Rollup of 14 pull requests

src/libcore/iter/traits.rs

@@ -548,7 +548,7 @@ pub trait ExactSizeIterator: Iterator {
     /// assert_eq!(one_element.next(), None);
     /// ```
     #[inline]
-    #[unstable(feature = "exact_size_is_empty", issue = "0")]
+    #[unstable(feature = "exact_size_is_empty", issue = "35428")]
     fn is_empty(&self) -> bool {
         self.len() == 0
     }

src/librustc/traits/error_reporting.rs

@@ -870,10 +870,12 @@ impl<'a, 'gcx, 'tcx> InferCtxt<'a, 'gcx, 'tcx> {
 
 
     fn need_type_info(&self, span: Span, ty: Ty<'tcx>) {
-        span_err!(self.tcx.sess, span, E0282,
-                  "unable to infer enough type information about `{}`; \
-                   type annotations or generic parameter binding required",
-                  ty);
+        let mut err = struct_span_err!(self.tcx.sess, span, E0282,
+                                       "unable to infer enough type information about `{}`",
+                                       ty);
+        err.note("type annotations or generic parameter binding required");
+        err.span_label(span, &format!("cannot infer type for `{}`", ty));
+        err.emit()
     }
 
     fn note_obligation_cause<T>(&self,

src/librustc_resolve/lib.rs

@@ -3375,7 +3375,11 @@ impl<'a> Resolver<'a> {
             (true, _) | (_, true) => struct_span_err!(self.session, span, E0260, "{}", msg),
             _ => match (old_binding.is_import(), binding.is_import()) {
                 (false, false) => struct_span_err!(self.session, span, E0428, "{}", msg),
-                (true, true) => struct_span_err!(self.session, span, E0252, "{}", msg),
+                (true, true) => {
+                    let mut e = struct_span_err!(self.session, span, E0252, "{}", msg);
+                    e.span_label(span, &format!("already imported"));
+                    e
+                },
                 _ => {
                     let mut e = struct_span_err!(self.session, span, E0255, "{}", msg);
                     e.span_label(span, &format!("`{}` was already imported", name));

src/librustc_typeck/astconv.rs

@@ -1215,10 +1215,12 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
                                         type_str: &str,
                                         trait_str: &str,
                                         name: &str) {
-        span_err!(self.tcx().sess, span, E0223,
-                  "ambiguous associated type; specify the type using the syntax \
-                   `<{} as {}>::{}`",
-                  type_str, trait_str, name);
+        struct_span_err!(self.tcx().sess, span, E0223, "ambiguous associated type")
+            .span_label(span, &format!("ambiguous associated type"))
+            .note(&format!("specify the type using the syntax `<{} as {}>::{}`",
+                  type_str, trait_str, name))
+            .emit();
+
     }
 
     // Search for a bound on a type parameter which includes the associated item
@@ -2095,8 +2097,11 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
 
         if !trait_bounds.is_empty() {
             let b = &trait_bounds[0];
-            span_err!(self.tcx().sess, b.trait_ref.path.span, E0225,
-                      "only the builtin traits can be used as closure or object bounds");
+            let span = b.trait_ref.path.span;
+            struct_span_err!(self.tcx().sess, span, E0225,
+                             "only the builtin traits can be used as closure or object bounds")
+                .span_label(span, &format!("non-builtin trait used as bounds"))
+                .emit();
         }
 
         let region_bound =

src/librustc_typeck/check/_match.rs

@@ -93,13 +93,12 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                         end.span
                     };
 
-                    // Note: spacing here is intentional, we want a space before "start" and "end".
-                    span_err!(tcx.sess, span, E0029,
-                              "only char and numeric types are allowed in range patterns\n \
-                               start type: {}\n end type: {}",
-                              self.ty_to_string(lhs_ty),
-                              self.ty_to_string(rhs_ty)
-                    );
+                    struct_span_err!(tcx.sess, span, E0029,
+                        "only char and numeric types are allowed in range patterns")
+                        .span_label(span, &format!("ranges require char or numeric types"))
+                        .note(&format!("start type: {}", self.ty_to_string(lhs_ty)))
+                        .note(&format!("end type: {}", self.ty_to_string(rhs_ty)))
+                        .emit();
                     return;
                 }
 
