use std::fmt::Display;
use proc_macro2::{Span, TokenStream};
use quote::{format_ident, quote, quote_spanned, ToTokens};
use syn::{ext::IdentExt, spanned::Spanned, Ident, Result};
use crate::utils::Ctx;
use crate::{
attributes::{TextSignatureAttribute, TextSignatureAttributeValue},
deprecations::{Deprecation, Deprecations},
params::{impl_arg_params, Holders},
pyfunction::{
FunctionSignature, PyFunctionArgPyO3Attributes, PyFunctionOptions, SignatureAttribute,
},
quotes,
utils::{self, is_abi3, PythonDoc},
};
#[derive(Clone, Debug)]
pub struct FnArg<'a> {
pub name: &'a syn::Ident,
pub ty: &'a syn::Type,
pub optional: Option<&'a syn::Type>,
pub default: Option<syn::Expr>,
pub py: bool,
pub attrs: PyFunctionArgPyO3Attributes,
pub is_varargs: bool,
pub is_kwargs: bool,
pub is_cancel_handle: bool,
}
impl<'a> FnArg<'a> {
pub fn parse(arg: &'a mut syn::FnArg) -> Result<Self> {
match arg {
syn::FnArg::Receiver(recv) => {
bail_spanned!(recv.span() => "unexpected receiver")
} syn::FnArg::Typed(cap) => {
if let syn::Type::ImplTrait(_) = &*cap.ty {
bail_spanned!(cap.ty.span() => IMPL_TRAIT_ERR);
}
let arg_attrs = PyFunctionArgPyO3Attributes::from_attrs(&mut cap.attrs)?;
let ident = match &*cap.pat {
syn::Pat::Ident(syn::PatIdent { ident, .. }) => ident,
other => return Err(handle_argument_error(other)),
};
let is_cancel_handle = arg_attrs.cancel_handle.is_some();
Ok(FnArg {
name: ident,
ty: &cap.ty,
optional: utils::option_type_argument(&cap.ty),
default: None,
py: utils::is_python(&cap.ty),
attrs: arg_attrs,
is_varargs: false,
is_kwargs: false,
is_cancel_handle,
})
}
}
}
pub fn is_regular(&self) -> bool {
!self.py && !self.is_cancel_handle && !self.is_kwargs && !self.is_varargs
}
}
fn handle_argument_error(pat: &syn::Pat) -> syn::Error {
let span = pat.span();
let msg = match pat {
syn::Pat::Wild(_) => "wildcard argument names are not supported",
syn::Pat::Struct(_)
| syn::Pat::Tuple(_)
| syn::Pat::TupleStruct(_)
| syn::Pat::Slice(_) => "destructuring in arguments is not supported",
_ => "unsupported argument",
};
syn::Error::new(span, msg)
}
#[derive(Clone, Debug)]
pub enum FnType {
Getter(SelfType),
Setter(SelfType),
Fn(SelfType),
FnNew,
FnNewClass(Span),
FnClass(Span),
FnStatic,
FnModule(Span),
ClassAttribute,
}
impl FnType {
pub fn skip_first_rust_argument_in_python_signature(&self) -> bool {
match self {
FnType::Getter(_)
| FnType::Setter(_)
| FnType::Fn(_)
| FnType::FnClass(_)
| FnType::FnNewClass(_)
| FnType::FnModule(_) => true,
FnType::FnNew | FnType::FnStatic | FnType::ClassAttribute => false,
}
}
pub fn self_arg(
&self,
cls: Option<&syn::Type>,
error_mode: ExtractErrorMode,
holders: &mut Holders,
ctx: &Ctx,
) -> TokenStream {
let Ctx { pyo3_path } = ctx;
match self {
FnType::Getter(st) | FnType::Setter(st) | FnType::Fn(st) => {
let mut receiver = st.receiver(
cls.expect("no class given for Fn with a \"self\" receiver"),
error_mode,
holders,
ctx,
);
syn::Token).to_tokens(&mut receiver);
receiver
}
FnType::FnNew | FnType::FnStatic | FnType::ClassAttribute => {
quote!()
}
FnType::FnClass(span) | FnType::FnNewClass(span) => {
let py = syn::Ident::new("py", Span::call_site());
let slf: Ident = syn::Ident::new("_slf_ref", Span::call_site());
let pyo3_path = pyo3_path.to_tokens_spanned(*span);
quote_spanned! { *span =>
#[allow(clippy::useless_conversion)]
