python: use nodeid in error messages instead of function name

The function name is ambiguous, full nodeid is more helpful.

Author: bluetech

src/_pytest/python.py

@@ -870,7 +870,6 @@ class IdMaker:
     __slots__ = (
         "argnames",
         "config",
-        "func_name",
         "idfn",
         "ids",
         "nodeid",
@@ -893,9 +892,6 @@ class IdMaker:
     # Optionally, the ID of the node being parametrized.
     # Used only for clearer error messages.
     nodeid: str | None
-    # Optionally, the ID of the function being parametrized.
-    # Used only for clearer error messages.
-    func_name: str | None
 
     def make_unique_parameterset_ids(self) -> list[str | _HiddenParam]:
         """Make a unique identifier for each ParameterSet, that may be used to
@@ -1083,9 +1079,7 @@ def _complain_multiple_hidden_parameter_sets(self) -> NoReturn:
         )
 
     def _make_error_prefix(self) -> str:
-        if self.func_name is not None:
-            return f"In {self.func_name}: "
-        elif self.nodeid is not None:
+        if self.nodeid is not None:
             return f"In {self.nodeid}: "
         else:
             return ""
@@ -1435,23 +1429,21 @@ def _resolve_parameter_set_ids(
             ids_ = None
         else:
             idfn = None
-            ids_ = self._validate_ids(ids, parametersets, self.function.__name__)
+            ids_ = self._validate_ids(ids, parametersets)
         id_maker = IdMaker(
             argnames,
             parametersets,
             idfn,
             ids_,
             self.config,
             nodeid=nodeid,
-            func_name=self.function.__name__,
         )
         return id_maker.make_unique_parameterset_ids()
 
     def _validate_ids(
         self,
         ids: Iterable[object | None],
         parametersets: Sequence[ParameterSet],
-        func_name: str,
     ) -> list[object | None]:
         try:
             num_ids = len(ids)  # type: ignore[arg-type]
@@ -1464,8 +1456,11 @@ def _validate_ids(
 
         # num_ids == 0 is a special case: https://github.com/pytest-dev/pytest/issues/1849
         if num_ids != len(parametersets) and num_ids != 0:
-            msg = "In {}: {} parameter sets specified, with different number of ids: {}"
-            fail(msg.format(func_name, len(parametersets), num_ids), pytrace=False)
+            nodeid = self.definition.nodeid
+            fail(
+                f"In {nodeid}: {len(parametersets)} parameter sets specified, with different number of ids: {num_ids}",
+                pytrace=False,
+            )
 
         return list(itertools.islice(ids, num_ids))
 
@@ -1486,6 +1481,7 @@ def _resolve_args_directness(
         :returns
             A dict mapping each arg name to either "indirect" or "direct".
         """
+        nodeid = self.definition.nodeid
         arg_directness: dict[str, Literal["indirect", "direct"]]
         if isinstance(indirect, bool):
             arg_directness = dict.fromkeys(
@@ -1496,14 +1492,13 @@ def _resolve_args_directness(
             for arg in indirect:
                 if arg not in argnames:
                     fail(
-                        f"In {self.function.__name__}: indirect fixture '{arg}' doesn't exist",
+                        f"In {nodeid}: indirect fixture '{arg}' doesn't exist",
                         pytrace=False,
                     )
                 arg_directness[arg] = "indirect"
         else:
             fail(
-                f"In {self.function.__name__}: expected Sequence or boolean"
-                f" for indirect, got {type(indirect).__name__}",
+                f"In {nodeid}: expected Sequence or boolean for indirect, got {type(indirect).__name__}",
                 pytrace=False,
             )
         return arg_directness
@@ -1520,12 +1515,12 @@ def _validate_if_using_arg_names(
         :raises ValueError: If validation fails.
         """
         default_arg_names = set(get_default_arg_names(self.function))
-        func_name = self.function.__name__
+        nodeid = self.definition.nodeid
         for arg in argnames:
             if arg not in self.fixturenames:
                 if arg in default_arg_names:
                     fail(
-                        f"In {func_name}: function already takes an argument '{arg}' with a default value",
+                        f"In {nodeid}: function already takes an argument '{arg}' with a default value",
                         pytrace=False,
                     )
                 else:
@@ -1534,7 +1529,7 @@ def _validate_if_using_arg_names(
                     else:
                         name = "fixture" if indirect else "argument"
                     fail(
-                        f"In {func_name}: function uses no {name} '{arg}'",
+                        f"In {nodeid}: function uses no {name} '{arg}'",
                         pytrace=False,
                     )
 

testing/python/metafunc.py

@@ -119,7 +119,7 @@ def gen() -> Iterator[int | None | Exc]:
         with pytest.raises(
             fail.Exception,
             match=(
-                r"In func: ids contains unsupported value Exc\(from_gen\) \(type: <class .*Exc'>\) at index 2. "
+                r"In mock::nodeid: ids contains unsupported value Exc\(from_gen\) \(type: <class .*Exc'>\) at index 2. "
                 r"Supported types are: .*"
             ),
         ):
@@ -300,7 +300,7 @@ class A:
         deadline=400.0
     )  # very close to std deadline and CI boxes are not reliable in CPU power
     def test_idval_hypothesis(self, value) -> None:
-        escaped = IdMaker([], [], None, None, None, None, None)._idval(value, "a", 6)
+        escaped = IdMaker([], [], None, None, None, None)._idval(value, "a", 6)
         assert isinstance(escaped, str)
         escaped.encode("ascii")
 