@@ -700,9 +699,11 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
             for field in variant.fields
                 .iter()
                 .filter(|field| !used_fields.contains_key(&field.name)) {
-                span_err!(tcx.sess, span, E0027,
-                    "pattern does not mention field `{}`",
-                    field.name);
+                struct_span_err!(tcx.sess, span, E0027,
+                                "pattern does not mention field `{}`",
+                                field.name)
+                                .span_label(span, &format!("missing field `{}`", field.name))
+                                .emit();
             }
         }
     }

src/librustc_typeck/check/callee.rs

@@ -28,7 +28,9 @@ use rustc::hir;
 /// method that is called)
 pub fn check_legal_trait_for_method_call(ccx: &CrateCtxt, span: Span, trait_id: DefId) {
     if ccx.tcx.lang_items.drop_trait() == Some(trait_id) {
-        span_err!(ccx.tcx.sess, span, E0040, "explicit use of destructor method");
+        struct_span_err!(ccx.tcx.sess, span, E0040, "explicit use of destructor method")
+            .span_label(span, &format!("call to destructor method"))
+            .emit();
     }
 }
 

src/librustc_typeck/check/mod.rs

@@ -1136,11 +1136,16 @@ fn check_impl_items_against_trait<'a, 'tcx>(ccx: &CrateCtxt<'a, 'tcx>,
     }
 
     if !missing_items.is_empty() {
-        span_err!(tcx.sess, impl_span, E0046,
+        struct_span_err!(tcx.sess, impl_span, E0046,
             "not all trait items implemented, missing: `{}`",
             missing_items.iter()
                   .map(|name| name.to_string())
                   .collect::<Vec<_>>().join("`, `"))
+            .span_label(impl_span, &format!("missing `{}` in implementation",
+                missing_items.iter()
+                    .map(|name| name.to_string())
+                    .collect::<Vec<_>>().join("`, `"))
+            ).emit();
     }
 
     if !invalidated_items.is_empty() {

src/librustc_typeck/coherence/mod.rs

@@ -325,10 +325,17 @@ impl<'a, 'gcx, 'tcx> CoherenceChecker<'a, 'gcx, 'tcx> {
                                          name)
                 }
                 Err(CopyImplementationError::NotAnAdt) => {
-                       span_err!(tcx.sess, span, E0206,
-                                 "the trait `Copy` may not be implemented \
-                                  for this type; type is not a structure or \
-                                  enumeration")
+                    let item = tcx.map.expect_item(impl_node_id);
+                    let span = if let ItemImpl(_, _, _, _, ref ty, _) = item.node {
+                        ty.span
+                    } else {
+                        span
+                    };
+
+                    struct_span_err!(tcx.sess, span, E0206,
+                                     "the trait `Copy` may not be implemented for this type")
+                        .span_label(span, &format!("type is not a structure or enumeration"))
+                        .emit();
                 }
                 Err(CopyImplementationError::HasDestructor) => {
                     span_err!(tcx.sess, span, E0184,

src/librustc_typeck/collect.rs

@@ -367,8 +367,13 @@ impl<'a, 'tcx> AstConv<'tcx, 'tcx> for ItemCtxt<'a, 'tcx> {
                 _substs: Option<&mut Substs<'tcx>>,
                 _space: Option<ParamSpace>,
                 span: Span) -> Ty<'tcx> {
-        span_err!(self.tcx().sess, span, E0121,
-                  "the type placeholder `_` is not allowed within types on item signatures");
+        struct_span_err!(
+            self.tcx().sess,
+            span,
+            E0121,
+            "the type placeholder `_` is not allowed within types on item signatures"
+        ).span_label(span, &format!("not allowed in type signatures"))
+        .emit();
         self.tcx().types.err
     }
 
