Implement in-band lifetime bindings

src/test/ui/in-band-lifetimes/E0687.rs

@@ -0,0 +1,26 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![allow(warnings)]
+#![feature(in_band_lifetimes)]
+
+fn foo(x: fn(&'a u32)) {}
+
+fn bar(x: &Fn(&'a u32)) {}
+
+fn baz(x: fn(&'a u32), y: &'a u32) {}
+
+struct Foo<'a> { x: &'a u32 }
+
+impl Foo<'a> {
+    fn bar(&self, x: fn(&'a u32)) {}
+}
+
+fn main() {}

src/test/ui/in-band-lifetimes/E0687.stderr

@@ -0,0 +1,26 @@
+error[E0687]: lifetimes used in `fn` or `Fn` syntax must be explicitly declared using `<...>` binders
+  --> $DIR/E0687.rs:14:15
+   |
+14 | fn foo(x: fn(&'a u32)) {}
+   |               ^^ in-band lifetime definition
+
+error[E0687]: lifetimes used in `fn` or `Fn` syntax must be explicitly declared using `<...>` binders
+  --> $DIR/E0687.rs:16:16
+   |
+16 | fn bar(x: &Fn(&'a u32)) {}
+   |                ^^ in-band lifetime definition
+
+error[E0687]: lifetimes used in `fn` or `Fn` syntax must be explicitly declared using `<...>` binders
+  --> $DIR/E0687.rs:18:15
+   |
+18 | fn baz(x: fn(&'a u32), y: &'a u32) {}
+   |               ^^ in-band lifetime definition
+
+error[E0687]: lifetimes used in `fn` or `Fn` syntax must be explicitly declared using `<...>` binders
+  --> $DIR/E0687.rs:23:26
+   |
+23 |     fn bar(&self, x: fn(&'a u32)) {}
+   |                          ^^ in-band lifetime definition
+
+error: aborting due to 4 previous errors
+

src/test/ui/in-band-lifetimes/E0687_where.rs

@@ -0,0 +1,18 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![allow(warnings)]
+#![feature(in_band_lifetimes, universal_impl_trait)]
+
+fn bar<F>(x: &F) where F: Fn(&'a u32) {}
+
+fn baz(x: &impl Fn(&'a u32)) {}
+
+fn main() {}

src/test/ui/in-band-lifetimes/E0687_where.stderr

@@ -0,0 +1,14 @@
+error[E0687]: lifetimes used in `fn` or `Fn` syntax must be explicitly declared using `<...>` binders
+  --> $DIR/E0687_where.rs:14:31
+   |
+14 | fn bar<F>(x: &F) where F: Fn(&'a u32) {}
+   |                               ^^ in-band lifetime definition
+
+error[E0687]: lifetimes used in `fn` or `Fn` syntax must be explicitly declared using `<...>` binders
+  --> $DIR/E0687_where.rs:16:21
+   |
+16 | fn baz(x: &impl Fn(&'a u32)) {}
+   |                     ^^ in-band lifetime definition
+
+error: aborting due to 2 previous errors
+

src/test/ui/in-band-lifetimes/E0688.rs

@@ -0,0 +1,26 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![allow(warnings)]
+#![feature(in_band_lifetimes)]
+
+fn foo<'a>(x: &'a u32, y: &'b u32) {}
+
+struct Foo<'a> { x: &'a u32 }
+
+impl Foo<'a> {
+    fn bar<'b>(x: &'a u32, y: &'b u32, z: &'c u32) {}
+}
+
+impl<'b> Foo<'a> {
+    fn baz() {}
+}
+
+fn main() {}

src/test/ui/in-band-lifetimes/E0688.stderr

@@ -0,0 +1,26 @@
+error[E0688]: cannot mix in-band and explicit lifetime definitions
+  --> $DIR/E0688.rs:14:28
+   |
+14 | fn foo<'a>(x: &'a u32, y: &'b u32) {}
+   |        --                  ^^ in-band lifetime definition here
+   |        |
+   |        explicit lifetime definition here
+
+error[E0688]: cannot mix in-band and explicit lifetime definitions
+  --> $DIR/E0688.rs:19:44
+   |
+19 |     fn bar<'b>(x: &'a u32, y: &'b u32, z: &'c u32) {}
+   |            --                              ^^ in-band lifetime definition here
+   |            |
+   |            explicit lifetime definition here
+
+error[E0688]: cannot mix in-band and explicit lifetime definitions
+  --> $DIR/E0688.rs:22:14
+   |
+22 | impl<'b> Foo<'a> {
+   |      --      ^^ in-band lifetime definition here
+   |      |
+   |      explicit lifetime definition here
+
+error: aborting due to 3 previous errors
+

