DO NOT MERGE: Test with memoffset/unstable_offset_of feature

[joshlf]

Testing as part of rust-lang/rust#111839

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[joshlf]

I tested this locally. I got trybuild failures, which seem to be a result of a compiler version mismatch, although I'm not sure what compiler version was used to generated .stderr files.

Specifically, I ran:

$ TRYBUILD=overwrite cargo +nightly test --features memoffset/unstable_offset_of

Then, I ran the same command without TRYBUILD=overwrite, and tests passed.

Here's the diff, which shows that the .stderr file output seems to just be cosmetic; no actual behavior changes:

Diff

$ git diff
diff --git a/tests/ui/deprecations.stderr b/tests/ui/deprecations.stderr
index d1b2c301..fbd893e7 100644
--- a/tests/ui/deprecations.stderr
+++ b/tests/ui/deprecations.stderr
@@ -14,4 +14,4 @@ error: use of deprecated constant `pyo3::impl_::deprecations::PYCLASS_TEXT_SIGNA
  --> tests/ui/deprecations.rs:6:8
   |
 6 | #[pyo3(text_signature = "()")]
-  |        ^^^^^^^^^^^^^^
+  |        ^^^^^^^^^^^^^^^^^^^^^
diff --git a/tests/ui/invalid_frompy_derive.stderr b/tests/ui/invalid_frompy_derive.stderr
index 8ed03caa..077c3150 100644
--- a/tests/ui/invalid_frompy_derive.stderr
+++ b/tests/ui/invalid_frompy_derive.stderr
@@ -130,7 +130,7 @@ error: only one of `attribute` or `item` can be provided
    --> tests/ui/invalid_frompy_derive.rs:118:5
     |
 118 |     #[pyo3(item, attribute)]
-    |     ^
+    |     ^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: expected one of: `transparent`, `from_item_all`, `annotation`, `crate`
    --> tests/ui/invalid_frompy_derive.rs:123:8
@@ -154,13 +154,15 @@ error: FromPyObject can be derived with at most one lifetime parameter
    --> tests/ui/invalid_frompy_derive.rs:141:22
     |
 141 | enum TooManyLifetimes<'a, 'b> {
-    |                      ^
+    |                      ^^^^^^^^
 
 error: #[derive(FromPyObject)] is not supported for unions
    --> tests/ui/invalid_frompy_derive.rs:147:1
     |
-147 | union Union {
-    | ^^^^^
+147 | / union Union {
+148 | |     a: usize,
+149 | | }
+    | |_^
 
 error: cannot derive FromPyObject for empty structs and variants
    --> tests/ui/invalid_frompy_derive.rs:151:10
@@ -186,7 +188,7 @@ error: `getter` is not permitted on tuple struct elements.
    --> tests/ui/invalid_frompy_derive.rs:169:27
     |
 169 | struct InvalidTupleGetter(#[pyo3(item("foo"))] String);
-    |                           ^
+    |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: `transparent` structs may not have a `getter` for the inner field
    --> tests/ui/invalid_frompy_derive.rs:175:5
diff --git a/tests/ui/invalid_frozen_pyclass_borrow.stderr b/tests/ui/invalid_frozen_pyclass_borrow.stderr
index 5e09d512..9f166bfc 100644
--- a/tests/ui/invalid_frozen_pyclass_borrow.stderr
+++ b/tests/ui/invalid_frozen_pyclass_borrow.stderr
@@ -8,7 +8,7 @@ error[E0271]: type mismatch resolving `<Foo as PyClass>::Frozen == False`
   --> tests/ui/invalid_frozen_pyclass_borrow.rs:11:19
    |
 11 |     fn mut_method(&mut self) {}
-   |                   ^ expected `False`, found `True`
+   |                   ^^^^^^^^^ expected `False`, found `True`
    |
 note: required by a bound in `extract_pyclass_ref_mut`
   --> src/impl_/extract_argument.rs
diff --git a/tests/ui/invalid_need_module_arg_position.stderr b/tests/ui/invalid_need_module_arg_position.stderr
index 8fce151f..d5824bc3 100644
--- a/tests/ui/invalid_need_module_arg_position.stderr
+++ b/tests/ui/invalid_need_module_arg_position.stderr
@@ -2,4 +2,4 @@ error: expected &PyModule as first argument with `pass_module`
  --> tests/ui/invalid_need_module_arg_position.rs:6:21
   |
 6 |     fn fail(string: &str, module: &PyModule) -> PyResult<&str> {
-  |                     ^
+  |                     ^^^^
diff --git a/tests/ui/invalid_property_args.stderr b/tests/ui/invalid_property_args.stderr
index a41b6c79..df87335d 100644
--- a/tests/ui/invalid_property_args.stderr
+++ b/tests/ui/invalid_property_args.stderr
@@ -38,7 +38,7 @@ error: `name` may only be specified once
   --> tests/ui/invalid_property_args.rs:37:42
    |
 37 | struct MultipleName(#[pyo3(name = "foo", name = "bar")] i32);
-   |                                          ^^^^
+   |                                          ^^^^^^^^^^^^
 