::std::convert::Into::into(
#pyo3_path::impl_::pymethods::BoundRef::ref_from_ptr(#py, &*(#slf as *const _ as *const *mut _))
.downcast_unchecked::<#pyo3_path::types::PyType>()
),
}
}
FnType::FnModule(span) => {
let py = syn::Ident::new("py", Span::call_site());
let slf: Ident = syn::Ident::new("_slf_ref", Span::call_site());
let pyo3_path = pyo3_path.to_tokens_spanned(*span);
quote_spanned! { *span =>
#[allow(clippy::useless_conversion)]
::std::convert::Into::into(
#pyo3_path::impl_::pymethods::BoundRef::ref_from_ptr(#py, &*(#slf as *const _ as *const *mut _))
.downcast_unchecked::<#pyo3_path::types::PyModule>()
),
}
}
}
}
}
#[derive(Clone, Debug)]
pub enum SelfType {
Receiver { mutable: bool, span: Span },
TryFromBoundRef(Span),
}
#[derive(Clone, Copy)]
pub enum ExtractErrorMode {
NotImplemented,
Raise,
}
impl ExtractErrorMode {
pub fn handle_error(self, extract: TokenStream, ctx: &Ctx) -> TokenStream {
let Ctx { pyo3_path } = ctx;
match self {
ExtractErrorMode::Raise => quote! { #extract? },
ExtractErrorMode::NotImplemented => quote! {
match #extract {
::std::result::Result::Ok(value) => value,
::std::result::Result::Err(_) => { return #pyo3_path::callback::convert(py, py.NotImplemented()); },
}
},
}
}
}
impl SelfType {
pub fn receiver(
&self,
cls: &syn::Type,
error_mode: ExtractErrorMode,
holders: &mut Holders,
ctx: &Ctx,
) -> TokenStream {
let py = syn::Ident::new("py", Span::call_site());
let slf = syn::Ident::new("_slf", Span::call_site());
let Ctx { pyo3_path } = ctx;
match self {
SelfType::Receiver { span, mutable } => {
let method = if *mutable {
syn::Ident::new("extract_pyclass_ref_mut", *span)
} else {
syn::Ident::new("extract_pyclass_ref", *span)
};
let holder = holders.push_holder(*span);
let pyo3_path = pyo3_path.to_tokens_spanned(*span);
error_mode.handle_error(
quote_spanned! { *span =>
#pyo3_path::impl_::extract_argument::#method::<#cls>(
#pyo3_path::impl_::pymethods::BoundRef::ref_from_ptr(#py, &#slf).0,
&mut #holder,
)
},
ctx,
)
}
SelfType::TryFromBoundRef(span) => {
let pyo3_path = pyo3_path.to_tokens_spanned(*span);
error_mode.handle_error(
quote_spanned! { *span =>
#pyo3_path::impl_::pymethods::BoundRef::ref_from_ptr(#py, &#slf).downcast::<#cls>()
.map_err(::std::convert::Into::<#pyo3_path::PyErr>::into)
.and_then(
#[allow(unknown_lints, clippy::unnecessary_fallible_conversions)] |bound| ::std::convert::TryFrom::try_from(bound).map_err(::std::convert::Into::into)
)
},
ctx
)
}
}
}
}
#[derive(Clone, Debug)]
pub enum CallingConvention {
Noargs, Varargs, Fastcall, TpNew, }
impl CallingConvention {
pub fn from_signature(signature: &FunctionSignature<'_>) -> Self {
if signature.python_signature.has_no_args() {
Self::Noargs
} else if signature.python_signature.kwargs.is_some() {
Self::Varargs
} else if !is_abi3() {
Self::Fastcall
} else {
Self::Varargs
}
}
}
pub struct FnSpec<'a> {
pub tp: FnType,
pub name: &'a syn::Ident,
pub python_name: syn::Ident,
pub signature: FunctionSignature<'a>,
pub convention: CallingConvention,
pub text_signature: Option<TextSignatureAttribute>,
pub asyncness: Option<syn::Token![async]>,
pub unsafety: Option<syn::Token![unsafe]>,
pub deprecations: Deprecations<'a>,
}
pub fn parse_method_receiver(arg: &syn::FnArg) -> Result<SelfType> {
match arg {
syn::FnArg::Receiver(
recv @ syn::Receiver {
reference: None, ..
