fix hashing for custom classes

CHANGELOG.md

@@ -1,5 +1,9 @@
 ## Changelog
 
+### [2.6.0] - 2022-08-
+#### Fixed
+- fix hashing for custom classes
+
 ### [2.5.0] - 2022-08-14
 #### Added
 - added support for KeyboardInterrupt in processor module

src/rapidfuzz/cpp_common.pxd

@@ -238,11 +238,6 @@ cdef extern from "cpp_common.hpp":
     RF_String convert_string(object py_str)
     void validate_string(object py_str, const char* err) except +
 
-cdef inline uint64_t rf_hash(val) except *:
-    if val == -1:
-        return <uint64_t>-1
-    return <uint64_t>hash(val)
-
 cdef inline RF_String hash_array(arr) except *:
     # TODO on Cpython this does not require any copies
     cdef RF_String s_proc
@@ -283,7 +278,7 @@ cdef inline RF_String hash_array(arr) except *:
         else: # float/double are hashed
             s_proc.kind = RF_StringType.RF_UINT64
             for i in range(s_proc.length):
-                (<uint64_t*>s_proc.data)[i] = rf_hash(arr[i])
+                (<uint64_t*>s_proc.data)[i] = <uint64_t>hash(arr[i])
     except Exception as e:
         free(s_proc.data)
         s_proc.data = NULL
@@ -309,8 +304,10 @@ cdef inline RF_String hash_sequence(seq) except *:
             # this is required so e.g. a list of char can be compared to a string
             if isinstance(elem, str) and len(elem) == 1:
                 (<uint64_t*>s_proc.data)[i] = <uint64_t><Py_UCS4>elem
+            elif isinstance(elem, int) and elem == -1:
+                (<uint64_t*>s_proc.data)[i] = <uint64_t>-1
             else:
-                (<uint64_t*>s_proc.data)[i] = rf_hash(elem)
+                (<uint64_t*>s_proc.data)[i] = <uint64_t>hash(elem)
     except Exception as e:
         free(s_proc.data)
         s_proc.data = NULL

tests/distance/test_Levenshtein.py

@@ -10,6 +10,18 @@ from rapidfuzz.distance import Opcodes, Opcode, Levenshtein_cpp, Levenshtein_py
 def isclose(a, b, rel_tol=1e-09, abs_tol=0.0):
     return abs(a - b) <= max(rel_tol * max(abs(a), abs(b)), abs_tol)
 
+class CustomHashable:
+    def __init__(self, string):
+        self._string = string
+
+    def __eq__(self, other):
+        raise NotImplementedError
+
+    def __ne__(self, other):
+        return not self.__eq__(other)
+
+    def __hash__(self):
+        return hash(self._string)
 
 class Levenshtein:
     @staticmethod
@@ -61,6 +73,7 @@ def test_cross_type_matching():
     # todo add support in pure python
     assert Levenshtein_cpp.distance("aaaa", [ord("a"), ord("a"), "a", "a"]) == 0
     assert Levenshtein_cpp.distance([0, -1], [0, -2]) == 1
+    assert Levenshtein_cpp.distance([CustomHashable("aa"), CustomHashable("aa")], [CustomHashable("aa"), CustomHashable("bb")]) == 1
 
 
 def test_word_error_rate():