assert_eq failure message easier to read

src/libcore/macros.rs

@@ -116,8 +116,9 @@ macro_rules! assert_eq {
         match (&$left, &$right) {
             (left_val, right_val) => {
                 if !(*left_val == *right_val) {
-                    panic!("assertion failed: `(left == right)` \
-                           (left: `{:?}`, right: `{:?}`)", left_val, right_val)
+                    panic!(r#"assertion failed: `(left == right)`
+  left: `{:?}`,
+ right: `{:?}`"#, left_val, right_val)
                 }
             }
         }
@@ -126,8 +127,9 @@ macro_rules! assert_eq {
         match (&($left), &($right)) {
             (left_val, right_val) => {
                 if !(*left_val == *right_val) {
-                    panic!("assertion failed: `(left == right)` \
-                           (left: `{:?}`, right: `{:?}`): {}", left_val, right_val,
+                    panic!(r#"assertion failed: `(left == right)`
+  left: `{:?}`,
+ right: `{:?}`: {}"#, left_val, right_val,
                            format_args!($($arg)+))
                 }
             }
@@ -162,8 +164,9 @@ macro_rules! assert_ne {
         match (&$left, &$right) {
             (left_val, right_val) => {
                 if *left_val == *right_val {
-                    panic!("assertion failed: `(left != right)` \
-                           (left: `{:?}`, right: `{:?}`)", left_val, right_val)
+                    panic!(r#"assertion failed: `(left != right)`
+  left: `{:?}`,
+ right: `{:?}`"#, left_val, right_val)
                 }
             }
         }
@@ -172,8 +175,9 @@ macro_rules! assert_ne {
         match (&($left), &($right)) {
             (left_val, right_val) => {
                 if *left_val == *right_val {
-                    panic!("assertion failed: `(left != right)` \
-                           (left: `{:?}`, right: `{:?}`): {}", left_val, right_val,
+                    panic!(r#"assertion failed: `(left != right)`
+  left: `{:?}`,
+ right: `{:?}`: {}"#, left_val, right_val,
                            format_args!($($arg)+))
                 }
             }

src/test/run-fail/assert-eq-macro-panic.rs

@@ -8,7 +8,9 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-// error-pattern:assertion failed: `(left == right)` (left: `14`, right: `15`)
+// error-pattern:assertion failed: `(left == right)`
+// error-pattern: left: `14`
+// error-pattern:right: `15`
 
 fn main() {
     assert_eq!(14, 15);

src/test/run-fail/assert-ne-macro-panic.rs

@@ -0,0 +1,17 @@
+// 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.
+
+// error-pattern:assertion failed: `(left != right)`
+// error-pattern: left: `14`
+// error-pattern:right: `14`
+
+fn main() {
+    assert_ne!(14, 14);
+}