},
) => {
bail_spanned!(recv.span() => RECEIVER_BY_VALUE_ERR);
}
syn::FnArg::Receiver(recv @ syn::Receiver { mutability, .. }) => Ok(SelfType::Receiver {
mutable: mutability.is_some(),
span: recv.span(),
}),
syn::FnArg::Typed(syn::PatType { ty, .. }) => {
if let syn::Type::ImplTrait(_) = &**ty {
bail_spanned!(ty.span() => IMPL_TRAIT_ERR);
}
Ok(SelfType::TryFromBoundRef(ty.span()))
}
}
}
impl<'a> FnSpec<'a> {
pub fn parse(
sig: &'a mut syn::Signature,
meth_attrs: &mut Vec<syn::Attribute>,
options: PyFunctionOptions,
ctx: &'a Ctx,
) -> Result<FnSpec<'a>> {
let PyFunctionOptions {
text_signature,
name,
signature,
..
} = options;
let mut python_name = name.map(|name| name.value.0);
let mut deprecations = Deprecations::new(ctx);
let fn_type = Self::parse_fn_type(sig, meth_attrs, &mut python_name, &mut deprecations)?;
ensure_signatures_on_valid_method(&fn_type, signature.as_ref(), text_signature.as_ref())?;
let name = &sig.ident;
let python_name = python_name.as_ref().unwrap_or(name).unraw();
let arguments: Vec<_> = sig
.inputs
.iter_mut()
.skip(if fn_type.skip_first_rust_argument_in_python_signature() {
1
} else {
0
})
.map(FnArg::parse)
.collect::<Result<_>>()?;
let signature = if let Some(signature) = signature {
FunctionSignature::from_arguments_and_attribute(arguments, signature)?
} else {
FunctionSignature::from_arguments(arguments)?
};
let convention = if matches!(fn_type, FnType::FnNew | FnType::FnNewClass(_)) {
CallingConvention::TpNew
} else {
CallingConvention::from_signature(&signature)
};
Ok(FnSpec {
tp: fn_type,
name,
convention,
python_name,
signature,
text_signature,
asyncness: sig.asyncness,
unsafety: sig.unsafety,
deprecations,
})
}
pub fn null_terminated_python_name(&self) -> syn::LitStr {
syn::LitStr::new(&format!("{}\0", self.python_name), self.python_name.span())
}
fn parse_fn_type(
sig: &syn::Signature,
meth_attrs: &mut Vec<syn::Attribute>,
python_name: &mut Option<syn::Ident>,
deprecations: &mut Deprecations<'_>,
) -> Result<FnType> {
let mut method_attributes = parse_method_attributes(meth_attrs, deprecations)?;
let name = &sig.ident;
let parse_receiver = |msg: &'static str| {
let first_arg = sig
.inputs
.first()
.ok_or_else(|| err_spanned!(sig.span() => msg))?;
parse_method_receiver(first_arg)
};
let strip_fn_name = |prefix: &'static str| {
name.unraw()
.to_string()
.strip_prefix(prefix)
.map(|stripped| syn::Ident::new(stripped, name.span()))
};
let mut set_name_to_new = || {
if let Some(name) = &python_name {
bail_spanned!(name.span() => "`name` not allowed with `#[new]`");
}
*python_name = Some(syn::Ident::new("__new__", Span::call_site()));
Ok(())
};
let fn_type = match method_attributes.as_mut_slice() {
[] => FnType::Fn(parse_receiver(
"static method needs #[staticmethod] attribute",
)?),
[MethodTypeAttribute::StaticMethod(_)] => FnType::FnStatic,
[MethodTypeAttribute::ClassAttribute(_)] => FnType::ClassAttribute,
[MethodTypeAttribute::New(_)] => {
set_name_to_new()?;
FnType::FnNew
}
[MethodTypeAttribute::New(_), MethodTypeAttribute::ClassMethod(span)]