@@ -323,8 +323,7 @@ def test_unicode_idval(self) -> None:
         ]
         for val, expected in values:
             assert (
-                IdMaker([], [], None, None, None, None, None)._idval(val, "a", 6)
-                == expected
+                IdMaker([], [], None, None, None, None)._idval(val, "a", 6) == expected
             )
 
     def test_unicode_idval_with_config(self) -> None:
@@ -353,7 +352,7 @@ def getini(self, name):
             ("ação", MockConfig({option: False}), "a\\xe7\\xe3o"),
         ]
         for val, config, expected in values:
-            actual = IdMaker([], [], None, None, config, None, None)._idval(val, "a", 6)
+            actual = IdMaker([], [], None, None, config, None)._idval(val, "a", 6)
             assert actual == expected
 
     def test_bytes_idval(self) -> None:
@@ -367,8 +366,7 @@ def test_bytes_idval(self) -> None:
         ]
         for val, expected in values:
             assert (
-                IdMaker([], [], None, None, None, None, None)._idval(val, "a", 6)
-                == expected
+                IdMaker([], [], None, None, None, None)._idval(val, "a", 6) == expected
             )
 
     def test_class_or_function_idval(self) -> None:
@@ -384,8 +382,7 @@ def test_function():
         values = [(TestClass, "TestClass"), (test_function, "test_function")]
         for val, expected in values:
             assert (
-                IdMaker([], [], None, None, None, None, None)._idval(val, "a", 6)
-                == expected
+                IdMaker([], [], None, None, None, None)._idval(val, "a", 6) == expected
             )
 
     def test_notset_idval(self) -> None:
@@ -394,9 +391,7 @@ def test_notset_idval(self) -> None:
 
         Regression test for #7686.
         """
-        assert (
-            IdMaker([], [], None, None, None, None, None)._idval(NOTSET, "a", 0) == "a0"
-        )
+        assert IdMaker([], [], None, None, None, None)._idval(NOTSET, "a", 0) == "a0"
 
     def test_idmaker_autoname(self) -> None:
         """#250"""
@@ -407,7 +402,6 @@ def test_idmaker_autoname(self) -> None:
             None,
             None,
             None,
-            None,
         ).make_unique_parameterset_ids()
         assert result == ["string-1.0", "st-ring-2.0"]
 
@@ -418,18 +412,17 @@ def test_idmaker_autoname(self) -> None:
             None,
             None,
             None,
-            None,
         ).make_unique_parameterset_ids()
         assert result == ["a0-1.0", "a1-b1"]
         # unicode mixing, issue250
         result = IdMaker(
-            ("a", "b"), [pytest.param({}, b"\xc3\xb4")], None, None, None, None, None
+            ("a", "b"), [pytest.param({}, b"\xc3\xb4")], None, None, None, None
         ).make_unique_parameterset_ids()
         assert result == ["a0-\\xc3\\xb4"]
 
     def test_idmaker_with_bytes_regex(self) -> None:
         result = IdMaker(
-            ("a"), [pytest.param(re.compile(b"foo"))], None, None, None, None, None
+            ("a"), [pytest.param(re.compile(b"foo"))], None, None, None, None
         ).make_unique_parameterset_ids()
         assert result == ["foo"]
 
@@ -455,7 +448,6 @@ def test_idmaker_native_strings(self) -> None:
             None,
             None,
             None,
-            None,
         ).make_unique_parameterset_ids()
         assert result == [
             "1.0--1.1",
@@ -488,7 +480,6 @@ def test_idmaker_non_printable_characters(self) -> None:
             None,
             None,
             None,
-            None,
         ).make_unique_parameterset_ids()
         assert result == ["\\x00-1", "\\x05-2", "\\x00-3", "\\x05-4", "\\t-5", "\\t-6"]
 
@@ -503,15 +494,14 @@ def test_idmaker_manual_ids_must_be_printable(self) -> None:
             None,
             None,
             None,
-            None,
         ).make_unique_parameterset_ids()
         assert result == ["hello \\x00", "hello \\x05"]
 
     def test_idmaker_enum(self) -> None:
         enum = pytest.importorskip("enum")
         e = enum.Enum("Foo", "one, two")
         result = IdMaker(
-            ("a", "b"), [pytest.param(e.one, e.two)], None, None, None, None, None
+            ("a", "b"), [pytest.param(e.one, e.two)], None, None, None, None
         ).make_unique_parameterset_ids()
         assert result == ["Foo.one-Foo.two"]
 