src/test/ui/in-band-lifetimes/mismatched.rs

@@ -0,0 +1,18 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![allow(warnings)]
+#![feature(in_band_lifetimes)]
+
+fn foo(x: &'a u32, y: &u32) -> &'a u32 { y }
+
+fn foo2(x: &'a u32, y: &'b u32) -> &'a u32 { y }
+
+fn main() {}

src/test/ui/in-band-lifetimes/mismatched.stderr

@@ -0,0 +1,18 @@
+error[E0621]: explicit lifetime required in the type of `y`
+  --> $DIR/mismatched.rs:14:42
+   |
+14 | fn foo(x: &'a u32, y: &u32) -> &'a u32 { y }
+   |                    -                     ^ lifetime `'a` required
+   |                    |
+   |                    consider changing the type of `y` to `&'a u32`
+
+error[E0623]: lifetime mismatch
+  --> $DIR/mismatched.rs:16:46
+   |
+16 | fn foo2(x: &'a u32, y: &'b u32) -> &'a u32 { y }
+   |                        -------     -------   ^ ...but data from `y` is returned here
+   |                        |
+   |                        this parameter and the return type are declared with different lifetimes...
+
+error: aborting due to 2 previous errors
+

src/test/ui/in-band-lifetimes/mismatched_trait.rs

@@ -0,0 +1,20 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![allow(warnings)]
+#![feature(in_band_lifetimes)]
+
+trait Get {
+    fn baz(&self, x: &'a u32, y: &u32) -> &'a u32 {
+        y
+    }
+}
+
+fn main() {}

src/test/ui/in-band-lifetimes/mismatched_trait.stderr

@@ -0,0 +1,10 @@
+error[E0621]: explicit lifetime required in the type of `y`
+  --> $DIR/mismatched_trait.rs:16:9
+   |
+15 |     fn baz(&self, x: &'a u32, y: &u32) -> &'a u32 {
+   |                               - consider changing the type of `y` to `&'a u32`
+16 |         y
+   |         ^ lifetime `'a` required
+
+error: aborting due to previous error
+

src/test/ui/in-band-lifetimes/mismatched_trait_impl.rs

@@ -0,0 +1,24 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![allow(warnings)]
+#![feature(in_band_lifetimes)]
+
+trait Get {
+    fn foo(&self, x: &'a u32, y: &u32) -> &'a u32;
+}
+
+impl Get for i32 {
+    fn foo(&self, x: &u32, y: &'a u32) -> &'a u32 {
+        x
+    }
+}
+
+fn main() {}

src/test/ui/in-band-lifetimes/mismatched_trait_impl.stderr

@@ -0,0 +1,39 @@
+error[E0495]: cannot infer an appropriate lifetime for lifetime parameter 'a in generic type due to conflicting requirements
+  --> $DIR/mismatched_trait_impl.rs:19:5
+   |
+19 | /     fn foo(&self, x: &u32, y: &'a u32) -> &'a u32 {
+20 | |         x
+21 | |     }
+   | |_____^
+   |
+note: first, the lifetime cannot outlive the anonymous lifetime #2 defined on the method body at 19:5...
+  --> $DIR/mismatched_trait_impl.rs:19:5
+   |
+19 | /     fn foo(&self, x: &u32, y: &'a u32) -> &'a u32 {
+20 | |         x
+21 | |     }
+   | |_____^
+note: ...so that method type is compatible with trait (expected fn(&i32, &'a u32, &u32) -> &'a u32, found fn(&i32, &u32, &u32) -> &u32)
+  --> $DIR/mismatched_trait_impl.rs:19:5
+   |
+19 | /     fn foo(&self, x: &u32, y: &'a u32) -> &'a u32 {
+20 | |         x
+21 | |     }
+   | |_____^
+note: but, the lifetime must be valid for the lifetime 'a as defined on the method body at 19:5...
+  --> $DIR/mismatched_trait_impl.rs:19:5
+   |
+19 | /     fn foo(&self, x: &u32, y: &'a u32) -> &'a u32 {
+20 | |         x
+21 | |     }
+   | |_____^
+note: ...so that method type is compatible with trait (expected fn(&i32, &'a u32, &u32) -> &'a u32, found fn(&i32, &u32, &u32) -> &u32)
+  --> $DIR/mismatched_trait_impl.rs:19:5
+   |
+19 | /     fn foo(&self, x: &u32, y: &'a u32) -> &'a u32 {
+20 | |         x
+21 | |     }
+   | |_____^
+
+error: aborting due to previous error
+

