diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs index 084091f4c2a39..60f685859eee3 100644 --- a/src/libsyntax/parse/parser.rs +++ b/src/libsyntax/parse/parser.rs @@ -1576,7 +1576,7 @@ impl<'a> Parser<'a> { let ident = self.parse_ident()?; let mut generics = self.parse_generics()?; - let d = self.parse_fn_decl_with_self(|p: &mut Parser<'a>| { + let mut decl = self.parse_fn_decl_with_self(|p: &mut Parser<'a>| { // This is somewhat dubious; We don't want to allow // argument names to be left off if there is a // definition... @@ -1585,7 +1585,7 @@ impl<'a> Parser<'a> { p.parse_arg_general(p.span.rust_2018(), true, false) })?; generics.where_clause = self.parse_where_clause()?; - self.construct_async_arguments(&mut asyncness, &d); + self.construct_async_arguments(&mut asyncness, &mut decl); let sig = ast::MethodSig { header: FnHeader { @@ -1594,7 +1594,7 @@ impl<'a> Parser<'a> { abi, asyncness, }, - decl: d, + decl, }; let body = match self.token { @@ -6475,10 +6475,10 @@ impl<'a> Parser<'a> { -> PResult<'a, ItemInfo> { let (ident, mut generics) = self.parse_fn_header()?; let allow_c_variadic = abi == Abi::C && unsafety == Unsafety::Unsafe; - let decl = self.parse_fn_decl(allow_c_variadic)?; + let mut decl = self.parse_fn_decl(allow_c_variadic)?; generics.where_clause = self.parse_where_clause()?; let (inner_attrs, body) = self.parse_inner_attrs_and_block()?; - self.construct_async_arguments(&mut asyncness, &decl); + self.construct_async_arguments(&mut asyncness, &mut decl); let header = FnHeader { unsafety, asyncness, constness, abi }; Ok((ident, ItemKind::Fn(decl, header, generics, body), Some(inner_attrs))) } @@ -6662,9 +6662,9 @@ impl<'a> Parser<'a> { let (constness, unsafety, mut asyncness, abi) = self.parse_fn_front_matter()?; let ident = self.parse_ident()?; let mut generics = self.parse_generics()?; - let decl = self.parse_fn_decl_with_self(|p| p.parse_arg())?; + let mut decl = self.parse_fn_decl_with_self(|p| p.parse_arg())?; generics.where_clause = self.parse_where_clause()?; - self.construct_async_arguments(&mut asyncness, &decl); + self.construct_async_arguments(&mut asyncness, &mut decl); *at_end = true; let (inner_attrs, body) = self.parse_inner_attrs_and_block()?; let header = ast::FnHeader { abi, unsafety, constness, asyncness }; @@ -8710,9 +8710,9 @@ impl<'a> Parser<'a> { /// /// The arguments of the function are replaced in HIR lowering with the arguments created by /// this function and the statements created here are inserted at the top of the closure body. - fn construct_async_arguments(&mut self, asyncness: &mut Spanned, decl: &FnDecl) { + fn construct_async_arguments(&mut self, asyncness: &mut Spanned, decl: &mut FnDecl) { if let IsAsync::Async { ref mut arguments, .. } = asyncness.node { - for (index, input) in decl.inputs.iter().enumerate() { + for (index, input) in decl.inputs.iter_mut().enumerate() { let id = ast::DUMMY_NODE_ID; let span = input.pat.span; @@ -8724,8 +8724,10 @@ impl<'a> Parser<'a> { // `let = __argN;` statement, instead just adding a `let = ;` // statement. let (binding_mode, ident, is_simple_pattern) = match input.pat.node { - PatKind::Ident(binding_mode, ident, _) => (binding_mode, ident, true), - _ => (BindingMode::ByValue(Mutability::Immutable), ident, false), + PatKind::Ident(binding_mode @ BindingMode::ByValue(_), ident, _) => { + (binding_mode, ident, true) + } + _ => (BindingMode::ByValue(Mutability::Mutable), ident, false), }; // Construct an argument representing `__argN: ` to replace the argument of the @@ -8792,6 +8794,15 @@ impl<'a> Parser<'a> { }) }; + // Remove mutability from arguments. If this is not a simple pattern, + // those arguments are replaced by `__argN`, so there is no need to do this. + if let PatKind::Ident(BindingMode::ByValue(mutability @ Mutability::Mutable), ..) = + &mut input.pat.node + { + assert!