diff options
Diffstat (limited to 'tests/ui/async-await/multiple-lifetimes')
11 files changed, 238 insertions, 0 deletions
diff --git a/tests/ui/async-await/multiple-lifetimes/elided.rs b/tests/ui/async-await/multiple-lifetimes/elided.rs new file mode 100644 index 000000000..8258e2eff --- /dev/null +++ b/tests/ui/async-await/multiple-lifetimes/elided.rs @@ -0,0 +1,10 @@ +// edition:2018 +// run-pass + +// Test that we can use async fns with multiple arbitrary lifetimes. + +async fn multiple_elided_lifetimes(_: &u8, _: &u8) {} + +fn main() { + let _ = multiple_elided_lifetimes(&22, &44); +} diff --git a/tests/ui/async-await/multiple-lifetimes/fn-ptr.rs b/tests/ui/async-await/multiple-lifetimes/fn-ptr.rs new file mode 100644 index 000000000..3912b8547 --- /dev/null +++ b/tests/ui/async-await/multiple-lifetimes/fn-ptr.rs @@ -0,0 +1,12 @@ +// edition:2018 +// run-pass + +// Test that we can use async fns with multiple arbitrary lifetimes. + +async fn multiple_named_lifetimes<'a, 'b>(_: &'a u8, _: &'b u8, _: fn(&u8)) {} + +fn gimme(_: &u8) { } + +fn main() { + let _ = multiple_named_lifetimes(&22, &44, gimme); +} diff --git a/tests/ui/async-await/multiple-lifetimes/hrtb.rs b/tests/ui/async-await/multiple-lifetimes/hrtb.rs new file mode 100644 index 000000000..e788ca5ff --- /dev/null +++ b/tests/ui/async-await/multiple-lifetimes/hrtb.rs @@ -0,0 +1,14 @@ +// edition:2018 +// check-pass + +// Test that we can use async fns with multiple arbitrary lifetimes. + +use std::ops::Add; + +async fn multiple_hrtb_and_single_named_lifetime_ok<'c>( + _: impl for<'a> Add<&'a u8>, + _: impl for<'b> Add<&'b u8>, + _: &'c u8, +) {} + +fn main() {} diff --git a/tests/ui/async-await/multiple-lifetimes/named.rs b/tests/ui/async-await/multiple-lifetimes/named.rs new file mode 100644 index 000000000..e8eb98102 --- /dev/null +++ b/tests/ui/async-await/multiple-lifetimes/named.rs @@ -0,0 +1,10 @@ +// edition:2018 +// run-pass + +// Test that we can use async fns with multiple arbitrary lifetimes. + +async fn multiple_named_lifetimes<'a, 'b>(_: &'a u8, _: &'b u8) {} + +fn main() { + let _ = multiple_named_lifetimes(&22, &44); +} diff --git a/tests/ui/async-await/multiple-lifetimes/partial-relation.rs b/tests/ui/async-await/multiple-lifetimes/partial-relation.rs new file mode 100644 index 000000000..02b105999 --- /dev/null +++ b/tests/ui/async-await/multiple-lifetimes/partial-relation.rs @@ -0,0 +1,13 @@ +// edition:2018 +// run-pass + +async fn lotsa_lifetimes<'a, 'b, 'c>(a: &'a u32, b: &'b u32, c: &'c u32) -> (&'a u32, &'b u32) + where 'b: 'a +{ + drop((a, c)); + (b, b) +} + +fn main() { + let _ = lotsa_lifetimes(&22, &44, &66); +} diff --git a/tests/ui/async-await/multiple-lifetimes/ret-impl-trait-fg.rs b/tests/ui/async-await/multiple-lifetimes/ret-impl-trait-fg.rs new file mode 100644 index 000000000..f1002947f --- /dev/null +++ b/tests/ui/async-await/multiple-lifetimes/ret-impl-trait-fg.rs @@ -0,0 +1,17 @@ +// edition:2018 +// run-pass + +// Test member constraints that appear in the `impl Trait` +// return type of an async function. +// (This used to require a feature gate.) + +trait Trait<'a, 'b> { } +impl<T> Trait<'_, '_> for T { } + +async fn async_ret_impl_trait<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<'a, 'b> { + (a, b) +} + +fn main() { + let _ = async_ret_impl_trait(&22, &44); +} diff --git a/tests/ui/async-await/multiple-lifetimes/ret-impl-trait-one.rs b/tests/ui/async-await/multiple-lifetimes/ret-impl-trait-one.rs new file mode 100644 index 000000000..aebc77d26 --- /dev/null +++ b/tests/ui/async-await/multiple-lifetimes/ret-impl-trait-one.rs @@ -0,0 +1,31 @@ +// edition:2018 + +// Test that a feature gate is needed to use `impl Trait` as the +// return type of an async. + +trait Trait<'a> { } +impl<T> Trait<'_> for T { } + +// Fails to recognize that both 'a and 'b are mentioned and should thus be accepted +async fn async_ret_impl_trait3<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<'a> + 'b { + //~^ ERROR lifetime may not live long enough + (a, b) +} + +// Only `'a` permitted in return type, not `'b`. +async fn async_ret_impl_trait1<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<'a> { + //~^ ERROR captures lifetime that does not appear in bounds + (a, b) +} + +// As above, but `'b: 'a`, so return type can be inferred to `(&'a u8, +// &'a u8)`. +async fn async_ret_impl_trait2<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<'a> +where + 'b: 'a, +{ + (a, b) +} + +fn main() { +} diff --git a/tests/ui/async-await/multiple-lifetimes/ret-impl-trait-one.stderr b/tests/ui/async-await/multiple-lifetimes/ret-impl-trait-one.stderr new file mode 100644 index 000000000..ae4d0d585 --- /dev/null +++ b/tests/ui/async-await/multiple-lifetimes/ret-impl-trait-one.stderr @@ -0,0 +1,35 @@ +error: lifetime may not live long enough + --> $DIR/ret-impl-trait-one.rs:10:85 + | +LL | async fn async_ret_impl_trait3<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<'a> + 'b { + | ________________________________--__--_______________________________________________^ + | | | | + | | | lifetime `'b` defined here + | | lifetime `'a` defined here +LL | | +LL | | (a, b) +LL | | } + | |_^ function was supposed to return data with lifetime `'b` but it is returning data with lifetime `'a` + | + = help: consider adding the following bound: `'a: 'b` + +error[E0700]: hidden type for `impl Trait<'a>` captures lifetime that does not appear in bounds + --> $DIR/ret-impl-trait-one.rs:16:80 + | +LL | async fn async_ret_impl_trait1<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<'a> { + | ____________________________________--__________________________________________^ + | | | + | | hidden type `(&'a u8, &'b u8)` captures the lifetime `'b` as defined here +LL | | +LL | | (a, b) +LL | | } + | |_^ + | +help: to declare that `impl Trait<'a>` captures `'b`, you can add an explicit `'b` lifetime bound + | +LL | async fn async_ret_impl_trait1<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<'a> + 'b { + | ++++ + +error: aborting due to 2 previous errors + +For more information about this error, try `rustc --explain E0700`. diff --git a/tests/ui/async-await/multiple-lifetimes/ret-ref.rs b/tests/ui/async-await/multiple-lifetimes/ret-ref.rs new file mode 100644 index 000000000..149c020f9 --- /dev/null +++ b/tests/ui/async-await/multiple-lifetimes/ret-ref.rs @@ -0,0 +1,44 @@ +// edition:2018 + +// Test that we get the expected borrow check errors when an async +// function (which takes multiple lifetimes) only returns data from +// one of them. + +async fn multiple_named_lifetimes<'a, 'b>(a: &'a u8, _: &'b u8) -> &'a u8 { + a +} + +// Both are borrowed whilst the future is live. +async fn future_live() { + let mut a = 22; + let mut b = 44; + let future = multiple_named_lifetimes(&a, &b); + a += 1; //~ ERROR cannot assign + b += 1; //~ ERROR cannot assign + let p = future.await; + drop(p); +} + +// Just the return value is live after future is awaited. +async fn just_return_live() { + let mut a = 22; + let mut b = 44; + let future = multiple_named_lifetimes(&a, &b); + let p = future.await; + a += 1; //~ ERROR cannot assign + b += 1; + drop(p); +} + +// Once `p` is dead, both `a` and `b` are unborrowed. +async fn after_both_dead() { + let mut a = 22; + let mut b = 44; + let future = multiple_named_lifetimes(&a, &b); + let p = future.await; + drop(p); + a += 1; + b += 1; +} + +fn main() { } diff --git a/tests/ui/async-await/multiple-lifetimes/ret-ref.stderr b/tests/ui/async-await/multiple-lifetimes/ret-ref.stderr new file mode 100644 index 000000000..d86e84033 --- /dev/null +++ b/tests/ui/async-await/multiple-lifetimes/ret-ref.stderr @@ -0,0 +1,37 @@ +error[E0506]: cannot assign to `a` because it is borrowed + --> $DIR/ret-ref.rs:16:5 + | +LL | let future = multiple_named_lifetimes(&a, &b); + | -- borrow of `a` occurs here +LL | a += 1; + | ^^^^^^ assignment to borrowed `a` occurs here +LL | b += 1; +LL | let p = future.await; + | ------ borrow later used here + +error[E0506]: cannot assign to `b` because it is borrowed + --> $DIR/ret-ref.rs:17:5 + | +LL | let future = multiple_named_lifetimes(&a, &b); + | -- borrow of `b` occurs here +LL | a += 1; +LL | b += 1; + | ^^^^^^ assignment to borrowed `b` occurs here +LL | let p = future.await; + | ------ borrow later used here + +error[E0506]: cannot assign to `a` because it is borrowed + --> $DIR/ret-ref.rs:28:5 + | +LL | let future = multiple_named_lifetimes(&a, &b); + | -- borrow of `a` occurs here +LL | let p = future.await; +LL | a += 1; + | ^^^^^^ assignment to borrowed `a` occurs here +LL | b += 1; +LL | drop(p); + | - borrow later used here + +error: aborting due to 3 previous errors + +For more information about this error, try `rustc --explain E0506`. diff --git a/tests/ui/async-await/multiple-lifetimes/variance.rs b/tests/ui/async-await/multiple-lifetimes/variance.rs new file mode 100644 index 000000000..6ed8bef95 --- /dev/null +++ b/tests/ui/async-await/multiple-lifetimes/variance.rs @@ -0,0 +1,15 @@ +// edition:2018 +// run-pass + +// Test for async fn where the parameters have distinct lifetime +// parameters that appear in all possible variances. + +async fn lotsa_lifetimes<'a, 'b, 'c>(_: fn(&'a u8), _: fn(&'b u8) -> &'b u8, _: fn() -> &'c u8) { } + +fn take_any(_: &u8) { } +fn identify(x: &u8) -> &u8 { x } +fn give_back() -> &'static u8 { &22 } + +fn main() { + let _ = lotsa_lifetimes(take_any, identify, give_back); +} |