@@ -770,9 +775,10 @@ fn convert_item(ccx: &CrateCtxt, it: &hir::Item) {
                         let mut err = struct_span_err!(tcx.sess, impl_item.span, E0201,
                                                        "duplicate definitions with name `{}`:",
                                                        impl_item.name);
-                        span_note!(&mut err, *entry.get(),
-                                   "previous definition of `{}` here",
-                                   impl_item.name);
+                        err.span_label(*entry.get(),
+                                   &format!("previous definition of `{}` here",
+                                        impl_item.name));
+                        err.span_label(impl_item.span, &format!("duplicate definition"));
                         err.emit();
                     }
                     Vacant(entry) => {

src/librustc_typeck/lib.rs

@@ -211,11 +211,15 @@ fn check_main_fn_ty(ccx: &CrateCtxt,
             match tcx.map.find(main_id) {
                 Some(hir_map::NodeItem(it)) => {
                     match it.node {
-                        hir::ItemFn(_, _, _, _, ref ps, _)
-                        if ps.is_parameterized() => {
-                            span_err!(ccx.tcx.sess, main_span, E0131,
-                                      "main function is not allowed to have type parameters");
-                            return;
+                        hir::ItemFn(_, _, _, _, ref generics, _) => {
+                            if let Some(gen_span) = generics.span() {
+                                struct_span_err!(ccx.tcx.sess, gen_span, E0131,
+                                         "main function is not allowed to have type parameters")
+                                    .span_label(gen_span,
+                                                &format!("main cannot have type parameters"))
+                                    .emit();
+                                return;
+                            }
                         }
                         _ => ()
                     }

src/libstd/ffi/c_str.rs

@@ -373,6 +373,15 @@ impl NulError {
 
     /// Consumes this error, returning the underlying vector of bytes which
     /// generated the error in the first place.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::ffi::CString;
+    ///
+    /// let nul_error = CString::new("foo\0bar").unwrap_err();
+    /// assert_eq!(nul_error.into_vec(), b"foo\0bar");
+    /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn into_vec(self) -> Vec<u8> { self.1 }
 }

src/test/compile-fail/E0027.rs

@@ -17,6 +17,8 @@ fn main() {
     let d = Dog { name: "Rusty".to_string(), age: 8 };
 
     match d {
-        Dog { age: x } => {} //~ ERROR E0027
+        Dog { age: x } => {}
+        //~^ ERROR pattern does not mention field `name`
+        //~| NOTE missing field `name`
     }
 }

src/test/compile-fail/E0029.rs

@@ -12,7 +12,11 @@ fn main() {
     let s = "hoho";
 
     match s {
-        "hello" ... "world" => {} //~ ERROR E0029
+        "hello" ... "world" => {}
+        //~^ ERROR only char and numeric types are allowed in range patterns
+        //~| NOTE ranges require char or numeric types
+        //~| NOTE start type: &'static str
+        //~| NOTE end type: &'static str
         _ => {}
     }
 }

src/test/compile-fail/E0040.rs

@@ -20,5 +20,7 @@ impl Drop for Foo {
 
 fn main() {
     let mut x = Foo { x: -7 };
-    x.drop(); //~ ERROR E0040
+    x.drop(); 
+    //~^ ERROR E0040
+    //~| NOTE call to destructor method
 }

src/test/compile-fail/E0046.rs

@@ -14,7 +14,9 @@ trait Foo {
 
 struct Bar;
 
-impl Foo for Bar {} //~ ERROR E0046
+impl Foo for Bar {} 
+//~^ ERROR E0046
+//~| NOTE missing `foo` in implementation
 
 fn main() {
 }

src/test/compile-fail/E0131.rs

@@ -8,5 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-fn main<T>() { //~ ERROR E0131
+fn main<T>() {
+    //~^ ERROR E0131
+    //~| NOTE main cannot have type parameters
 }

src/test/compile-fail/E0206.rs

@@ -10,13 +10,17 @@
 
 type Foo = i32;
 
-impl Copy for Foo { } //~ ERROR E0206
-                      //~^ ERROR E0117
+impl Copy for Foo { }
+//~^ ERROR the trait `Copy` may not be implemented for this type
+//~| NOTE type is not a structure or enumeration
+//~| ERROR E0117
 
 #[derive(Copy, Clone)]
 struct Bar;
 
