Add tests to validate function overload matching

tests/test_demangler.py

@@ -1,5 +1,8 @@
 #!/usr/bin/python3
 
+import itertools
+from typing import Iterable
+
 import itanium_demangler as dm
 import pytest
 import smgdc.demangler_helpers as dh
@@ -90,3 +93,42 @@ def test_function_in_virtual_class(input_vtsym: str, input_fnsym: str, expected:
 def test_function_match_signature(fnsym_a: str, fnsym_b: str, expected: bool):
     sig_a, sig_b = map(dh.extract_method_signature, map(dm.parse, (fnsym_a, fnsym_b)))
     assert expected == (sig_a == sig_b)
+
+
+@pytest.mark.parametrize(
+    "fnsyms,expected",
+    [
+        (
+            # PASS: same class, same name, differing parameter types
+            (
+                "_ZN11CBaseEntity8KeyValueEPKcS1_",
+                "_ZN11CBaseEntity8KeyValueEPKcf",
+                "_ZN11CBaseEntity8KeyValueEPKcRK6Vector",
+            ),
+            True,
+        ),
+        (
+            # PASS: same class, same name, differing parameter types
+            (
+                "_ZN24CTFWeaponBaseGrenadeProj11InitGrenadeERK6VectorS2_P20CBaseCombatCharacterRK13CTFWeaponInfo",
+                "_ZN24CTFWeaponBaseGrenadeProj11InitGrenadeERK6VectorS2_P20CBaseCombatCharacterif",
+            ),
+            True,
+        ),
+        (
+            # PASS: different class, same name, differing parameter types
+            (
+                "_ZN20CBaseCombatCharacter8FVisibleEP11CBaseEntityiPS1_",
+                "_ZN11CBaseEntity8FVisibleERK6VectoriPPS_",
+            ),
+            True,
+        ),
+    ],
+)
+def test_function_overloaded(fnsyms: Iterable[str], expected: bool):
+    """
+    Tests that all the given symbols are overloads of the same name.
+    Of course, this is only inference based on symbol name.
+    """
+    node_syms = map(dh.extract_method_fname, map(dm.parse, fnsyms))
+    assert all(a == b for a, b in itertools.permutations(node_syms, 2))