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-rw-r--r--src/test/run-pass/object-safety-sized-self-generic-method.rs46
1 files changed, 46 insertions, 0 deletions
diff --git a/src/test/run-pass/object-safety-sized-self-generic-method.rs b/src/test/run-pass/object-safety-sized-self-generic-method.rs
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index 00000000000..1a42c4b6ef6
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+++ b/src/test/run-pass/object-safety-sized-self-generic-method.rs
@@ -0,0 +1,46 @@
+// Copyright 2014 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.
+
+// Check that a trait is still object-safe (and usable) if it has
+// generic methods so long as they require `Self : Sized`.
+
+trait Counter {
+    fn tick(&mut self) -> u32;
+    fn with<F:FnOnce(u32)>(&self, f: F) where Self : Sized;
+}
+
+struct CCounter {
+    c: u32
+}
+
+impl Counter for CCounter {
+    fn tick(&mut self) -> u32 { self.c += 1; self.c }
+    fn with<F:FnOnce(u32)>(&self, f: F) { f(self.c); }
+}
+
+fn tick1<C:Counter>(c: &mut C) {
+    tick2(c);
+    c.with(|i| ());
+}
+
+fn tick2(c: &mut Counter) {
+    tick3(c);
+}
+
+fn tick3<C:?Sized+Counter>(c: &mut C) {
+    c.tick();
+    c.tick();
+}
+
+fn main() {
+    let mut c = CCounter { c: 0 };
+    tick1(&mut c);
+    assert_eq!(c.tick(), 3);
+}