Add function to check hashes against known digests

Author: sbidoul

src/pip/_internal/utils/hashes.py

@@ -105,6 +105,13 @@ def check_against_path(self, path: str) -> None:
         with open(path, "rb") as file:
             return self.check_against_file(file)
 
+    def has_one_of(self, hashes: Dict[str, str]) -> bool:
+        """Return whether any of the given hashes are allowed."""
+        for hash_name, hex_digest in hashes.items():
+            if self.is_hash_allowed(hash_name, hex_digest):
+                return True
+        return False
+
     def __bool__(self) -> bool:
         """Return whether I know any known-good hashes."""
         return bool(self._allowed)

tests/unit/test_utils.py

@@ -425,6 +425,14 @@ def test_hash(self) -> None:
         cache[Hashes({"sha256": ["ab", "cd"]})] = 42
         assert cache[Hashes({"sha256": ["ab", "cd"]})] == 42
 
+    def test_has_one_of(self) -> None:
+        hashes = Hashes({"sha256": ["abcd", "efgh"], "sha384": ["ijkl"]})
+        assert hashes.has_one_of({"sha256": "abcd"})
+        assert hashes.has_one_of({"sha256": "efgh"})
+        assert not hashes.has_one_of({"sha256": "xyzt"})
+        empty_hashes = Hashes()
+        assert not empty_hashes.has_one_of({"sha256": "xyzt"})
+
 
 class TestEncoding:
     """Tests for pip._internal.utils.encoding"""