Rollup merge of #63423 - estebank:priv-tuple, r=zackmdavis

Mention that tuple structs are private if any of their fields are

CC #39703

5 files changed, 144 insertions, 3 deletions

diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs
index e7feccf5069..ce2bc79ff60 100644
--- a/src/librustc_resolve/lib.rs
+++ b/src/librustc_resolve/lib.rs
@@ -50,7 +50,7 @@ use syntax::ast::{Item, ItemKind, ImplItem, ImplItemKind};
 use syntax::ast::{Label, Local, Mutability, Pat, PatKind, Path};
 use syntax::ast::{QSelf, TraitItem, TraitItemKind, TraitRef, Ty, TyKind};
 use syntax::ptr::P;
-use syntax::{span_err, struct_span_err, unwrap_or, walk_list};
+use syntax::{struct_span_err, unwrap_or, walk_list};
 
 use syntax_pos::{Span, DUMMY_SP, MultiSpan};
 use errors::{Applicability, DiagnosticBuilder, DiagnosticId};
@@ -4789,8 +4789,33 @@ impl<'a> Resolver<'a> {
         let mut reported_spans = FxHashSet::default();
         for &PrivacyError(dedup_span, ident, binding) in &self.privacy_errors {
             if reported_spans.insert(dedup_span) {
-                span_err!(self.session, ident.span, E0603, "{} `{}` is private",
-                          binding.descr(), ident.name);
+                let mut err = struct_span_err!(
+                    self.session,
+                    ident.span,
+                    E0603,
+                    "{} `{}` is private",
+                    binding.descr(),
+                    ident.name,
+                );
+                // FIXME: use the ctor's `def_id` to check wether any of the fields is not visible
+                match binding.kind {
+                    NameBindingKind::Res(Res::Def(DefKind::Ctor(
+                        CtorOf::Struct,
+                        CtorKind::Fn,
+                    ), _def_id), _) => {
+                        err.note("a tuple struct constructor is private if any of its fields \
+                                  is private");
+                    }
+                    NameBindingKind::Res(Res::Def(DefKind::Ctor(
+                        CtorOf::Variant,
+                        CtorKind::Fn,
+                    ), _def_id), _) => {
+                        err.note("a tuple variant constructor is private if any of its fields \
+                                  is private");
+                    }
+                    _ => {}
+                }
+                err.emit();
             }
         }
     }
diff --git a/src/test/ui/privacy/privacy5.stderr b/src/test/ui/privacy/privacy5.stderr
index 7568c346b24..532d1ac1e2f 100644
--- a/src/test/ui/privacy/privacy5.stderr
+++ b/src/test/ui/privacy/privacy5.stderr
@@ -3,288 +3,384 @@ error[E0603]: tuple struct `A` is private
    |
 LL |     let a = a::A(());
    |                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:52:16
    |
 LL |     let b = a::B(2);
    |                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:53:16
    |
 LL |     let c = a::C(2, 3);
    |                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `A` is private
   --> $DIR/privacy5.rs:56:12
    |
 LL |     let a::A(()) = a;
    |            ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `A` is private
   --> $DIR/privacy5.rs:57:12
    |
 LL |     let a::A(_) = a;
    |            ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `A` is private
   --> $DIR/privacy5.rs:58:18
    |
 LL |     match a { a::A(()) => {} }
    |                  ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `A` is private
   --> $DIR/privacy5.rs:59:18
    |
 LL |     match a { a::A(_) => {} }
    |                  ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:61:12
    |
 LL |     let a::B(_) = b;
    |            ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:62:12
    |
 LL |     let a::B(_b) = b;
    |            ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:63:18
    |
 LL |     match b { a::B(_) => {} }
    |                  ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:64:18
    |
 LL |     match b { a::B(_b) => {} }
    |                  ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:65:18
    |
 LL |     match b { a::B(1) => {} a::B(_) => {} }
    |                  ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:65:32
    |
 LL |     match b { a::B(1) => {} a::B(_) => {} }
    |                                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:68:12
    |
 LL |     let a::C(_, _) = c;
    |            ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:69:12
    |
 LL |     let a::C(_a, _) = c;
    |            ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:70:12
    |
 LL |     let a::C(_, _b) = c;
    |            ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:71:12
    |
 LL |     let a::C(_a, _b) = c;
    |            ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:72:18
    |
 LL |     match c { a::C(_, _) => {} }
    |                  ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:73:18
    |
 LL |     match c { a::C(_a, _) => {} }
    |                  ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:74:18
    |
 LL |     match c { a::C(_, _b) => {} }
    |                  ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:75:18
    |
 LL |     match c { a::C(_a, _b) => {} }
    |                  ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `A` is private
   --> $DIR/privacy5.rs:83:17
    |
 LL |     let a2 = a::A;
    |                 ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:84:17
    |
 LL |     let b2 = a::B;
    |                 ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:85:17
    |
 LL |     let c2 = a::C;
    |                 ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `A` is private
   --> $DIR/privacy5.rs:90:20
    |
 LL |     let a = other::A(());
    |                    ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:91:20
    |
 LL |     let b = other::B(2);
    |                    ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:92:20
    |
 LL |     let c = other::C(2, 3);
    |                    ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `A` is private
   --> $DIR/privacy5.rs:95:16
    |
 LL |     let other::A(()) = a;
    |                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `A` is private
   --> $DIR/privacy5.rs:96:16
    |
 LL |     let other::A(_) = a;
    |                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `A` is private
   --> $DIR/privacy5.rs:97:22
    |
 LL |     match a { other::A(()) => {} }
    |                      ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `A` is private
   --> $DIR/privacy5.rs:98:22
    |
 LL |     match a { other::A(_) => {} }
    |                      ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:100:16
    |
 LL |     let other::B(_) = b;
    |                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:101:16
    |
 LL |     let other::B(_b) = b;
    |                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:102:22
    |
 LL |     match b { other::B(_) => {} }
    |                      ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:103:22
    |
 LL |     match b { other::B(_b) => {} }
    |                      ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:104:22
    |
 LL |     match b { other::B(1) => {} other::B(_) => {} }
    |                      ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:104:40
    |
 LL |     match b { other::B(1) => {} other::B(_) => {} }
    |                                        ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:107:16
    |
 LL |     let other::C(_, _) = c;
    |                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:108:16
    |
 LL |     let other::C(_a, _) = c;
    |                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:109:16
    |
 LL |     let other::C(_, _b) = c;
    |                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:110:16
    |
 LL |     let other::C(_a, _b) = c;
    |                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:111:22
    |
 LL |     match c { other::C(_, _) => {} }
    |                      ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:112:22
    |
 LL |     match c { other::C(_a, _) => {} }
    |                      ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:113:22
    |
 LL |     match c { other::C(_, _b) => {} }
    |                      ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:114:22
    |
 LL |     match c { other::C(_a, _b) => {} }
    |                      ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `A` is private
   --> $DIR/privacy5.rs:122:21
    |
 LL |     let a2 = other::A;
    |                     ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `B` is private
   --> $DIR/privacy5.rs:123:21
    |
 LL |     let b2 = other::B;
    |                     ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `C` is private
   --> $DIR/privacy5.rs:124:21
    |
 LL |     let c2 = other::C;
    |                     ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error: aborting due to 48 previous errors
 