(is_simple_pattern); + *mutability = Mutability::Immutable; + } + let move_stmt = Stmt { id, node: StmtKind::Local(P(move_local)), span }; arguments.push(AsyncArgument { ident, arg, pat_stmt, move_stmt }); } diff --git a/src/test/ui/async-await/argument-patterns.rs b/src/test/ui/async-await/argument-patterns.rs new file mode 100644 index 0000000000000..3750c2bcb701a --- /dev/null +++ b/src/test/ui/async-await/argument-patterns.rs @@ -0,0 +1,30 @@ +// edition:2018 +// run-pass + +#![allow(unused_variables)] +#![deny(unused_mut)] +#![feature(async_await)] + +type A = Vec; + +async fn a(n: u32, mut vec: A) { + vec.push(n); +} + +async fn b(n: u32, ref mut vec: A) { + vec.push(n); +} + +async fn c(ref vec: A) { + vec.contains(&0); +} + +async fn d((a, mut b): (A, A)) { + b.push(1); +} + +async fn f((ref mut a, ref b): (A, A)) {} + +async fn g(((ref a, ref mut b), (ref mut c, ref d)): ((A, A), (A, A))) {} + +fn main() {} diff --git a/src/test/ui/async-await/drop-order-for-async-fn-parameters-by-ref-binding.rs b/src/test/ui/async-await/drop-order-for-async-fn-parameters-by-ref-binding.rs new file mode 100644 index 0000000000000..c2b59eecb9993 --- /dev/null +++ b/src/test/ui/async-await/drop-order-for-async-fn-parameters-by-ref-binding.rs @@ -0,0 +1,271 @@ +// aux-build:arc_wake.rs +// edition:2018 +// run-pass + +#![allow(unused_variables)] +#![feature(async_await, await_macro)] + +// Test that the drop order for parameters in a fn and async fn matches up. Also test that +// parameters (used or unused) are not dropped until the async fn completes execution. +// See also #54716. + +extern crate arc_wake; + +use arc_wake::ArcWake; +use std::cell::RefCell; +use std::future::Future; +use std::marker::PhantomData; +use std::sync::Arc; +use std::rc::Rc; +use std::task::Context; + +struct EmptyWaker; + +impl ArcWake for EmptyWaker { + fn wake(self: Arc) {} +} + +#[derive(Debug, Eq, PartialEq)] +enum DropOrder { + Function, + Val(&'static str), +} + +type DropOrderListPtr = Rc>>; + +struct D(&'static str, DropOrderListPtr); + +impl Drop for D { + fn drop(&mut self) { + self.1.borrow_mut().push(DropOrder::Val(self.0)); + } +} + +/// Check that unused bindings are dropped after the function is polled. +async fn foo_async(ref mut x: D, ref mut _y: D) { + x.1.borrow_mut().push(DropOrder::Function); +} + +fn foo_sync(ref mut x: D, ref mut _y: D) { + x.1.borrow_mut().push(DropOrder::Function); +} + +/// Check that underscore patterns are dropped after the function is polled. +async fn bar_async(ref mut x: D, _: D) { + x.1.borrow_mut().push(DropOrder::Function); +} + +fn bar_sync(ref mut x: D, _: D) { + x.1.borrow_mut().push(DropOrder::Function); +} + +/// Check that underscore patterns within more complex patterns are dropped after the function +/// is polled. +async fn baz_async((ref mut x, _): (D, D)) { + x.1.borrow_mut().push(DropOrder::Function); +} + +fn baz_sync((ref mut x, _): (D, D)) { + x.1.borrow_mut().push(DropOrder::Function); +} + +/// Check that underscore and unused bindings within and outwith more complex patterns are dropped +/// after the function is polled. +async fn foobar_async(ref mut x: D, (ref mut a, _, ref mut _c): (D, D, D), _: D, ref mut _y: D) { + x.1.borrow_mut().push(DropOrder::Function); +} + +fn foobar_sync(ref mut x: D, (ref mut a, _, ref mut _c): (D, D, D), _: D, ref mut _y: D) { + x.1.borrow_mut().push(DropOrder::Function); +} + +struct Foo; + +impl Foo { + /// Check that unused bindings are dropped after the method is polled. + async fn foo_async(ref mut x: D, ref mut _y: D) { + x.1.borrow_mut().push(DropOrder::Function); + } + + fn foo_sync(ref mut x: D, ref mut _y: D) { + x.1.borrow_mut().push(DropOrder::Function); + } + + /// Check that underscore patterns are dropped after the method is