Handle more cases in cfg_accessible

compiler/rustc_resolve/src/macros.rs

@@ -443,11 +443,22 @@ impl<'a> ResolverExpand for Resolver<'a> {
                 PathResult::NonModule(partial_res) if partial_res.unresolved_segments() == 0 => {
                     return Ok(true);
                 }
+                PathResult::NonModule(..) |
+                // HACK(Urgau): This shouldn't be necessary
+                PathResult::Failed { is_error_from_last_segment: false, .. } => {
+                    self.session
+                        .struct_span_err(span, "not sure whether the path is accessible or not")
+                        .note("the type may have associated items, but we are currently not checking them")
+                        .emit();
+
+                    // If we get a partially resolved NonModule in one namespace, we should get the
+                    // same result in any other namespaces, so we can return early.
+                    return Ok(false);
+                }
                 PathResult::Indeterminate => indeterminate = true,
-                // FIXME: `resolve_path` is not ready to report partially resolved paths
-                // correctly, so we just report an error if the path was reported as unresolved.
-                // This needs to be fixed for `cfg_accessible` to be useful.
-                PathResult::NonModule(..) | PathResult::Failed { .. } => {}
+                // We can only be sure that a path doesn't exist after having tested all the
+                // posibilities, only at that time we can return false.
+                PathResult::Failed { .. } => {}
                 PathResult::Module(_) => panic!("unexpected path resolution"),
             }
         }
@@ -456,10 +467,6 @@ impl<'a> ResolverExpand for Resolver<'a> {
             return Err(Indeterminate);
         }
 
-        self.session
-            .struct_span_err(span, "not sure whether the path is accessible or not")
-            .span_note(span, "`cfg_accessible` is not fully implemented")
-            .emit();
         Ok(false)
     }
 

src/test/ui/conditional-compilation/cfg_accessible-bugs.rs

@@ -0,0 +1,18 @@
+// This test is a collection of test that should pass.
+//
+// check-fail
+
+#![feature(cfg_accessible)]
+#![feature(trait_alias)]
+
+trait TraitAlias = std::fmt::Debug + Send;
+
+// FIXME: Currently shows "cannot determine" but should be `false`
+#[cfg_accessible(unresolved)] //~ ERROR cannot determine
+const C: bool = true;
+
+// FIXME: Currently shows "not sure" but should be `false`
+#[cfg_accessible(TraitAlias::unresolved)] //~ ERROR not sure whether the path is accessible or not
+const D: bool = true;
+
+fn main() {}

src/test/ui/conditional-compilation/cfg_accessible-bugs.stderr

@@ -0,0 +1,16 @@
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-bugs.rs:15:18
+   |
+LL | #[cfg_accessible(TraitAlias::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: cannot determine whether the path is accessible or not
+  --> $DIR/cfg_accessible-bugs.rs:11:1
+   |
+LL | #[cfg_accessible(unresolved)]
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+error: aborting due to 2 previous errors
+

src/test/ui/conditional-compilation/cfg_accessible-not_sure.edition2015.stderr

@@ -0,0 +1,122 @@
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:14:18
+   |
+LL | #[cfg_accessible(Struct::existing)]
+   |                  ^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:16:18
+   |
+LL | #[cfg_accessible(Struct::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:25:18
+   |
+LL | #[cfg_accessible(Union::existing)]
+   |                  ^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:27:18
+   |
+LL | #[cfg_accessible(Union::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:36:18
+   |
+LL | #[cfg_accessible(Enum::Existing::existing)]
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:38:18
+   |
+LL | #[cfg_accessible(Enum::Existing::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:40:18
+   |
+LL | #[cfg_accessible(Enum::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:50:18
+   |
+LL | #[cfg_accessible(Trait::existing)]
+   |                  ^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:52:18
+   |
+LL | #[cfg_accessible(Trait::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:59:18
+   |
+LL | #[cfg_accessible(TypeAlias::existing)]
+   |                  ^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:61:18
+   |
+LL | #[cfg_accessible(TypeAlias::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:70:18
+   |
+LL | #[cfg_accessible(ForeignType::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:79:18
+   |
+LL | #[cfg_accessible(AssocType::AssocType::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:84:18
+   |
+LL | #[cfg_accessible(u8::unresolved)]
+   |                  ^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:86:18
+   |
+LL | #[cfg_accessible(u8::is_ascii)]
+   |                  ^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: aborting due to 15 previous errors
+

src/test/ui/conditional-compilation/cfg_accessible-not_sure.edition2021.stderr

@@ -0,0 +1,122 @@
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:14:18
+   |
+LL | #[cfg_accessible(Struct::existing)]
+   |                  ^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:16:18
+   |
+LL | #[cfg_accessible(Struct::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:25:18
+   |
+LL | #[cfg_accessible(Union::existing)]
+   |                  ^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:27:18
+   |
+LL | #[cfg_accessible(Union::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:36:18
+   |
+LL | #[cfg_accessible(Enum::Existing::existing)]
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:38:18
+   |
+LL | #[cfg_accessible(Enum::Existing::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:40:18
+   |
+LL | #[cfg_accessible(Enum::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:50:18
+   |
+LL | #[cfg_accessible(Trait::existing)]
+   |                  ^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:52:18
+   |
+LL | #[cfg_accessible(Trait::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:59:18
+   |
+LL | #[cfg_accessible(TypeAlias::existing)]
+   |                  ^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:61:18
+   |
+LL | #[cfg_accessible(TypeAlias::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:70:18
+   |
+LL | #[cfg_accessible(ForeignType::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:79:18
+   |
+LL | #[cfg_accessible(AssocType::AssocType::unresolved)]
+   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:84:18
+   |
+LL | #[cfg_accessible(u8::unresolved)]
+   |                  ^^^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: not sure whether the path is accessible or not
+  --> $DIR/cfg_accessible-not_sure.rs:86:18
+   |
+LL | #[cfg_accessible(u8::is_ascii)]
+   |                  ^^^^^^^^^^^^
+   |
+   = note: the type may have associated items, but we are currently not checking them
+
+error: aborting due to 15 previous errors
+