| [MethodTypeAttribute::ClassMethod(span), MethodTypeAttribute::New(_)] => {
set_name_to_new()?;
FnType::FnNewClass(*span)
}
[MethodTypeAttribute::ClassMethod(_)] => {
let span = match sig.inputs.first() {
Some(syn::FnArg::Typed(first_arg)) => first_arg.ty.span(),
Some(syn::FnArg::Receiver(_)) | None => bail_spanned!(
sig.paren_token.span.join() => "Expected `&Bound<PyType>` or `Py<PyType>` as the first argument to `#[classmethod]`"
),
};
FnType::FnClass(span)
}
[MethodTypeAttribute::Getter(_, name)] => {
if let Some(name) = name.take() {
ensure_spanned!(
python_name.replace(name).is_none(),
python_name.span() => "`name` may only be specified once"
);
} else if python_name.is_none() {
*python_name = strip_fn_name("get_");
}
FnType::Getter(parse_receiver("expected receiver for `#[getter]`")?)
}
[MethodTypeAttribute::Setter(_, name)] => {
if let Some(name) = name.take() {
ensure_spanned!(
python_name.replace(name).is_none(),
python_name.span() => "`name` may only be specified once"
);
} else if python_name.is_none() {
*python_name = strip_fn_name("set_");
}
FnType::Setter(parse_receiver("expected receiver for `#[setter]`")?)
}
[first, rest @ .., last] => {
let span = rest
.iter()
.fold(first.span(), |s, next| s.join(next.span()).unwrap_or(s));
let span = span.join(last.span()).unwrap_or(span);
let mut msg = format!("`{}` may not be combined with", first);
let mut is_first = true;
for attr in &*rest {
msg.push_str(&format!(" `{}`", attr));
if is_first {
is_first = false;
} else {
msg.push(',');
}
}
if !rest.is_empty() {
msg.push_str(" and");
}
msg.push_str(&format!(" `{}`", last));
bail_spanned!(span => msg)
}
};
Ok(fn_type)
}
pub fn get_wrapper_function(
&self,
ident: &proc_macro2::Ident,
cls: Option<&syn::Type>,
ctx: &Ctx,
) -> Result<TokenStream> {
let Ctx { pyo3_path } = ctx;
let mut cancel_handle_iter = self
.signature
.arguments
.iter()
.filter(|arg| arg.is_cancel_handle);
let cancel_handle = cancel_handle_iter.next();
if let Some(arg) = cancel_handle {
ensure_spanned!(self.asyncness.is_some(), arg.name.span() => "`cancel_handle` attribute can only be used with `async fn`");
if let Some(arg2) = cancel_handle_iter.next() {
bail_spanned!(arg2.name.span() => "`cancel_handle` may only be specified once");
}
}
if self.asyncness.is_some() {
ensure_spanned!(
cfg!(feature = "experimental-async"),
self.asyncness.span() => "async functions are only supported with the `experimental-async` feature"
);
}
let rust_call = |args: Vec<TokenStream>, holders: &mut Holders| {
let mut self_arg = || self.tp.self_arg(cls, ExtractErrorMode::Raise, holders, ctx);
let call = if self.asyncness.is_some() {
let throw_callback = if cancel_handle.is_some() {
quote! { Some(__throw_callback) }
} else {
quote! { None }
};
let python_name = &self.python_name;
let qualname_prefix = match cls {
Some(cls) => quote!(Some(<#cls as #pyo3_path::PyTypeInfo>::NAME)),
None => quote!(None),
};
let arg_names = (0..args.len())
.map(|i| format_ident!("arg_{}", i))
.collect::<Vec<_>>();
let future = match self.tp {
