resolve: Point at the private item definitions in privacy errors

Author: petrochenkov

src/librustc_resolve/diagnostics.rs

@@ -917,15 +917,21 @@ impl<'a> Resolver<'a> {
         let PrivacyError { ident, binding, .. } = *privacy_error;
         let session = &self.session;
         let mk_struct_span_error = |is_constructor| {
-            struct_span_err!(
-                session,
-                ident.span,
-                E0603,
-                "{}{} `{}` is private",
-                binding.res().descr(),
-                if is_constructor { " constructor" } else { "" },
-                ident.name,
-            )
+            let mut descr = binding.res().descr().to_string();
+            if is_constructor {
+                descr += " constructor";
+            }
+
+            let mut err =
+                struct_span_err!(session, ident.span, E0603, "{} `{}` is private", descr, ident);
+
+            err.span_label(ident.span, &format!("this {} is private", descr));
+            err.span_note(
+                session.source_map().def_span(binding.span),
+                &format!("the {} `{}` is defined here", descr, ident),
+            );
+
+            err
         };
 
         let mut err = if let NameBindingKind::Res(

src/test/ui/error-codes/E0603.stderr

@@ -2,7 +2,13 @@ error[E0603]: constant `PRIVATE` is private
   --> $DIR/E0603.rs:6:17
    |
 LL |     SomeModule::PRIVATE;
-   |                 ^^^^^^^
+   |                 ^^^^^^^ this constant is private
+   |
+note: the constant `PRIVATE` is defined here
+  --> $DIR/E0603.rs:2:5
+   |
+LL |     const PRIVATE: u32 = 0x_a_bad_1dea_u32;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 error: aborting due to previous error
 

src/test/ui/error-festival.stderr

@@ -8,7 +8,13 @@ error[E0603]: constant `FOO` is private
   --> $DIR/error-festival.rs:22:10
    |
 LL |     foo::FOO;
-   |          ^^^
+   |          ^^^ this constant is private
+   |
+note: the constant `FOO` is defined here
+  --> $DIR/error-festival.rs:7:5
+   |
+LL |     const FOO: u32 = 0;
+   |     ^^^^^^^^^^^^^^^^^^^
 
 error[E0368]: binary assignment operation `+=` cannot be applied to type `&str`
   --> $DIR/error-festival.rs:12:5

src/test/ui/export-import.stderr

@@ -2,7 +2,13 @@ error[E0603]: function `unexported` is private
   --> $DIR/export-import.rs:1:8
    |
 LL | use m::unexported;
-   |        ^^^^^^^^^^
+   |        ^^^^^^^^^^ this function is private
+   |
+note: the function `unexported` is defined here
+  --> $DIR/export-import.rs:7:5
+   |
+LL |     fn unexported() { }
+   |     ^^^^^^^^^^^^^^^
 
 error: aborting due to previous error
 

src/test/ui/export-tag-variant.stderr

@@ -2,7 +2,13 @@ error[E0603]: enum `Y` is private
   --> $DIR/export-tag-variant.rs:7:26
    |
 LL | fn main() { let z = foo::Y::Y1; }
-   |                          ^
+   |                          ^ this enum is private
+   |
+note: the enum `Y` is defined here
+  --> $DIR/export-tag-variant.rs:4:5
+   |
+LL |     enum Y { Y1 }
+   |     ^^^^^^
 
 error: aborting due to previous error
 

src/test/ui/export.stderr

@@ -26,7 +26,13 @@ error[E0603]: function `z` is private
   --> $DIR/export.rs:10:18
    |
 LL | fn main() { foo::z(10); }
-   |                  ^
+   |                  ^ this function is private
+   |
+note: the function `z` is defined here
+  --> $DIR/export.rs:5:5
+   |
+LL |     fn z(y: isize) { log(debug, y); }
+   |     ^^^^^^^^^^^^^^
 
 error: aborting due to 5 previous errors
 

src/test/ui/extern/extern-crate-visibility.stderr

@@ -2,13 +2,25 @@ error[E0603]: crate `core` is private
   --> $DIR/extern-crate-visibility.rs:6:10
    |
 LL | use foo::core::cell;
-   |          ^^^^
+   |          ^^^^ this crate is private
+   |
+note: the crate `core` is defined here
+  --> $DIR/extern-crate-visibility.rs:2:5
+   |
+LL |     extern crate core;
+   |     ^^^^^^^^^^^^^^^^^^
 
 error[E0603]: crate `core` is private
   --> $DIR/extern-crate-visibility.rs:9:10
    |
 LL |     foo::core::cell::Cell::new(0);
-   |          ^^^^
+   |          ^^^^ this crate is private
+   |
+note: the crate `core` is defined here
+  --> $DIR/extern-crate-visibility.rs:2:5
+   |
+LL |     extern crate core;
+   |     ^^^^^^^^^^^^^^^^^^
 
 error: aborting due to 2 previous errors
 

src/test/ui/hygiene/privacy.stderr

@@ -2,7 +2,13 @@ error[E0603]: function `f` is private
   --> $DIR/privacy.rs:16:14
    |
 LL |         foo::f()
-   |              ^
+   |              ^ this function is private
+   |
+note: the function `f` is defined here
+  --> $DIR/privacy.rs:4:5
+   |
+LL |     fn f() {}
+   |     ^^^^^^
 
 error: aborting due to previous error
 

src/test/ui/import.stderr

@@ -17,7 +17,13 @@ error[E0603]: unresolved item `foo` is private
   --> $DIR/import.rs:15:10
    |
 LL |     zed::foo();
-   |          ^^^
+   |          ^^^ this unresolved item is private
+   |
+note: the unresolved item `foo` is defined here
+  --> $DIR/import.rs:10:9
+   |
+LL |     use foo;
+   |         ^^^
 
 error: aborting due to 3 previous errors
 

src/test/ui/imports/issue-55884-2.stderr

@@ -2,7 +2,13 @@ error[E0603]: struct `ParseOptions` is private
   --> $DIR/issue-55884-2.rs:12:17
    |
 LL | pub use parser::ParseOptions;
-   |                 ^^^^^^^^^^^^
+   |                 ^^^^^^^^^^^^ this struct is private
+   |
+note: the struct `ParseOptions` is defined here
+  --> $DIR/issue-55884-2.rs:9:9
+   |
+LL |     use ParseOptions;
+   |         ^^^^^^^^^^^^
 
 error: aborting due to previous error