 error: `name` is useless without `get` or `set`
   --> tests/ui/invalid_property_args.rs:40:33
diff --git a/tests/ui/invalid_pyclass_enum.stderr b/tests/ui/invalid_pyclass_enum.stderr
index 8f340a76..0cd775eb 100644
--- a/tests/ui/invalid_pyclass_enum.stderr
+++ b/tests/ui/invalid_pyclass_enum.stderr
@@ -8,7 +8,7 @@ error: enums can't extend from other classes
  --> tests/ui/invalid_pyclass_enum.rs:9:11
   |
 9 | #[pyclass(extends = PyList)]
-  |           ^^^^^^^
+  |           ^^^^^^^^^^^^^^^^
 
 error: #[pyclass] can't be used on enums without any variants
   --> tests/ui/invalid_pyclass_enum.rs:16:18
diff --git a/tests/ui/invalid_pyfunction_signatures.stderr b/tests/ui/invalid_pyfunction_signatures.stderr
index dbca169d..3afdedcd 100644
--- a/tests/ui/invalid_pyfunction_signatures.stderr
+++ b/tests/ui/invalid_pyfunction_signatures.stderr
@@ -26,7 +26,7 @@ error: `*args` not allowed after `*`
   --> tests/ui/invalid_pyfunction_signatures.rs:25:24
    |
 25 | #[pyo3(signature = (*, *args))]
-   |                        ^
+   |                        ^^^^^
 
 error: `*` not allowed after `*`
   --> tests/ui/invalid_pyfunction_signatures.rs:31:24
@@ -38,13 +38,13 @@ error: `*args` not allowed after `**kwargs`
   --> tests/ui/invalid_pyfunction_signatures.rs:35:31
    |
 35 | #[pyo3(signature = (**kwargs, *args))]
-   |                               ^
+   |                               ^^^^^
 
 error: `**kwargs_b` not allowed after `**kwargs_a`
   --> tests/ui/invalid_pyfunction_signatures.rs:41:33
    |
 41 | #[pyo3(signature = (**kwargs_a, **kwargs_b))]
-   |                                 ^
+   |                                 ^^^^^^^^^^
 
 error: arguments of type `Python` must not be part of the signature
   --> tests/ui/invalid_pyfunction_signatures.rs:47:27
diff --git a/tests/ui/invalid_pyfunctions.stderr b/tests/ui/invalid_pyfunctions.stderr
index 9f140926..5514b36a 100644
--- a/tests/ui/invalid_pyfunctions.stderr
+++ b/tests/ui/invalid_pyfunctions.stderr
@@ -8,7 +8,7 @@ error: Python functions cannot have `impl Trait` arguments
  --> tests/ui/invalid_pyfunctions.rs:7:36
   |
 7 | fn impl_trait_function(impl_trait: impl AsRef<PyAny>) {}
-  |                                    ^^^^
+  |                                    ^^^^^^^^^^^^^^^^^
 
 error: `async fn` is not yet supported for Python functions.
 