FnType::Fn(SelfType::Receiver { mutable: false, .. }) => {
quote! {{
#(let #arg_names = #args;)*
let __guard = #pyo3_path::impl_::coroutine::RefGuard::<#cls>::new(&#pyo3_path::impl_::pymethods::BoundRef::ref_from_ptr(py, &_slf))?;
async move { function(&__guard, #(#arg_names),*).await }
}}
}
FnType::Fn(SelfType::Receiver { mutable: true, .. }) => {
quote! {{
#(let #arg_names = #args;)*
let mut __guard = #pyo3_path::impl_::coroutine::RefMutGuard::<#cls>::new(&#pyo3_path::impl_::pymethods::BoundRef::ref_from_ptr(py, &_slf))?;
async move { function(&mut __guard, #(#arg_names),*).await }
}}
}
_ => {
let self_arg = self_arg();
if self_arg.is_empty() {
quote! { function(#(#args),*) }
} else {
let self_checker = holders.push_gil_refs_checker(self_arg.span());
quote! {
function(
#pyo3_path::impl_::deprecations::inspect_type(#self_arg &#self_checker),
#(#args),*
)
}
}
}
};
let mut call = quote! {{
let future = #future;
#pyo3_path::impl_::coroutine::new_coroutine(
#pyo3_path::intern!(py, stringify!(#python_name)),
#qualname_prefix,
#throw_callback,
async move { #pyo3_path::impl_::wrap::OkWrap::wrap(future.await) },
)
}};
if cancel_handle.is_some() {
call = quote! {{
let __cancel_handle = #pyo3_path::coroutine::CancelHandle::new();
let __throw_callback = __cancel_handle.throw_callback();
#call
}};
}
call
} else {
let self_arg = self_arg();
if self_arg.is_empty() {
quote! { function(#(#args),*) }
} else {
let self_checker = holders.push_gil_refs_checker(self_arg.span());
quote! {
function(
#pyo3_path::impl_::deprecations::inspect_type(#self_arg &#self_checker),
#(#args),*
)
}
}
};
quotes::map_result_into_ptr(quotes::ok_wrap(call, ctx), ctx)
};
let func_name = &self.name;
let rust_name = if let Some(cls) = cls {
quote!(#cls::#func_name)
} else {
quote!(#func_name)
};
Ok(match self.convention {
CallingConvention::Noargs => {
let mut holders = Holders::new();
let args = self
.signature
.arguments
.iter()
.map(|arg| {
if arg.py {
quote!(py)
} else if arg.is_cancel_handle {
quote!(__cancel_handle)
} else {
unreachable!()
}
})
.collect();
let call = rust_call(args, &mut holders);
let check_gil_refs = holders.check_gil_refs();
let init_holders = holders.init_holders(ctx);
quote! {
unsafe fn #ident<'py>(
py: #pyo3_path::Python<'py>,
_slf: *mut #pyo3_path::ffi::PyObject,
) -> #pyo3_path::PyResult<*mut #pyo3_path::ffi::PyObject> {
let _slf_ref = &_slf;
let function = #rust_name; #init_holders
let result = #call;
#check_gil_refs
result
}
}
}
CallingConvention::Fastcall => {
let mut holders = Holders::new();
let (arg_convert, args) = impl_arg_params(self, cls, true, &mut holders, ctx)?;
let call = rust_call(args, &mut holders);
let init_holders = holders.init_holders(ctx);
let check_gil_refs = holders.check_gil_refs();
quote! {
unsafe fn #ident<'py>(
py: #pyo3_path::Python<'py>,
_slf: *mut #pyo3_path::ffi::PyObject,
_args: *const *mut #pyo3_path::ffi::PyObject,
_nargs: #pyo3_path::ffi::Py_ssize_t,
_kwnames: *mut #pyo3_path::ffi::PyObject
) -> #pyo3_path::PyResult<*mut #pyo3_path::ffi::PyObject> {