-impl Copy for &'static Bar { } //~ ERROR E0206
+impl Copy for &'static Bar { }
+//~^ ERROR the trait `Copy` may not be implemented for this type
+//~| NOTE type is not a structure or enumeration
 
 fn main() {
 }

src/test/compile-fail/E0223.rs

@@ -11,5 +11,8 @@
 trait MyTrait { type X; }
 
 fn main() {
-    let foo: MyTrait::X; //~ ERROR E0223
+    let foo: MyTrait::X;
+    //~^ ERROR ambiguous associated type
+    //~| NOTE ambiguous associated type
+    //~| NOTE specify the type using the syntax `<Type as MyTrait>::X`
 }

src/test/compile-fail/E0225.rs

@@ -9,5 +9,7 @@
 // except according to those terms.
 
 fn main() {
-    let _: Box<std::io::Read + std::io::Write>; //~ ERROR E0225
+    let _: Box<std::io::Read + std::io::Write>;
+    //~^ ERROR only the builtin traits can be used as closure or object bounds [E0225]
+    //~| NOTE non-builtin trait used as bounds
 }

src/test/compile-fail/associated-types-in-ambiguous-context.rs

@@ -15,15 +15,21 @@ trait Get {
 
 fn get<T:Get,U:Get>(x: T, y: U) -> Get::Value {}
 //~^ ERROR ambiguous associated type
+//~| NOTE ambiguous associated type
+//~| NOTE specify the type using the syntax `<Type as Get>::Value`
 
 trait Grab {
     type Value;
     fn grab(&self) -> Grab::Value;
     //~^ ERROR ambiguous associated type
+    //~| NOTE ambiguous associated type
+    //~| NOTE specify the type using the syntax `<Type as Grab>::Value`
 }
 
 type X = std::ops::Deref::Target;
 //~^ ERROR ambiguous associated type
+//~| NOTE ambiguous associated type
+//~| NOTE specify the type using the syntax `<Type as std::ops::Deref>::Target`
 
 fn main() {
 }

src/test/compile-fail/coherence-impls-copy.rs

@@ -27,22 +27,27 @@ impl Clone for TestE { fn clone(&self) -> Self { *self } }
 impl Copy for MyType {}
 
 impl Copy for &'static mut MyType {}
-//~^ ERROR E0206
+//~^ ERROR the trait `Copy` may not be implemented for this type
+//~| NOTE type is not a structure or enumeration
 impl Clone for MyType { fn clone(&self) -> Self { *self } }
 
 impl Copy for (MyType, MyType) {}
-//~^ ERROR E0206
+//~^ ERROR the trait `Copy` may not be implemented for this type
+//~| NOTE type is not a structure or enumeration
 //~| ERROR E0117
 
 impl Copy for &'static NotSync {}
-//~^ ERROR E0206
+//~^ ERROR the trait `Copy` may not be implemented for this type
+//~| NOTE type is not a structure or enumeration
 
 impl Copy for [MyType] {}
-//~^ ERROR E0206
+//~^ ERROR the trait `Copy` may not be implemented for this type
+//~| NOTE type is not a structure or enumeration
 //~| ERROR E0117
 
 impl Copy for &'static [NotSync] {}
-//~^ ERROR E0206
+//~^ ERROR the trait `Copy` may not be implemented for this type
+//~| NOTE type is not a structure or enumeration
 //~| ERROR E0117
 
 fn main() {

src/test/compile-fail/double-import.rs

@@ -7,8 +7,6 @@
 // <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.
-#![feature(no_core)]
-#![no_core]
 
 // This tests that conflicting imports shows both `use` lines
 // when reporting the error.
@@ -23,5 +21,6 @@ mod sub2 {
 
 use sub1::foo; //~ NOTE previous import of `foo` here
 use sub2::foo; //~ ERROR a value named `foo` has already been imported in this module [E0252]
+               //~| NOTE already imported
 
 fn main() {}

src/test/compile-fail/impl-duplicate-methods.rs

@@ -12,7 +12,9 @@ struct Foo;
 
 impl Foo {
     fn orange(&self) {} //~ NOTE previous definition of `orange` here
-    fn orange(&self) {} //~ ERROR duplicate definitions with name `orange`
+    fn orange(&self) {}
+    //~^ ERROR duplicate definition
+    //~| NOTE duplicate definition
 }
 
 fn main() {}