hash_name)
+        with temp_path.open("rb") as fp:
+            for content in iter(lambda: fp.read(io.DEFAULT_BUFFER_SIZE), b""):
+                h.update(content)
+
+        return h.hexdigest()
+
     @property
     def base_pep_508_name(self) -> str:
         requirement = self.pretty_name