src/test/ui/in-band-lifetimes/mut_while_borrow.rs

@@ -0,0 +1,21 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![allow(warnings)]
+#![feature(in_band_lifetimes)]
+
+fn foo(x: &'a u32) -> &'a u32 { x }
+
+fn main() {
+    let mut p = 3;
+    let r = foo(&p);
+    p += 1;
+    println!("{}", r);
+}

src/test/ui/in-band-lifetimes/mut_while_borrow.stderr

@@ -0,0 +1,10 @@
+error[E0506]: cannot assign to `p` because it is borrowed
+  --> $DIR/mut_while_borrow.rs:19:5
+   |
+18 |     let r = foo(&p);
+   |                  - borrow of `p` occurs here
+19 |     p += 1;
+   |     ^^^^^^ assignment to borrowed `p` occurs here
+
+error: aborting due to previous error
+

src/test/ui/in-band-lifetimes/no_in_band_in_struct.rs

@@ -0,0 +1,22 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![allow(warnings)]
+#![feature(in_band_lifetimes)]
+
+struct Foo {
+    x: &'test u32,
+}
+
+enum Bar {
+    Baz(&'test u32),
+}
+
+fn main() {}

src/test/ui/in-band-lifetimes/no_in_band_in_struct.stderr

@@ -0,0 +1,14 @@
+error[E0261]: use of undeclared lifetime name `'test`
+  --> $DIR/no_in_band_in_struct.rs:15:9
+   |
+15 |     x: &'test u32,
+   |         ^^^^^ undeclared lifetime
+
+error[E0261]: use of undeclared lifetime name `'test`
+  --> $DIR/no_in_band_in_struct.rs:19:10
+   |
+19 |     Baz(&'test u32),
+   |          ^^^^^ undeclared lifetime
+
+error: aborting due to 2 previous errors
+

src/test/ui/in-band-lifetimes/no_introducing_in_band_in_locals.rs

@@ -0,0 +1,23 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![allow(warnings)]
+#![feature(in_band_lifetimes)]
+
+fn foo(x: &u32) {
+    let y: &'test u32 = x;
+}
+
+fn foo2(x: &u32) {}
+fn bar() {
+    let y: fn(&'test u32) = foo2;
+}
+
+fn main() {}

src/test/ui/in-band-lifetimes/no_introducing_in_band_in_locals.stderr

@@ -0,0 +1,14 @@
+error[E0261]: use of undeclared lifetime name `'test`
+  --> $DIR/no_introducing_in_band_in_locals.rs:15:13
+   |
+15 |     let y: &'test u32 = x;
+   |             ^^^^^ undeclared lifetime
+
+error[E0261]: use of undeclared lifetime name `'test`
+  --> $DIR/no_introducing_in_band_in_locals.rs:20:16
+   |
+20 |     let y: fn(&'test u32) = foo2;
+   |                ^^^^^ undeclared lifetime
+
+error: aborting due to 2 previous errors
+

src/test/ui/in-band-lifetimes/shadow.rs

@@ -0,0 +1,21 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![allow(warnings)]
+#![feature(in_band_lifetimes)]
+
+struct Foo<T>(T);
+
+impl Foo<&'s u8> {
+    fn bar<'s>(&self, x: &'s u8) {}
+    fn baz(x: for<'s> fn(&'s u32)) {}
+}
+
+fn main() {}

src/test/ui/in-band-lifetimes/shadow.stderr

@@ -0,0 +1,19 @@
+error[E0496]: lifetime name `'s` shadows a lifetime name that is already in scope
+  --> $DIR/shadow.rs:17:12
+   |
+16 | impl Foo<&'s u8> {
+   |           -- first declared here
+17 |     fn bar<'s>(&self, x: &'s u8) {}
+   |            ^^ lifetime 's already in scope
+
+error[E0496]: lifetime name `'s` shadows a lifetime name that is already in scope
+  --> $DIR/shadow.rs:18:19
+   |
+16 | impl Foo<&'s u8> {
+   |           -- first declared here
+17 |     fn bar<'s>(&self, x: &'s u8) {}
+18 |     fn baz(x: for<'s> fn(&'s u32)) {}
+   |                   ^^ lifetime 's already in scope
+
+error: aborting due to 2 previous errors
+