Turn on box(PLACE) expr deprecation warning post-snapshot.

Author: eddyb

src/liballoc/boxed.rs

@@ -297,7 +297,7 @@ impl<T: Clone> Clone for Box<T> {
     /// let y = x.clone();
     /// ```
     #[inline]
-    fn clone(&self) -> Box<T> { box (HEAP) {(**self).clone()} }
+    fn clone(&self) -> Box<T> { box {(**self).clone()} }
     /// Copies `source`'s contents into `self` without creating a new allocation.
     ///
     /// # Examples

src/libsyntax/parse/parser.rs

@@ -2637,19 +2637,15 @@ impl<'a> Parser<'a> {
             //
             // ... but for now: check for a place: `box(PLACE) EXPR`.
 
-            if try!(self.eat(&token::OpenDelim(token::Paren)) ){
-                // SNAP d4432b3
-                // Enable this warning after snapshot ...
-                //
-                // let box_span = mk_sp(lo, self.last_span.hi);
-                // self.span_warn(
-                //     box_span,
-                //     "deprecated syntax; use the `in` keyword now \
-                //            (e.g. change `box (<expr>) <expr>` to \
-                //                         `in <expr> { <expr> }`)");
+            if try!(self.eat(&token::OpenDelim(token::Paren))) {
+                let box_span = mk_sp(lo, self.last_span.hi);
+                self.span_warn(box_span,
+                    "deprecated syntax; use the `in` keyword now \
+                           (e.g. change `box (<expr>) <expr>` to \
+                                        `in <expr> { <expr> }`)");
 
                 // Continue supporting `box () EXPR` (temporarily)
-                if !try!(self.eat(&token::CloseDelim(token::Paren)) ){
+                if !try!(self.eat(&token::CloseDelim(token::Paren))) {
                     let place = try!(self.parse_expr_nopanic());
                     try!(self.expect(&token::CloseDelim(token::Paren)));
                     // Give a suggestion to use `box()` when a parenthesised expression is used

src/test/compile-fail/borrowck-lend-flow-if.rs

@@ -24,6 +24,7 @@ fn produce<T>() -> T { panic!(); }
 
 fn inc(v: &mut Box<isize>) {
     *v = box() (**v + 1);
+    //~^ WARN deprecated syntax
 }
 
 fn pre_freeze_cond() {

src/test/compile-fail/borrowck-lend-flow-loop.rs

@@ -23,6 +23,7 @@ fn produce<T>() -> T { panic!(); }
 
 fn inc(v: &mut Box<isize>) {
     *v = box() (**v + 1);
+    //~^ WARN deprecated syntax
 }
 
 fn loop_overarching_alias_mut() {

src/test/compile-fail/borrowck-lend-flow.rs

@@ -24,6 +24,7 @@ fn produce<T>() -> T { panic!(); }
 
 fn inc(v: &mut Box<isize>) {
     *v = box() (**v + 1);
+    //~^ WARN deprecated syntax
 }
 
 fn pre_freeze() {

src/test/compile-fail/borrowck-loan-in-overloaded-op.rs

@@ -23,6 +23,7 @@ impl Add for foo {
         let foo(box i) = self;
         let foo(box j) = f;
         foo(box() (i + j))
+        //~^ WARN deprecated syntax
     }
 }
 

src/test/compile-fail/feature-gate-box-expr.rs

@@ -21,5 +21,6 @@ fn main() {
     println!("x: {}", x);
 
     let x = box () 'c'; //~ ERROR box expression syntax is experimental
+    //~^ WARN deprecated syntax
     println!("x: {}", x);
 }

src/test/compile-fail/feature-gate-placement-expr.rs

@@ -20,6 +20,7 @@ fn main() {
     use std::boxed::HEAP;
 
     let x = box (HEAP) 'c'; //~ ERROR placement-in expression syntax is experimental
+    //~^ WARN deprecated syntax
     println!("x: {}", x);
 
     let x = in HEAP { 'c' }; //~ ERROR placement-in expression syntax is experimental

src/test/compile-fail/issue-14084.rs

@@ -15,4 +15,5 @@ fn main() {
     box ( () ) 0;
     //~^ ERROR: the trait `core::ops::Placer<_>` is not implemented
     //~| ERROR: the trait `core::ops::Placer<_>` is not implemented
+    //~| WARN deprecated syntax
 }

src/test/compile-fail/moves-based-on-type-tuple.rs

@@ -10,7 +10,10 @@
 
 #![feature(box_syntax)]
 
-fn dup(x: Box<isize>) -> Box<(Box<isize>,Box<isize>)> { box() (x, x) } //~ ERROR use of moved value
+fn dup(x: Box<isize>) -> Box<(Box<isize>,Box<isize>)> {
+    box() (x, x) //~ ERROR use of moved value
+    //~^ WARN deprecated syntax
+}
 fn main() {
     dup(box 3);
 }

src/test/parse-fail/parenthesized-box-expr-message.rs

@@ -14,5 +14,6 @@ fn main() {
     box (1 + 1)
     //~^ HELP try using `box ()` instead:
     //~| SUGGESTION box () (1 + 1)
+    //~| WARN deprecated syntax
     ; //~ ERROR expected expression, found `;`
 }