specification: make is_same_package_as() commutative and …

src/poetry/core/packages/specification.py

@@ -75,9 +75,10 @@ def is_same_package_as(self, other: PackageSpecification) -> bool:
         if other.complete_name != self.complete_name:
             return False
 
+        if self._source_type != other.source_type:
+            return False
+
         if self._source_type:
-            if self._source_type != other.source_type:
-                return False
 
             if (
                 self._source_url or other.source_url

tests/packages/test_specification.py

@@ -0,0 +1,23 @@
+from __future__ import annotations
+
+import pytest
+
+from poetry.core.packages.specification import PackageSpecification
+
+
+@pytest.mark.parametrize(
+    "spec1, spec2, expected",
+    [
+        (PackageSpecification("a"), PackageSpecification("a"), True),
+        (PackageSpecification("a", "type1"), PackageSpecification("a", "type1"), True),
+        (PackageSpecification("a", "type1"), PackageSpecification("a", "type2"), False),
+        (PackageSpecification("a"), PackageSpecification("a", "type1"), False),
+        (PackageSpecification("a", "type1"), PackageSpecification("a"), False),
+    ],
+)
+def test_is_same_package_source_type(
+    spec1: PackageSpecification,
+    spec2: PackageSpecification,
+    expected: bool,
+) -> None:
+    assert spec1.is_same_package_as(spec2) == expected