let _slf_ref = &_slf;
let function = #rust_name; #arg_convert
#init_holders
let result = #call;
#check_gil_refs
result
}
}
}
CallingConvention::Varargs => {
let mut holders = Holders::new();
let (arg_convert, args) = impl_arg_params(self, cls, false, &mut holders, ctx)?;
let call = rust_call(args, &mut holders);
let init_holders = holders.init_holders(ctx);
let check_gil_refs = holders.check_gil_refs();
quote! {
unsafe fn #ident<'py>(
py: #pyo3_path::Python<'py>,
_slf: *mut #pyo3_path::ffi::PyObject,
_args: *mut #pyo3_path::ffi::PyObject,
_kwargs: *mut #pyo3_path::ffi::PyObject
) -> #pyo3_path::PyResult<*mut #pyo3_path::ffi::PyObject> {
let _slf_ref = &_slf;
let function = #rust_name; #arg_convert
#init_holders
let result = #call;
#check_gil_refs
result
}
}
}
CallingConvention::TpNew => {
let mut holders = Holders::new();
let (arg_convert, args) = impl_arg_params(self, cls, false, &mut holders, ctx)?;
let self_arg = self
.tp
.self_arg(cls, ExtractErrorMode::Raise, &mut holders, ctx);
let call = quote! { #rust_name(#self_arg #(#args),*) };
let init_holders = holders.init_holders(ctx);
let check_gil_refs = holders.check_gil_refs();
quote! {
unsafe fn #ident(
py: #pyo3_path::Python<'_>,
_slf: *mut #pyo3_path::ffi::PyTypeObject,
_args: *mut #pyo3_path::ffi::PyObject,
_kwargs: *mut #pyo3_path::ffi::PyObject
) -> #pyo3_path::PyResult<*mut #pyo3_path::ffi::PyObject> {
use #pyo3_path::callback::IntoPyCallbackOutput;
let _slf_ref = &_slf;
let function = #rust_name; #arg_convert
#init_holders
let result = #call;
let initializer: #pyo3_path::PyClassInitializer::<#cls> = result.convert(py)?;
#check_gil_refs
#pyo3_path::impl_::pymethods::tp_new_impl(py, initializer, _slf)
}
}
}
})
}
pub fn get_methoddef(&self, wrapper: impl ToTokens, doc: &PythonDoc, ctx: &Ctx) -> TokenStream {
let Ctx { pyo3_path } = ctx;
let python_name = self.null_terminated_python_name();
match self.convention {
CallingConvention::Noargs => quote! {
#pyo3_path::impl_::pymethods::PyMethodDef::noargs(
#python_name,
#pyo3_path::impl_::pymethods::PyCFunction({
unsafe extern "C" fn trampoline(
_slf: *mut #pyo3_path::ffi::PyObject,
_args: *mut #pyo3_path::ffi::PyObject,
) -> *mut #pyo3_path::ffi::PyObject
{
#pyo3_path::impl_::trampoline::noargs(
_slf,
_args,
#wrapper
)
}
trampoline
}),
#doc,
)
},
CallingConvention::Fastcall => quote! {
#pyo3_path::impl_::pymethods::PyMethodDef::fastcall_cfunction_with_keywords(
#python_name,
#pyo3_path::impl_::pymethods::PyCFunctionFastWithKeywords({
unsafe extern "C" fn trampoline(
_slf: *mut #pyo3_path::ffi::PyObject,
_args: *const *mut #pyo3_path::ffi::PyObject,
_nargs: #pyo3_path::ffi::Py_ssize_t,
_kwnames: *mut #pyo3_path::ffi::PyObject
) -> *mut #pyo3_path::ffi::PyObject
{
#pyo3_path::impl_::trampoline::fastcall_with_keywords(
_slf,
_args,
_nargs,
_kwnames,
#wrapper
)
}
trampoline
}),
#doc,
)
},
CallingConvention::Varargs => quote! {
#pyo3_path::impl_::pymethods::PyMethodDef::cfunction_with_keywords(
#python_name,
#pyo3_path::impl_::pymethods::PyCFunctionWithKeywords({
