Fix some clippy lints

pyo3-derive-backend/src/pyproto.rs

@@ -47,10 +47,10 @@ pub fn build_py_proto(ast: &mut syn::ItemImpl) -> syn::Result<TokenStream> {
 
         Ok(tokens)
     } else {
-        return Err(syn::Error::new_spanned(
+        Err(syn::Error::new_spanned(
             ast,
             "#[pyproto] can only be used with protocol trait implementations",
-        ));
+        ))
     }
 }
 

src/class/basic.rs

@@ -221,7 +221,7 @@ where
             // Behave like python's __getattr__ (as opposed to __getattribute__) and check
             // for existing fields and methods first
             let existing = ffi::PyObject_GenericGetAttr(slf, arg);
-            if existing == std::ptr::null_mut() {
+            if existing.is_null() {
                 // PyObject_HasAttr also tries to get an object and clears the error if it fails
                 ffi::PyErr_Clear();
             } else {
@@ -233,7 +233,7 @@ where
 
             let result = match arg.extract() {
                 Ok(arg) => slf.__getattr__(arg).into(),
-                Err(e) => Err(e.into()),
+                Err(e) => Err(e),
             };
             crate::callback::cb_convert(PyObjectCallbackConverter, py, result)
         }

src/types/tuple.rs

@@ -21,10 +21,7 @@ pyobject_native_type!(PyTuple, ffi::PyTuple_Type, ffi::PyTuple_Check);
 
 impl PyTuple {
     /// Construct a new tuple with the given elements.
-    pub fn new<'p, T, U>(
-        py: Python<'p>,
-        elements: impl IntoIterator<Item = T, IntoIter = U>,
-    ) -> &'p PyTuple
+    pub fn new<T, U>(py: Python, elements: impl IntoIterator<Item = T, IntoIter = U>) -> &PyTuple
     where
         T: ToPyObject,
         U: ExactSizeIterator<Item = T>,
@@ -41,7 +38,7 @@ impl PyTuple {
     }
 
     /// Retrieves the empty tuple.
-    pub fn empty<'p>(py: Python<'p>) -> &'p PyTuple {
+    pub fn empty(py: Python) -> &PyTuple {
         unsafe { py.from_owned_ptr(ffi::PyTuple_New(0)) }
     }