Rollup merge of rust-lang#56395 - Centril:stabilize-dbg-macro, r=SimonSapin

Stabilize dbg!(...)

Per FCP in rust-lang#54306 (which is ~1 day from completion).

r? @SimonSapin

The PR is fairly isolated so a rollup should probably work.

Author: Centril

src/libstd/macros.rs

@@ -224,11 +224,9 @@ macro_rules! eprintln {
 /// the value of a given expression. An example:
 ///
 /// ```rust
-/// #![feature(dbg_macro)]
-///
 /// let a = 2;
 /// let b = dbg!(a * 2) + 1;
-/// //      ^-- prints: [src/main.rs:4] a * 2 = 4
+/// //      ^-- prints: [src/main.rs:2] a * 2 = 4
 /// assert_eq!(b, 5);
 /// ```
 ///
@@ -262,8 +260,6 @@ macro_rules! eprintln {
 /// With a method call:
 ///
 /// ```rust
-/// #![feature(dbg_macro)]
-///
 /// fn foo(n: usize) {
 ///     if let Some(_) = dbg!(n.checked_sub(4)) {
 ///         // ...
@@ -282,8 +278,6 @@ macro_rules! eprintln {
 /// Naive factorial implementation:
 ///
 /// ```rust
-/// #![feature(dbg_macro)]
-///
 /// fn factorial(n: u32) -> u32 {
 ///     if dbg!(n <= 1) {
 ///         dbg!(1)
@@ -312,8 +306,6 @@ macro_rules! eprintln {
 /// The `dbg!(..)` macro moves the input:
 ///
 /// ```compile_fail
-/// #![feature(dbg_macro)]
-///
 /// /// A wrapper around `usize` which importantly is not Copyable.
 /// #[derive(Debug)]
 /// struct NoCopy(usize);
@@ -325,7 +317,7 @@ macro_rules! eprintln {
 ///
 /// [stderr]: https://en.wikipedia.org/wiki/Standard_streams#Standard_error_(stderr)
 #[macro_export]
-#[unstable(feature = "dbg_macro", issue = "54306")]
+#[stable(feature = "dbg_macro", since = "1.32.0")]
 macro_rules! dbg {
     ($val:expr) => {
         // Use of `match` here is intentional because it affects the lifetimes

src/test/ui/rfc-2361-dbg-macro/dbg-macro-expected-behavior.rs

@@ -5,8 +5,6 @@
 // Tests ensuring that `dbg!(expr)` has the expected run-time behavior.
 // as well as some compile time properties we expect.
 
-#![feature(dbg_macro)]
-
 #[derive(Copy, Clone, Debug)]
 struct Unit;
 
@@ -57,31 +55,31 @@ fn test() {
 
 fn validate_stderr(stderr: Vec<String>) {
     assert_eq!(stderr, &[
-        ":23] Unit = Unit",
+        ":21] Unit = Unit",
 
-        ":24] a = Unit",
+        ":22] a = Unit",
 
-        ":30] Point{x: 42, y: 24,} = Point {",
+        ":28] Point{x: 42, y: 24,} = Point {",
         "    x: 42,",
         "    y: 24",
         "}",
 
-        ":31] b = Point {",
+        ":29] b = Point {",
         "    x: 42,",
         "    y: 24",
         "}",
 
-        ":40] &a = NoCopy(",
+        ":38] &a = NoCopy(",
         "    1337",
         ")",
 
-        ":40] dbg!(& a) = NoCopy(",
+        ":38] dbg!(& a) = NoCopy(",
         "    1337",
         ")",
-        ":45] f(&42) = 42",
+        ":43] f(&42) = 42",
 
         "before",
-        ":50] { foo += 1; eprintln!(\"before\"); 7331 } = 7331",
+        ":48] { foo += 1; eprintln!(\"before\"); 7331 } = 7331",
     ]);
 }
 

src/test/ui/rfc-2361-dbg-macro/dbg-macro-feature-gate.rs

@@ -1,5 +1,5 @@
 error[E0382]: use of moved value: `a`
-  --> $DIR/dbg-macro-move-semantics.rs:11:18
+  --> $DIR/dbg-macro-move-semantics.rs:9:18
    |
 LL |     let _ = dbg!(a);
    |             ------- value moved here

src/test/ui/rfc-2361-dbg-macro/dbg-macro-feature-gate.stderr

@@ -1,7 +1,5 @@
 // Test ensuring that `dbg!(expr)` will take ownership of the argument.
 
-#![feature(dbg_macro)]
-
 #[derive(Debug)]
 struct NoCopy(usize);
 

src/test/ui/rfc-2361-dbg-macro/dbg-macro-move-semantics.nll.stderr

@@ -1,5 +1,5 @@
 error[E0382]: use of moved value: `a`
-  --> $DIR/dbg-macro-move-semantics.rs:11:18
+  --> $DIR/dbg-macro-move-semantics.rs:9:18
    |
 LL |     let _ = dbg!(a);
    |             ------- value moved here
@@ -10,7 +10,7 @@ LL |     let _ = dbg!(a);
    = note: this error originates in a macro outside of the current crate (in Nightly builds, run with -Z external-macro-backtrace for more info)
 
 error[E0382]: use of moved value: `a`
-  --> $DIR/dbg-macro-move-semantics.rs:11:13
+  --> $DIR/dbg-macro-move-semantics.rs:9:13
    |
 LL |     let _ = dbg!(a);
    |             ------- value moved here

src/test/ui/rfc-2361-dbg-macro/dbg-macro-move-semantics.rs

@@ -1,7 +1,5 @@
 // Test ensuring that `dbg!(expr)` requires the passed type to implement `Debug`.
 
-#![feature(dbg_macro)]
-
 struct NotDebug;
 
 fn main() {

src/test/ui/rfc-2361-dbg-macro/dbg-macro-move-semantics.stderr

@@ -1,5 +1,5 @@
 error[E0277]: `NotDebug` doesn't implement `std::fmt::Debug`
-  --> $DIR/dbg-macro-requires-debug.rs:8:23
+  --> $DIR/dbg-macro-requires-debug.rs:6:23
    |
 LL |     let _: NotDebug = dbg!(NotDebug);
    |                       ^^^^^^^^^^^^^^ `NotDebug` cannot be formatted using `{:?}`