Merge #1154

1154: Initial support for lang items (and str completion) r=flodiebold a=marcogroppo

This PR adds partial support for lang items.
For now, the only supported lang items are the ones that target an impl block.

Lang items are now resolved during type inference - this means that `str` completion now works.

Fixes #1139.

(thanks Florian Diebold for the help!)


Co-authored-by: Marco Groppo <[email protected]>

1 files changed, 14 insertions, 11 deletions

diff --git a/crates/ra_ide_api/src/completion/complete_path.rs b/crates/ra_ide_api/src/completion/complete_path.rs
index bc03a7095..c41752ae7 100644
--- a/crates/ra_ide_api/src/completion/complete_path.rs
+++ b/crates/ra_ide_api/src/completion/complete_path.rs
@@ -38,19 +38,22 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
         }
         hir::ModuleDef::Struct(s) => {
             let ty = s.ty(ctx.db);
-            ty.iterate_impl_items(ctx.db, |item| {
-                match item {
-                    hir::ImplItem::Method(func) => {
-                        let sig = func.signature(ctx.db);
-                        if !sig.has_self_param() {
-                            acc.add_function(ctx, func);
+            let krate = ctx.module.and_then(|m| m.krate(ctx.db));
+            if let Some(krate) = krate {
+                ty.iterate_impl_items(ctx.db, krate, |item| {
+                    match item {
+                        hir::ImplItem::Method(func) => {
+                            let sig = func.signature(ctx.db);
+                            if !sig.has_self_param() {
+                                acc.add_function(ctx, func);
+                            }
                         }
+                        hir::ImplItem::Const(ct) => acc.add_const(ctx, ct),
+                        hir::ImplItem::TypeAlias(ty) => acc.add_type_alias(ctx, ty),
                     }
-                    hir::ImplItem::Const(ct) => acc.add_const(ctx, ct),
-                    hir::ImplItem::TypeAlias(ty) => acc.add_type_alias(ctx, ty),
-                }
-                None::<()>
-            });
+                    None::<()>
+                });
+            }
         }
         _ => return,
     };