@@ -534,7 +524,6 @@ def ids(val: object) -> str | None:
             None,
             None,
             None,
-            None,
         ).make_unique_parameterset_ids()
         assert result == ["10.0-IndexError()", "20-KeyError()", "three-b2"]
 
@@ -555,7 +544,6 @@ def ids(val: object) -> str:
             None,
             None,
             None,
-            None,
         ).make_unique_parameterset_ids()
         assert result == ["a-a0", "a-a1", "a-a2"]
 
@@ -593,7 +581,6 @@ def getini(self, name):
                 None,
                 config,
                 None,
-                None,
             ).make_unique_parameterset_ids()
             assert result == [expected]
 
@@ -625,7 +612,7 @@ def getini(self, name):
         ]
         for config, expected in values:
             result = IdMaker(
-                ("a",), [pytest.param("string")], None, ["ação"], config, None, None
+                ("a",), [pytest.param("string")], None, ["ação"], config, None
             ).make_unique_parameterset_ids()
             assert result == [expected]
 
@@ -656,14 +643,13 @@ def getini(self, name):
                 None,
                 config,
                 None,
-                None,
             ).make_unique_parameterset_ids()
             assert result == [expected]
 
     def test_idmaker_duplicated_empty_str(self) -> None:
         """Regression test for empty strings parametrized more than once (#11563)."""
         result = IdMaker(
-            ("a",), [pytest.param(""), pytest.param("")], None, None, None, None, None
+            ("a",), [pytest.param(""), pytest.param("")], None, None, None, None
         ).make_unique_parameterset_ids()
         assert result == ["0", "1"]
 
@@ -728,7 +714,6 @@ def test_idmaker_with_ids(self) -> None:
             ["a", None],
             None,
             None,
-            None,
         ).make_unique_parameterset_ids()
         assert result == ["a", "3-4"]
 
@@ -740,7 +725,6 @@ def test_idmaker_with_paramset_id(self) -> None:
             ["a", None],
             None,
             None,
-            None,
         ).make_unique_parameterset_ids()
         assert result == ["me", "you"]
 
@@ -752,7 +736,6 @@ def test_idmaker_with_ids_unique_names(self) -> None:
             ["a", "a", "b", "c", "b"],
             None,
             None,
-            None,
         ).make_unique_parameterset_ids()
         assert result == ["a0", "a1", "b0", "c", "b1"]
 
@@ -811,7 +794,7 @@ def func(x, y):
         metafunc = self.Metafunc(func)
         with pytest.raises(
             fail.Exception,
-            match="In func: expected Sequence or boolean for indirect, got dict",
+            match="In mock::nodeid: expected Sequence or boolean for indirect, got dict",
         ):
             metafunc.parametrize("x, y", [("a", "b")], indirect={})  # type: ignore[arg-type]
 
@@ -1431,7 +1414,8 @@ def test_ids_numbers(x,expected):
         result = pytester.runpytest()
         result.stdout.fnmatch_lines(
             [
-                "In test_ids_numbers: ids contains unsupported value OSError() (type: <class 'OSError'>) at index 2. "
+                "In test_parametrized_ids_invalid_type.py::test_ids_numbers: ids contains unsupported value "
+                "OSError() (type: <class 'OSError'>) at index 2. "
                 "Supported types are: str, bytes, int, float, complex, bool, enum, regex or anything with a __name__."
             ]
         )
@@ -2303,8 +2287,8 @@ def test_func(foo, bar):
                 "",
                 "*= ERRORS =*",
                 "*_ ERROR collecting test_multiple_hidden_param_is_forbidden.py _*",
-                "E   Failed: In test_func: multiple instances of HIDDEN_PARAM cannot be used "
-                "in the same parametrize call, because the tests names need to be unique.",
+                "E   Failed: In test_multiple_hidden_param_is_forbidden.py::test_func: multiple instances of "
+                "HIDDEN_PARAM cannot be used in the same parametrize call, because the tests names need to be unique.",
                 "*! Interrupted: 1 error during collection !*",
                 "*= no tests collected, 1 error in *",
             ]
@@ -2318,12 +2302,16 @@ def test_multiple_hidden_param_is_forbidden_idmaker(self) -> None:
             [pytest.HIDDEN_PARAM, pytest.HIDDEN_PARAM],
             None,
             "some_node_id",
-            None,
         )
         expected = "In some_node_id: multiple instances of HIDDEN_PARAM"
         with pytest.raises(Failed, match=expected):
             id_maker.make_unique_parameterset_ids()
 
+    def test_idmaker_error_without_nodeid(self) -> None:
+        id_maker = IdMaker(["a"], [pytest.param("a")], None, [object()], None, None)
+        with pytest.raises(Failed, match="ids contains unsupported value"):
+            id_maker.make_unique_parameterset_ids()
+
     def test_multiple_parametrize(self, pytester: Pytester) -> None:
         items = pytester.getitems(
             """