auto merge of #11156 : luqmana/rust/trait-object-coercion, r=pcwalton

This ports over @pcwalton's old pull that bitrotted (#5597). Fixes #10039.

r? @pcwalton / @nikomatsakis

5 files changed, 150 insertions, 2 deletions

diff --git a/src/test/compile-fail/map-types.rs b/src/test/compile-fail/map-types.rs
index c2c4a0b6908..0a1eab913be 100644
--- a/src/test/compile-fail/map-types.rs
+++ b/src/test/compile-fail/map-types.rs
@@ -17,7 +17,7 @@ use std::hashmap::HashMap;
 
 fn main() {
     let x: @HashMap<~str, ~str> = @HashMap::new();
-    let x: @Map<~str, ~str> = x as @Map<~str, ~str>;
+    let x: @Map<~str, ~str> = x;
     let y: @Map<uint, ~str> = @x;
-    //~^ ERROR expected trait std::container::Map but found @-ptr
+    //~^ ERROR failed to find an implementation of trait std::container::Map<uint,~str> for @std::container::Map<~str,~str>:'static
 }
diff --git a/src/test/compile-fail/trait-coercion-generic-bad.rs b/src/test/compile-fail/trait-coercion-generic-bad.rs
new file mode 100644
index 00000000000..2d73158add2
--- /dev/null
+++ b/src/test/compile-fail/trait-coercion-generic-bad.rs
@@ -0,0 +1,32 @@
+// Copyright 2012 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.
+
+#[feature(managed_boxes)];
+
+struct Struct {
+    person: &'static str
+}
+
+trait Trait<T> {
+    fn f(&self, x: T);
+}
+
+impl Trait<&'static str> for Struct {
+    fn f(&self, x: &'static str) {
+        println!("Hello, {}!", x);
+    }
+}
+
+fn main() {
+    let s: @Trait<int> = @Struct { person: "Fred" };    //~ ERROR expected Trait<int>, but found Trait<&'static str>
+    //~^ ERROR expected Trait<int>, but found Trait<&'static str>
+    s.f(1);
+}
+
diff --git a/src/test/compile-fail/trait-coercion-generic-regions.rs b/src/test/compile-fail/trait-coercion-generic-regions.rs
new file mode 100644
index 00000000000..1ea18a7c75b
--- /dev/null
+++ b/src/test/compile-fail/trait-coercion-generic-regions.rs
@@ -0,0 +1,32 @@
+// Copyright 2013 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.
+
+#[feature(managed_boxes)];
+
+struct Struct {
+    person: &'static str
+}
+
+trait Trait<T> {
+    fn f(&self, x: T);
+}
+
+impl Trait<&'static str> for Struct {
+    fn f(&self, x: &'static str) {
+        println!("Hello, {}!", x);
+    }
+}
+
+fn main() {
+    let person = ~"Fred";
+    let person: &str = person;  //~ ERROR borrowed value does not live long enough
+    let s: @Trait<&'static str> = @Struct { person: person };
+}
+
diff --git a/src/test/run-pass/trait-coercion-generic.rs b/src/test/run-pass/trait-coercion-generic.rs
new file mode 100644
index 00000000000..415f7baf3d9
--- /dev/null
+++ b/src/test/run-pass/trait-coercion-generic.rs
@@ -0,0 +1,42 @@
+// Copyright 2013 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.
+
+#[feature(managed_boxes)];
+
+trait Trait<T> {
+    fn f(&self, x: T);
+}
+
+struct Struct {
+    x: int,
+    y: int,
+}
+
+impl Trait<&'static str> for Struct {
+    fn f(&self, x: &'static str) {
+        println(~"Hi, " + x + ~"!");
+    }
+}
+
+fn f(x: @Trait<&'static str>) {
+    x.f("Sue");
+}
+
+pub fn main() {
+    let a = Struct { x: 1, y: 2 };
+    let b: @Trait<&'static str> = @a;
+    b.f("Fred");
+    let c: ~Trait<&'static str> = ~a;
+    c.f("Mary");
+    let d: &Trait<&'static str> = &a;
+    d.f("Joe");
+    f(@a);
+}
+
diff --git a/src/test/run-pass/trait-coercion.rs b/src/test/run-pass/trait-coercion.rs
new file mode 100644
index 00000000000..1c6968266e1
--- /dev/null
+++ b/src/test/run-pass/trait-coercion.rs
@@ -0,0 +1,42 @@
+// Copyright 2013 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.
+
+#[feature(managed_boxes)];
+
+trait Trait {
+    fn f(&self);
+}
+
+struct Struct {
+    x: int,
+    y: int,
+}
+
+impl Trait for Struct {
+    fn f(&self) {
+        println("Hi!");
+    }
+}
+
+fn f(x: @Trait) {
+    x.f();
+}
+
+pub fn main() {
+    let a = Struct { x: 1, y: 2 };
+    let b: @Trait = @a;
+    b.f();
+    let c: ~Trait = ~a;
+    c.f();
+    let d: &Trait = &a;
+    d.f();
+    f(@a);
+}
+