diff --git a/src/test/ui/resolve/privacy-struct-ctor.stderr b/src/test/ui/resolve/privacy-struct-ctor.stderr
index 9bf7d191174..72d62fe45ce 100644
--- a/src/test/ui/resolve/privacy-struct-ctor.stderr
+++ b/src/test/ui/resolve/privacy-struct-ctor.stderr
@@ -34,36 +34,48 @@ error[E0603]: tuple struct `Z` is private
    |
 LL |         n::Z;
    |            ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `S` is private
   --> $DIR/privacy-struct-ctor.rs:29:8
    |
 LL |     m::S;
    |        ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `S` is private
   --> $DIR/privacy-struct-ctor.rs:31:19
    |
 LL |     let _: S = m::S(2);
    |                   ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `Z` is private
   --> $DIR/privacy-struct-ctor.rs:35:11
    |
 LL |     m::n::Z;
    |           ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `S` is private
   --> $DIR/privacy-struct-ctor.rs:41:16
    |
 LL |     xcrate::m::S;
    |                ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: tuple struct `Z` is private
   --> $DIR/privacy-struct-ctor.rs:45:19
    |
 LL |     xcrate::m::n::Z;
    |                   ^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error: aborting due to 10 previous errors
 
diff --git a/src/test/ui/rfc-2008-non-exhaustive/struct.stderr b/src/test/ui/rfc-2008-non-exhaustive/struct.stderr
index 96040f11b52..d75a376286f 100644
--- a/src/test/ui/rfc-2008-non-exhaustive/struct.stderr
+++ b/src/test/ui/rfc-2008-non-exhaustive/struct.stderr
@@ -15,6 +15,8 @@ error[E0603]: tuple struct `TupleStruct` is private
    |
 LL |     let ts_explicit = structs::TupleStruct(640, 480);
    |                                ^^^^^^^^^^^
+   |
+   = note: a tuple struct constructor is private if any of its fields is private
 
 error[E0603]: unit struct `UnitStruct` is private
   --> $DIR/struct.rs:32:32
diff --git a/src/test/ui/rfc-2008-non-exhaustive/variant.stderr b/src/test/ui/rfc-2008-non-exhaustive/variant.stderr
index d9d6ea21b8b..ac0025ec758 100644
--- a/src/test/ui/rfc-2008-non-exhaustive/variant.stderr
+++ b/src/test/ui/rfc-2008-non-exhaustive/variant.stderr
@@ -3,6 +3,8 @@ error[E0603]: tuple variant `Tuple` is private
    |
 LL |     let variant_tuple = NonExhaustiveVariants::Tuple(640);
    |                                                ^^^^^
+   |
+   = note: a tuple variant constructor is private if any of its fields is private
 
 error[E0603]: unit variant `Unit` is private
   --> $DIR/variant.rs:14:47
@@ -21,12 +23,16 @@ error[E0603]: tuple variant `Tuple` is private
    |
 LL |         NonExhaustiveVariants::Tuple(fe_tpl) => "",
    |                                ^^^^^
+   |
+   = note: a tuple variant constructor is private if any of its fields is private
 
 error[E0603]: tuple variant `Tuple` is private
   --> $DIR/variant.rs:26:35
    |
 LL |     if let NonExhaustiveVariants::Tuple(fe_tpl) = variant_struct {
    |                                   ^^^^^
+   |
+   = note: a tuple variant constructor is private if any of its fields is private
 
 error[E0639]: cannot create non-exhaustive variant using struct expression
   --> $DIR/variant.rs:8:26