Support passing name and doc to PyCFunction::new_closure. Fixes PyO3#…

…2665

newsfragments/2686.changed.md

@@ -0,0 +1 @@
+Change PyCFunction::new_closure to take name and doc arguments.

src/types/function.rs

@@ -102,11 +102,16 @@ impl PyCFunction {
     ///         let i = args.extract::<(i64,)>()?.0;
     ///         Ok(i+1)
     ///     };
-    ///     let add_one = types::PyCFunction::new_closure(add_one, py).unwrap();
+    ///     let add_one = types::PyCFunction::new_closure(py, None, None, add_one).unwrap();
     ///     py_run!(py, add_one, "assert add_one(42) == 43");
     /// });
     /// ```
-    pub fn new_closure<F, R>(f: F, py: Python<'_>) -> PyResult<&PyCFunction>
+    pub fn new_closure<'a, F, R>(
+        py: Python<'a>,
+        name: Option<&'static str>,
+        doc: Option<&'static str>,
+        f: F,
+    ) -> PyResult<&'a PyCFunction>
     where
         F: Fn(&types::PyTuple, Option<&types::PyDict>) -> R + Send + 'static,
         R: crate::callback::IntoPyCallbackOutput<*mut ffi::PyObject>,
@@ -123,9 +128,9 @@ impl PyCFunction {
             )?
         };
         let method_def = pymethods::PyMethodDef::cfunction_with_keywords(
-            "pyo3-closure",
+            name.unwrap_or("pyo3-closure\0"),
             pymethods::PyCFunctionWithKeywords(run_closure::<F, R>),
-            "",
+            doc.unwrap_or("\0"),
         );
         Self::internal_new_from_pointers(&method_def, py, capsule.as_ptr(), std::ptr::null_mut())
     }

tests/test_pyfunction.rs

@@ -418,9 +418,11 @@ fn test_closure() {
                 Ok(res)
             })
         };
-        let closure_py = PyCFunction::new_closure(f, py).unwrap();
+        let closure_py = PyCFunction::new_closure(py, Some("test_fn"), Some("test_fn doc"), f).unwrap();
 
         py_assert!(py, closure_py, "closure_py(42) == [43]");
+        py_assert!(py, closure_py, "closure_py.__name__ == 'test_fn'");
+        py_assert!(py, closure_py, "closure_py.__doc__ == 'test_fn doc'");
         py_assert!(
             py,
             closure_py,
@@ -439,7 +441,8 @@ fn test_closure_counter() {
                 *counter += 1;
                 Ok(*counter)
             };
-        let counter_py = PyCFunction::new_closure(counter_fn, py).unwrap();
+        let counter_py =
+            PyCFunction::new_closure(py, None, None, counter_fn).unwrap();
 
         py_assert!(py, counter_py, "counter_py() == 1");
         py_assert!(py, counter_py, "counter_py() == 2");

tests/ui/invalid_closure.rs

@@ -10,7 +10,7 @@ fn main() {
             println!("This is five: {:?}", ref_.len());
             Ok(())
         };
-        PyCFunction::new_closure(closure_fn, py).unwrap().into()
+        PyCFunction::new_closure(py, None, None, closure_fn).unwrap().into()
     });
 
     Python::with_gil(|py| {

tests/ui/invalid_closure.stderr

@@ -4,8 +4,8 @@ error[E0597]: `local_data` does not live long enough
 7  |         let ref_: &[u8] = &local_data;
    |                           ^^^^^^^^^^^ borrowed value does not live long enough
 ...
-13 |         PyCFunction::new_closure(closure_fn, py).unwrap().into()
-   |         ---------------------------------------- argument requires that `local_data` is borrowed for `'static`
+13 |         PyCFunction::new_closure(py, None, None, closure_fn).unwrap().into()
+   |         ---------------------------------------------------- argument requires that `local_data` is borrowed for `'static`
 14 |     });
    |     - `local_data` dropped here while still borrowed
 
@@ -20,8 +20,8 @@ error[E0373]: closure may outlive the current function, but it borrows `ref_`, w
 note: function requires argument type to outlive `'static`
   --> tests/ui/invalid_closure.rs:13:9
    |
-13 |         PyCFunction::new_closure(closure_fn, py).unwrap().into()
-   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+13 |         PyCFunction::new_closure(py, None, None, closure_fn).unwrap().into()
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 help: to force the closure to take ownership of `ref_` (and any other referenced variables), use the `move` keyword
    |
 9  |         let closure_fn = move |_args: &PyTuple, _kwargs: Option<&PyDict>| -> PyResult<()> {