diff --git a/tests/ui/invalid_pymethod_names.stderr b/tests/ui/invalid_pymethod_names.stderr
index 1e7a6f44..7ded46d1 100644
--- a/tests/ui/invalid_pymethod_names.stderr
+++ b/tests/ui/invalid_pymethod_names.stderr
@@ -8,7 +8,7 @@ error: `name` may only be specified once
   --> tests/ui/invalid_pymethod_names.rs:18:12
    |
 18 |     #[pyo3(name = "bar")]
-   |            ^^^^
+   |            ^^^^^^^^^^^^
 
 error: `name` not allowed with `#[new]`
   --> tests/ui/invalid_pymethod_names.rs:24:19
diff --git a/tests/ui/invalid_pymethods.stderr b/tests/ui/invalid_pymethods.stderr
index 24fb5242..7cfda7f7 100644
--- a/tests/ui/invalid_pymethods.stderr
+++ b/tests/ui/invalid_pymethods.stderr
@@ -8,43 +8,43 @@ error: `#[classattr]` does not take any arguments
   --> tests/ui/invalid_pymethods.rs:14:5
    |
 14 |     #[classattr(foobar)]
-   |     ^
+   |     ^^^^^^^^^^^^^^^^^^^^
 
 error: static method needs #[staticmethod] attribute
   --> tests/ui/invalid_pymethods.rs:20:5
    |
 20 |     fn staticmethod_without_attribute() {}
-   |     ^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: unexpected receiver
   --> tests/ui/invalid_pymethods.rs:26:35
    |
 26 |     fn staticmethod_with_receiver(&self) {}
-   |                                   ^
+   |                                   ^^^^^
 
 error: Expected `cls: &PyType` as the first argument to `#[classmethod]`
   --> tests/ui/invalid_pymethods.rs:32:34
    |
 32 |     fn classmethod_with_receiver(&self) {}
-   |                                  ^
+   |                                  ^^^^^
 
 error: expected receiver for `#[getter]`
   --> tests/ui/invalid_pymethods.rs:38:5
    |
 38 |     fn getter_without_receiver() {}
-   |     ^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: expected receiver for `#[setter]`
   --> tests/ui/invalid_pymethods.rs:44:5
    |
 44 |     fn setter_without_receiver() {}
-   |     ^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: static method needs #[staticmethod] attribute
   --> tests/ui/invalid_pymethods.rs:50:5
    |
 50 |     fn text_signature_on_call() {}
-   |     ^^
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: `text_signature` not allowed with `getter`
   --> tests/ui/invalid_pymethods.rs:56:12
@@ -74,7 +74,7 @@ error: `text_signature` may only be specified once
   --> tests/ui/invalid_pymethods.rs:83:12
    |
 83 |     #[pyo3(text_signature = None)]
-   |            ^^^^^^^^^^^^^^
+   |            ^^^^^^^^^^^^^^^^^^^^^
 
 error: `signature` not allowed with `getter`
   --> tests/ui/invalid_pymethods.rs:90:12
@@ -97,15 +97,21 @@ error: `signature` not allowed with `classattr`
 error: `#[new]` may not be combined with `#[classmethod]` `#[staticmethod]`, `#[classattr]`, `#[getter]`, and `#[setter]`
    --> tests/ui/invalid_pymethods.rs:110:7
     |
-110 |     #[new]
-    |       ^^^
+110 |       #[new]
+    |  _______^
+111 | |     #[classmethod]
+112 | |     #[staticmethod]
+113 | |     #[classattr]
+114 | |     #[getter(x)]
+115 | |     #[setter(x)]
+    | |____________^
 
 error: `#[new]` does not take any arguments
        = help: did you mean `#[new] #[pyo3(signature = ())]`?
    --> tests/ui/invalid_pymethods.rs:121:7
     |
 121 |     #[new(signature = ())]
-    |       ^^^
+    |       ^^^^^^^^^^^^^^^^^^^
 