polled. + async fn bar_async(ref mut x: D, _: D) { + x.1.borrow_mut().push(DropOrder::Function); + } + + fn bar_sync(ref mut x: D, _: D) { + x.1.borrow_mut().push(DropOrder::Function); + } + + /// Check that underscore patterns within more complex patterns are dropped after the method + /// is polled. + async fn baz_async((ref mut x, _): (D, D)) { + x.1.borrow_mut().push(DropOrder::Function); + } + + fn baz_sync((ref mut x, _): (D, D)) { + x.1.borrow_mut().push(DropOrder::Function); + } + + /// Check that underscore and unused bindings within and outwith more complex patterns are + /// dropped after the method is polled. + async fn foobar_async( + ref mut x: D, (ref mut a, _, ref mut _c): (D, D, D), _: D, ref mut _y: D, + ) { + x.1.borrow_mut().push(DropOrder::Function); + } + + fn foobar_sync( + ref mut x: D, (ref mut a, _, ref mut _c): (D, D, D), _: D, ref mut _y: D, + ) { + x.1.borrow_mut().push(DropOrder::Function); + } +} + +struct Bar<'a>(PhantomData<&'a ()>); + +impl<'a> Bar<'a> { + /// Check that unused bindings are dropped after the method with self is polled. + async fn foo_async(&'a self, ref mut x: D, ref mut _y: D) { + x.1.borrow_mut().push(DropOrder::Function); + } + + fn foo_sync(&'a self, ref mut x: D, ref mut _y: D) { + x.1.borrow_mut().push(DropOrder::Function); + } + + /// Check that underscore patterns are dropped after the method with self is polled. + async fn bar_async(&'a self, ref mut x: D, _: D) { + x.1.borrow_mut().push(DropOrder::Function); + } + + fn bar_sync(&'a self, ref mut x: D, _: D) { + x.1.borrow_mut().push(DropOrder::Function); + } + + /// Check that underscore patterns within more complex patterns are dropped after the method + /// with self is polled. + async fn baz_async(&'a self, (ref mut x, _): (D, D)) { + x.1.borrow_mut().push(DropOrder::Function); + } + + fn baz_sync(&'a self, (ref mut x, _): (D, D)) { + x.1.borrow_mut().push(DropOrder::Function); + } + + /// Check that underscore and unused bindings within and outwith more complex patterns are + /// dropped after the method with self is polled. + async fn foobar_async( + &'a self, ref mut x: D, (ref mut a, _, ref mut _c): (D, D, D), _: D, ref mut _y: D, + ) { + x.1.borrow_mut().push(DropOrder::Function); + } + + fn foobar_sync( + &'a self, ref mut x: D, (ref mut a, _, ref mut _c): (D, D, D), _: D, ref mut _y: D, + ) { + x.1.borrow_mut().push(DropOrder::Function); + } +} + +fn assert_drop_order_after_poll>( + f: impl FnOnce(DropOrderListPtr) -> Fut, + g: impl FnOnce(DropOrderListPtr), +) { + let empty = Arc::new(EmptyWaker); + let waker = ArcWake::into_waker(empty); + let mut cx = Context::from_waker(&waker); + + let actual_order = Rc::new(RefCell::new(Vec::new())); + let mut fut = Box::pin(f(actual_order.clone())); + let _ = fut.as_mut().poll(&mut cx); + + let expected_order = Rc::new(RefCell::new(Vec::new())); + g(expected_order.clone()); + + assert_eq!(*actual_order.borrow(), *expected_order.borrow()); +} + +fn main() { + // Free functions (see doc comment on function for what it tests). + assert_drop_order_after_poll(|l| foo_async(D("x", l.clone()), D("_y", l.clone())), + |l| foo_sync(D("x", l.clone()), D("_y", l.clone()))); + assert_drop_order_after_poll(|l| bar_async(D("x", l.clone()), D("_", l.clone())), + |l| bar_sync(D("x", l.clone()), D("_", l.clone()))); + assert_drop_order_after_poll(|l| baz_async((D("x", l.clone()), D("_", l.clone()))), + |l| baz_sync((D("x", l.clone()), D("_", l.clone())))); + assert_drop_order_after_poll( + |l| { + foobar_async( + D("x", l.clone()), + (D("a", l.clone()), D("_", l.clone()), D("_c", l.clone())), + D("_", l.clone()), + D("_y", l.clone()), + ) + }, + |l| { + foobar_sync( + D("x", l.clone()), + (D("a", l.clone()), D("_", l.clone()), D("_c", l.clone())), + D("_", l.clone()), + D("_y", l.clone()), + ) + }, + ); + + // Methods