unsafe extern "C" fn trampoline(
_slf: *mut #pyo3_path::ffi::PyObject,
_args: *mut #pyo3_path::ffi::PyObject,
_kwargs: *mut #pyo3_path::ffi::PyObject,
) -> *mut #pyo3_path::ffi::PyObject
{
#pyo3_path::impl_::trampoline::cfunction_with_keywords(
_slf,
_args,
_kwargs,
#wrapper
)
}
trampoline
}),
#doc,
)
},
CallingConvention::TpNew => unreachable!("tp_new cannot get a methoddef"),
}
}
pub fn get_doc(&self, attrs: &[syn::Attribute]) -> PythonDoc {
let text_signature = self
.text_signature_call_signature()
.map(|sig| format!("{}{}", self.python_name, sig));
utils::get_doc(attrs, text_signature)
}
pub fn text_signature_call_signature(&self) -> Option<String> {
let self_argument = match &self.tp {
FnType::Getter(_) | FnType::Setter(_) | FnType::ClassAttribute => return None,
FnType::Fn(_) => Some("self"),
FnType::FnModule(_) => Some("module"),
FnType::FnClass(_) | FnType::FnNewClass(_) => Some("cls"),
FnType::FnStatic | FnType::FnNew => None,
};
match self.text_signature.as_ref().map(|attr| &attr.value) {
Some(TextSignatureAttributeValue::Str(s)) => Some(s.value()),
None => Some(self.signature.text_signature(self_argument)),
Some(TextSignatureAttributeValue::Disabled(_)) => None,
}
}
}
enum MethodTypeAttribute {
New(Span),
ClassMethod(Span),
StaticMethod(Span),
Getter(Span, Option<Ident>),
Setter(Span, Option<Ident>),
ClassAttribute(Span),
}
impl MethodTypeAttribute {
fn span(&self) -> Span {
match self {
MethodTypeAttribute::New(span)
| MethodTypeAttribute::ClassMethod(span)
| MethodTypeAttribute::StaticMethod(span)
| MethodTypeAttribute::Getter(span, _)
| MethodTypeAttribute::Setter(span, _)
| MethodTypeAttribute::ClassAttribute(span) => *span,
}
}
fn parse_if_matching_attribute(
attr: &syn::Attribute,
deprecations: &mut Deprecations<'_>,
) -> Result<Option<Self>> {
fn ensure_no_arguments(meta: &syn::Meta, ident: &str) -> syn::Result<()> {
match meta {
syn::Meta::Path(_) => Ok(()),
syn::Meta::List(l) => bail_spanned!(
l.span() => format!(
"`#[{ident}]` does not take any arguments\n= help: did you mean `#[{ident}] #[pyo3({meta})]`?",
ident = ident,
meta = l.tokens,
)
),
syn::Meta::NameValue(nv) => {
bail_spanned!(nv.eq_token.span() => format!(
"`#[{}]` does not take any arguments\n= note: this was previously accepted and ignored",
ident
))
}
}
}
fn extract_name(meta: &syn::Meta, ident: &str) -> Result<Option<Ident>> {
match meta {
syn::Meta::Path(_) => Ok(None),
syn::Meta::NameValue(nv) => bail_spanned!(
nv.eq_token.span() => format!("expected `#[{}(name)]` to set the name", ident)
),
syn::Meta::List(l) => {
if let Ok(name) = l.parse_args::<syn::Ident>() {
Ok(Some(name))
} else if let Ok(name) = l.parse_args::<syn::LitStr>() {
name.parse().map(Some)
} else {
bail_spanned!(l.tokens.span() => "expected ident or string literal for property name");
}
}
}
}
let meta = &attr.meta;
let path = meta.path();
if path.is_ident("new") {
ensure_no_arguments(meta, "new")?;
Ok(Some(MethodTypeAttribute::New(path.span())))
} else if path.is_ident("__new__") {
let span = path.span();