 error: `#[new]` does not take any arguments
        = note: this was previously accepted and ignored
@@ -119,21 +125,21 @@ error: `#[classmethod]` does not take any arguments
    --> tests/ui/invalid_pymethods.rs:133:7
     |
 133 |     #[classmethod(signature = ())]
-    |       ^^^^^^^^^^^
+    |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: `#[staticmethod]` does not take any arguments
        = help: did you mean `#[staticmethod] #[pyo3(signature = ())]`?
    --> tests/ui/invalid_pymethods.rs:139:7
     |
 139 |     #[staticmethod(signature = ())]
-    |       ^^^^^^^^^^^^
+    |       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: `#[classattr]` does not take any arguments
        = help: did you mean `#[classattr] #[pyo3(signature = ())]`?
    --> tests/ui/invalid_pymethods.rs:145:7
     |
 145 |     #[classattr(signature = ())]
-    |       ^^^^^^^^^
+    |       ^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: Python functions cannot have generic type parameters
    --> tests/ui/invalid_pymethods.rs:151:23
@@ -145,13 +151,13 @@ error: Python functions cannot have `impl Trait` arguments
    --> tests/ui/invalid_pymethods.rs:156:48
     |
 156 |     fn impl_trait_method_first_arg(impl_trait: impl AsRef<PyAny>) {}
-    |                                                ^^^^
+    |                                                ^^^^^^^^^^^^^^^^^
 
 error: Python functions cannot have `impl Trait` arguments
    --> tests/ui/invalid_pymethods.rs:161:56
     |
 161 |     fn impl_trait_method_second_arg(&self, impl_trait: impl AsRef<PyAny>) {}
-    |                                                        ^^^^
+    |                                                        ^^^^^^^^^^^^^^^^^
 
 error: `async fn` is not yet supported for Python functions.
 
@@ -179,7 +185,7 @@ error: macros cannot be used as items in `#[pymethods]` impl blocks
    --> tests/ui/invalid_pymethods.rs:212:5
     |
 212 |     macro_invocation!();
-    |     ^^^^^^^^^^^^^^^^
+    |     ^^^^^^^^^^^^^^^^^^^^
 
 error[E0119]: conflicting implementations of trait `pyo3::impl_::pyclass::PyClassNewTextSignature<TwoNew>` for type `pyo3::impl_::pyclass::PyClassImplCollector<TwoNew>`
    --> tests/ui/invalid_pymethods.rs:182:1
diff --git a/tests/ui/reject_generics.stderr b/tests/ui/reject_generics.stderr
index 2285b927..a4250e74 100644
--- a/tests/ui/reject_generics.stderr
+++ b/tests/ui/reject_generics.stderr
@@ -2,7 +2,7 @@ error: #[pyclass] cannot have generic parameters. For an explanation, see https:
  --> tests/ui/reject_generics.rs:4:25
   |
 4 | struct ClassWithGenerics<A> {
-  |                         ^
+  |                         ^^^
 
 error: #[pyclass] cannot have lifetime parameters. For an explanation, see https://pyo3.rs/latest/class.html#no-lifetime-parameters
  --> tests/ui/reject_generics.rs:9:27

</details>

[adamreichold]

I tested this locally. I got trybuild failures, which seem to be a result of a compiler version mismatch, although I'm not sure what compiler version was used to generated .stderr files.

As indicated by

pyo3/.github/workflows/build.yml

Lines 60 to 62 in 8c8f00e

	- if: inputs.rust != 'stable'
	name: Ignore changed error messages when using trybuild
	run: echo "TRYBUILD=overwrite" >> "$GITHUB_ENV"

we check the compiler output only on the current stable.

[davidhewitt]

Also @joshlf if you want this more permanently tested in our CI, I think it'd be fine to update our nightly feature to depend on the memoffset/unstable_offset_of feature.

[joshlf]

Also @joshlf if you want this more permanently tested in our CI, I think it'd be fine to update our nightly feature to depend on the memoffset/unstable_offset_of feature.

We've got what we need for rust-lang/rust#111839, but thanks!