Rollup merge of #30610 - steveklabnik:gh30600, r=sfackler

Also, make its panic description identical in wording to assert_eq.

Fixes #30600

Author: steveklabnik

src/libcore/macros.rs

@@ -135,10 +135,10 @@ macro_rules! debug_assert {
     ($($arg:tt)*) => (if cfg!(debug_assertions) { assert!($($arg)*); })
 }
 
-/// Asserts that two expressions are equal to each other, testing equality in
-/// both directions.
+/// Asserts that two expressions are equal to each other.
 ///
-/// On panic, this macro will print the values of the expressions.
+/// On panic, this macro will print the values of the expressions with their
+/// debug representations.
 ///
 /// Unlike `assert_eq!`, `debug_assert_eq!` statements are only enabled in non
 /// optimized builds by default. An optimized build will omit all