Skip to content

Update for generator resume arguments #34

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Mar 20, 2020
Merged

Update for generator resume arguments #34

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
7 changes: 5 additions & 2 deletions futures-async-stream-macro/src/stream.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -290,7 +290,7 @@ pub(super) fn make_gen_body(
#[allow(unreachable_code)]
{
return #ret_value;
loop { yield ::futures_async_stream::reexport::task::Poll::Pending }
loop { __task_context = yield ::futures_async_stream::reexport::task::Poll::Pending }
}
};
let mut gen_body = TokenStream::new();
Expand All @@ -299,7 +299,10 @@ pub(super) fn make_gen_body(
});

quote! {
#gen_function(static move || -> #ret_ty #gen_body)
#gen_function(
static move |mut __task_context: ::futures_async_stream::future::ResumeTy| -> #ret_ty
#gen_body
)
}
}

Expand Down
13 changes: 0 additions & 13 deletions futures-async-stream-macro/src/utils.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -50,19 +50,6 @@ where
*this = f(mem::replace(this, Expr::Verbatim(TokenStream::new())));
}

pub(super) fn replace_boxed_expr<F>(expr: &mut Option<Box<Expr>>, f: F)
where
F: FnOnce(Expr) -> Expr,
{
if expr.is_none() {
expr.replace(Box::new(unit()));
}

if let Some(expr) = expr {
replace_expr(&mut **expr, f);
}
}

macro_rules! error {
($span:expr, $msg:expr) => {
syn::Error::new_spanned($span, $msg)
Expand Down
36 changes: 21 additions & 15 deletions futures-async-stream-macro/src/visitor.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -8,7 +8,7 @@ use syn::{

use crate::{
async_stream_block, async_try_stream_block,
utils::{expr_compile_error, replace_boxed_expr, replace_expr},
utils::{expr_compile_error, replace_expr, unit},
};

pub(crate) use Scope::{Closure, Future, Stream, TryStream};
Expand Down Expand Up @@ -88,17 +88,18 @@ impl Visitor {
}
Stream | TryStream => {
quote! {
match ::futures_async_stream::stream::poll_next_with_tls_context(
match unsafe { ::futures_async_stream::stream::poll_next_with_context(
::futures_async_stream::reexport::pin::Pin::as_mut(&mut __pinned),
) {
__task_context,
) } {
::futures_async_stream::reexport::task::Poll::Ready(
::futures_async_stream::reexport::option::Option::Some(e),
) => e,
::futures_async_stream::reexport::task::Poll::Ready(
::futures_async_stream::reexport::option::Option::None,
) => break,
::futures_async_stream::reexport::task::Poll::Pending => {
yield ::futures_async_stream::reexport::task::Poll::Pending;
__task_context = yield ::futures_async_stream::reexport::task::Poll::Pending;
continue
}
}
Expand Down Expand Up @@ -129,17 +130,21 @@ impl Visitor {
}

/// Visits `yield <expr>` in `async_stream` scope.
fn visit_yield(&self, expr: &mut ExprYield) {
fn visit_yield(&self, expr: &mut Expr) {
if !self.scope.is_stream() {
return;
}

// Desugar `yield <expr>` into `yield Poll::Ready(<expr>)`.
replace_boxed_expr(&mut expr.expr, |expr| {
syn::parse_quote! {
::futures_async_stream::reexport::task::Poll::Ready(#expr)
// Desugar `yield <expr>` into `__task_context = yield Poll::Ready(<expr>)`.
if let Expr::Yield(ExprYield { yield_token, expr: e, .. }) = expr {
if e.is_none() {
e.replace(Box::new(unit()));
}
});

*expr = syn::parse_quote!(
__task_context = #yield_token ::futures_async_stream::reexport::task::Poll::Ready(#e)
);
}
}

/// Visits `async_stream_block!` macro.
Expand Down Expand Up @@ -176,14 +181,15 @@ impl Visitor {
let mut __pinned = #base;
loop {
if let ::futures_async_stream::reexport::task::Poll::Ready(x) =
::futures_async_stream::future::poll_with_tls_context(unsafe {
::futures_async_stream::reexport::pin::Pin::new_unchecked(&mut __pinned)
})
unsafe { ::futures_async_stream::future::poll_with_context(
::futures_async_stream::reexport::pin::Pin::new_unchecked(&mut __pinned),
__task_context,
)}
{
break x;
}

yield ::futures_async_stream::reexport::task::Poll::Pending
__task_context = yield ::futures_async_stream::reexport::task::Poll::Pending;
}
}})
.unwrap();
Expand Down Expand Up @@ -211,7 +217,7 @@ impl VisitMut for Visitor {

visit_mut::visit_expr_mut(self, expr);
match expr {
Expr::Yield(expr) => self.visit_yield(expr),
Expr::Yield(_) => self.visit_yield(expr),
Expr::Await(_) => self.visit_await(expr),
Expr::ForLoop(_) => self.visit_for_loop(expr),
Expr::Macro(_) => self.visit_macro(expr),
Expand Down
Loading