type privacy: Check constructor types in tuple struct patterns

Author: petrochenkov

compiler/rustc_privacy/src/lib.rs

@@ -1302,6 +1302,27 @@ impl<'tcx> Visitor<'tcx> for TypePrivacyVisitor<'tcx> {
             return;
         }
 
+        match pattern.kind {
+            hir::PatKind::TupleStruct(qpath, ..) => {
+                // Tuple struct constructors have to be checked specially.
+                self.span = qpath.span();
+                let def_id = match qpath {
+                    hir::QPath::Resolved(_, path) => path.res.opt_def_id(),
+                    hir::QPath::TypeRelative(..) | hir::QPath::LangItem(..) => self
+                        .maybe_typeck_results
+                        .unwrap_or_else(|| span_bug!(self.span, "`hir::Pat` outside of a body"))
+                        .type_dependent_def_id(pattern.hir_id),
+                };
+
+                if let Some(def_id) = def_id {
+                    if self.visit(self.tcx.type_of(def_id).instantiate_identity()).is_break() {
+                        return;
+                    }
+                }
+            }
+            _ => {}
+        }
+
         intravisit::walk_pat(self, pattern);
     }
 

tests/ui/privacy/private-in-public-tuple-struct-pat.rs

@@ -0,0 +1,36 @@
+mod m {
+    struct Priv;
+
+    #[allow(private_interfaces)]
+    pub struct PubStruct(pub Priv);
+    pub enum PubEnum {
+        #[allow(private_interfaces)]
+        Variant(Priv),
+    }
+
+    impl PubStruct {
+        pub fn new() -> PubStruct {
+            PubStruct(Priv)
+        }
+    }
+    impl PubEnum {
+        pub fn new() -> PubEnum {
+            PubEnum::Variant(Priv)
+        }
+    }
+}
+
+fn main() {
+    match m::PubStruct::new() {
+        m::PubStruct(_) => {} //~ ERROR type `Priv` is private
+        m::PubStruct(..) => {} //~ ERROR type `Priv` is private
+    }
+
+    match m::PubEnum::new() {
+        m::PubEnum::Variant(_) => {} //~ ERROR type `Priv` is private
+        m::PubEnum::Variant(..) => {} //~ ERROR type `Priv` is private
+    }
+
+    let _ = m::PubStruct; //~ ERROR type `Priv` is private
+    let _ = m::PubEnum::Variant; //~ ERROR type `Priv` is private
+}

tests/ui/privacy/private-in-public-tuple-struct-pat.stderr

@@ -0,0 +1,38 @@
+error: type `Priv` is private
+  --> $DIR/private-in-public-tuple-struct-pat.rs:25:9
+   |
+LL |         m::PubStruct(_) => {}
+   |         ^^^^^^^^^^^^ private type
+
+error: type `Priv` is private
+  --> $DIR/private-in-public-tuple-struct-pat.rs:26:9
+   |
+LL |         m::PubStruct(..) => {}
+   |         ^^^^^^^^^^^^ private type
+
+error: type `Priv` is private
+  --> $DIR/private-in-public-tuple-struct-pat.rs:30:9
+   |
+LL |         m::PubEnum::Variant(_) => {}
+   |         ^^^^^^^^^^^^^^^^^^^ private type
+
+error: type `Priv` is private
+  --> $DIR/private-in-public-tuple-struct-pat.rs:31:9
+   |
+LL |         m::PubEnum::Variant(..) => {}
+   |         ^^^^^^^^^^^^^^^^^^^ private type
+
+error: type `Priv` is private
+  --> $DIR/private-in-public-tuple-struct-pat.rs:34:13
+   |
+LL |     let _ = m::PubStruct;
+   |             ^^^^^^^^^^^^ private type
+
+error: type `Priv` is private
+  --> $DIR/private-in-public-tuple-struct-pat.rs:35:13
+   |
+LL |     let _ = m::PubEnum::Variant;
+   |             ^^^^^^^^^^^^^^^^^^^ private type
+
+error: aborting due to 6 previous errors
+