Fix various names, e.g. Iterator not resolving in core prelude

Basically, `Iterator` is re-exported via several steps, which happened to not be
resolved yet when we got to the prelude import, but since the name resolved to
the reexport from `core::iter` (just to no actual items), we gave up trying to
resolve it further.

Maybe part of the problem is that we can have
`PartialResolvedImport::Unresolved` or `PartialResolvedImport::Indeterminate`
with `None` in all namespaces, and handle them differently.

Fixes #2683.

1 files changed, 1 insertions, 1 deletions

diff --git a/crates/ra_hir_def/src/nameres/collector.rs b/crates/ra_hir_def/src/nameres/collector.rs
index 35b852ee2..7499dff31 100644
--- a/crates/ra_hir_def/src/nameres/collector.rs
+++ b/crates/ra_hir_def/src/nameres/collector.rs
@@ -328,7 +328,7 @@ where
             );
 
             let def = res.resolved_def;
-            if res.reached_fixedpoint == ReachedFixedPoint::No {
+            if res.reached_fixedpoint == ReachedFixedPoint::No || def.is_none() {
                 return PartialResolvedImport::Unresolved;
             }