w/out self (see doc comment on function for what it tests). + assert_drop_order_after_poll(|l| Foo::foo_async(D("x", l.clone()), D("_y", l.clone())), + |l| Foo::foo_sync(D("x", l.clone()), D("_y", l.clone()))); + assert_drop_order_after_poll(|l| Foo::bar_async(D("x", l.clone()), D("_", l.clone())), + |l| Foo::bar_sync(D("x", l.clone()), D("_", l.clone()))); + assert_drop_order_after_poll(|l| Foo::baz_async((D("x", l.clone()), D("_", l.clone()))), + |l| Foo::baz_sync((D("x", l.clone()), D("_", l.clone())))); + assert_drop_order_after_poll( + |l| { + Foo::foobar_async( + D("x", l.clone()), + (D("a", l.clone()), D("_", l.clone()), D("_c", l.clone())), + D("_", l.clone()), + D("_y", l.clone()), + ) + }, + |l| { + Foo::foobar_sync( + D("x", l.clone()), + (D("a", l.clone()), D("_", l.clone()), D("_c", l.clone())), + D("_", l.clone()), + D("_y", l.clone()), + ) + }, + ); + + // Methods (see doc comment on function for what it tests). + let b = Bar(Default::default()); + assert_drop_order_after_poll(|l| b.foo_async(D("x", l.clone()), D("_y", l.clone())), + |l| b.foo_sync(D("x", l.clone()), D("_y", l.clone()))); + assert_drop_order_after_poll(|l| b.bar_async(D("x", l.clone()), D("_", l.clone())), + |l| b.bar_sync(D("x", l.clone()), D("_", l.clone()))); + assert_drop_order_after_poll(|l| b.baz_async((D("x", l.clone()), D("_", l.clone()))), + |l| b.baz_sync((D("x", l.clone()), D("_", l.clone())))); + assert_drop_order_after_poll( + |l| { + b.foobar_async( + D("x", l.clone()), + (D("a", l.clone()), D("_", l.clone()), D("_c", l.clone())), + D("_", l.clone()), + D("_y", l.clone()), + ) + }, + |l| { + b.foobar_sync( + D("x", l.clone()), + (D("a", l.clone()), D("_", l.clone()), D("_c", l.clone())), + D("_", l.clone()), + D("_y", l.clone()), + ) + }, + ); +} diff --git a/src/test/ui/async-await/drop-order-locals-are-hidden.rs b/src/test/ui/async-await/drop-order-locals-are-hidden.rs index 10dc5e27f6f9f..bcdb8878eb5d2 100644 --- a/src/test/ui/async-await/drop-order-locals-are-hidden.rs +++ b/src/test/ui/async-await/drop-order-locals-are-hidden.rs @@ -8,4 +8,9 @@ async fn foobar_async(x: u32, (a, _, _c): (u32, u32, u32), _: u32, _y: u32) { assert_eq!(__arg2, 4); //~ ERROR cannot find value `__arg2` in this scope [E0425] } +async fn baz_async(ref mut x: u32, ref y: u32) { + assert_eq!(__arg0, 1); //~ ERROR cannot find value `__arg0` in this scope [E0425] + assert_eq!(__arg1, 2); //~ ERROR cannot find value `__arg1` in this scope [E0425] +} + fn main() {} diff --git a/src/test/ui/async-await/drop-order-locals-are-hidden.stderr b/src/test/ui/async-await/drop-order-locals-are-hidden.stderr index ca0da6b7c962a..484e1f4f4269e 100644 --- a/src/test/ui/async-await/drop-order-locals-are-hidden.stderr +++ b/src/test/ui/async-await/drop-order-locals-are-hidden.stderr @@ -10,6 +10,18 @@ error[E0425]: cannot find value `__arg2` in this scope LL | assert_eq!(__arg2, 4); | ^^^^^^ not found in this scope -error: aborting due to 2 previous errors +error[E0425]: cannot find value `__arg0` in this scope + --> $DIR/drop-order-locals-are-hidden.rs:12:16 + | +LL | assert_eq!(__arg0, 1); + | ^^^^^^ not found in this scope + +error[E0425]: cannot find value `__arg1` in this scope + --> $DIR/drop-order-locals-are-hidden.rs:13:16 + | +LL | assert_eq!(__arg1, 2); + | ^^^^^^ not found in this scope + +error: aborting due to 4 previous errors For more information about this error, try `rustc --explain E0425`. diff --git a/src/test/ui/async-await/mutable-arguments.rs b/src/test/ui/async-await/mutable-arguments.rs deleted file mode 100644 index 4d6dba74097ca..0000000000000 --- a/src/test/ui/async-await/mutable-arguments.rs +++ /dev/null @@ -1,10 +0,0 @@ -// edition:2018 -// run-pass - -#![feature(async_await)] - -async fn foo(n: u32, mut vec: Vec) { - vec.push(n); -} - -fn main() {}