deprecations.push(Deprecation::PyMethodsNewDeprecatedForm, span);
ensure_no_arguments(meta, "__new__")?;
Ok(Some(MethodTypeAttribute::New(span)))
} else if path.is_ident("classmethod") {
ensure_no_arguments(meta, "classmethod")?;
Ok(Some(MethodTypeAttribute::ClassMethod(path.span())))
} else if path.is_ident("staticmethod") {
ensure_no_arguments(meta, "staticmethod")?;
Ok(Some(MethodTypeAttribute::StaticMethod(path.span())))
} else if path.is_ident("classattr") {
ensure_no_arguments(meta, "classattr")?;
Ok(Some(MethodTypeAttribute::ClassAttribute(path.span())))
} else if path.is_ident("getter") {
let name = extract_name(meta, "getter")?;
Ok(Some(MethodTypeAttribute::Getter(path.span(), name)))
} else if path.is_ident("setter") {
let name = extract_name(meta, "setter")?;
Ok(Some(MethodTypeAttribute::Setter(path.span(), name)))
} else {
Ok(None)
}
}
}
impl Display for MethodTypeAttribute {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match self {
MethodTypeAttribute::New(_) => "#[new]".fmt(f),
MethodTypeAttribute::ClassMethod(_) => "#[classmethod]".fmt(f),
MethodTypeAttribute::StaticMethod(_) => "#[staticmethod]".fmt(f),
MethodTypeAttribute::Getter(_, _) => "#[getter]".fmt(f),
MethodTypeAttribute::Setter(_, _) => "#[setter]".fmt(f),
MethodTypeAttribute::ClassAttribute(_) => "#[classattr]".fmt(f),
}
}
}
fn parse_method_attributes(
attrs: &mut Vec<syn::Attribute>,
deprecations: &mut Deprecations<'_>,
) -> Result<Vec<MethodTypeAttribute>> {
let mut new_attrs = Vec::new();
let mut found_attrs = Vec::new();
for attr in attrs.drain(..) {
match MethodTypeAttribute::parse_if_matching_attribute(&attr, deprecations)? {
Some(attr) => found_attrs.push(attr),
None => new_attrs.push(attr),
}
}
*attrs = new_attrs;
Ok(found_attrs)
}
const IMPL_TRAIT_ERR: &str = "Python functions cannot have `impl Trait` arguments";
const RECEIVER_BY_VALUE_ERR: &str =
"Python objects are shared, so 'self' cannot be moved out of the Python interpreter.
Try `&self`, `&mut self, `slf: PyRef<'_, Self>` or `slf: PyRefMut<'_, Self>`.";
fn ensure_signatures_on_valid_method(
fn_type: &FnType,
signature: Option<&SignatureAttribute>,
text_signature: Option<&TextSignatureAttribute>,
) -> syn::Result<()> {
if let Some(signature) = signature {
match fn_type {
FnType::Getter(_) => {
bail_spanned!(signature.kw.span() => "`signature` not allowed with `getter`")
}
FnType::Setter(_) => {
bail_spanned!(signature.kw.span() => "`signature` not allowed with `setter`")
}
FnType::ClassAttribute => {
bail_spanned!(signature.kw.span() => "`signature` not allowed with `classattr`")
}
_ => {}
}
}
if let Some(text_signature) = text_signature {
match fn_type {
FnType::Getter(_) => {
bail_spanned!(text_signature.kw.span() => "`text_signature` not allowed with `getter`")
}
FnType::Setter(_) => {
bail_spanned!(text_signature.kw.span() => "`text_signature` not allowed with `setter`")
}
FnType::ClassAttribute => {
bail_spanned!(text_signature.kw.span() => "`text_signature` not allowed with `classattr`")
}
_ => {}
}
}
Ok(())
}