5 files changed, 46 insertions, 56 deletions

diff --git a/crates/ra_hir/src/lang_item.rs b/crates/ra_hir/src/lang_item.rs
index adcc682a2..a25d419e7 100644
--- a/crates/ra_hir/src/lang_item.rs
+++ b/crates/ra_hir/src/lang_item.rs
@@ -11,7 +11,7 @@ use crate::{
 pub enum LangItemTarget {
     Enum(Enum),
     Function(Function),
-    Impl(ImplBlock),
+    ImplBlock(ImplBlock),
     Static(Static),
     Struct(Struct),
     Trait(Trait),
@@ -22,7 +22,7 @@ impl LangItemTarget {
         match self {
             LangItemTarget::Enum(e) => e.module(db).krate(db),
             LangItemTarget::Function(f) => f.module(db).krate(db),
-            LangItemTarget::Impl(i) => i.module().krate(db),
+            LangItemTarget::ImplBlock(i) => i.module().krate(db),
             LangItemTarget::Static(s) => s.module(db).krate(db),
             LangItemTarget::Struct(s) => s.module(db).krate(db),
             LangItemTarget::Trait(t) => t.module(db).krate(db),
@@ -65,7 +65,7 @@ impl LangItems {
                 .nth(0);
             if let Some(lang_item_name) = lang_item_name {
                 let imp = ImplBlock::from_id(*module, impl_id);
-                self.items.entry(lang_item_name).or_insert(LangItemTarget::Impl(imp));
+                self.items.entry(lang_item_name).or_insert(LangItemTarget::ImplBlock(imp));
             }
         }
 
diff --git a/crates/ra_hir/src/resolve.rs b/crates/ra_hir/src/resolve.rs
index 61925e832..f2c85eb66 100644
--- a/crates/ra_hir/src/resolve.rs
+++ b/crates/ra_hir/src/resolve.rs
@@ -5,13 +5,15 @@ use rustc_hash::FxHashMap;
 
 use crate::{
     ModuleDef,
+    code_model_api::Crate,
     db::HirDatabase,
     name::{Name, KnownName},
     nameres::{PerNs, CrateDefMap, CrateModuleId},
     generics::GenericParams,
     expr::{scope::{ExprScopes, ScopeId}, PatId},
     impl_block::ImplBlock,
-    path::Path, Trait
+    path::Path,
+    Trait
 };
 
 #[derive(Debug, Clone, Default)]
@@ -190,13 +192,17 @@ impl Resolver {
             .flatten()
     }
 
-    pub(crate) fn module(&self) -> Option<(&CrateDefMap, CrateModuleId)> {
+    fn module(&self) -> Option<(&CrateDefMap, CrateModuleId)> {
         self.scopes.iter().rev().find_map(|scope| match scope {
             Scope::ModuleScope(m) => Some((&*m.crate_def_map, m.module_id)),
 
             _ => None,
         })
     }
+
+    pub(crate) fn krate(&self) -> Option<Crate> {
+        self.module().map(|t| t.0.krate())
+    }
 }
 
 impl Resolver {
diff --git a/crates/ra_hir/src/ty/infer.rs b/crates/ra_hir/src/ty/infer.rs
index 2275ac151..c7772a7f6 100644
--- a/crates/ra_hir/src/ty/infer.rs
+++ b/crates/ra_hir/src/ty/infer.rs
@@ -462,7 +462,7 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
         let remaining_index = remaining_index.unwrap_or(path.segments.len());
         let mut actual_def_ty: Option<Ty> = None;
 
-        let krate = resolver.module().map(|t| t.0.krate());
+        let krate = resolver.krate()?;
         // resolve intermediate segments
         for (i, segment) in path.segments[remaining_index..].iter().enumerate() {
             let ty = match resolved {
@@ -504,38 +504,36 @@ impl<'a, D: HirDatabase> InferenceContext<'a, D> {
 
             actual_def_ty = Some(ty.clone());
 
-            let item: crate::ModuleDef = krate.and_then(|k| {
-                ty.iterate_impl_items(self.db, k, |item| {
-                    let matching_def: Option<crate::ModuleDef> = match item {
-                        crate::ImplItem::Method(func) => {
-                            let sig = func.signature(self.db);
-                            if segment.name == *sig.name() {
-                                Some(func.into())
-                            } else {
-                                None
-                            }
+            let item: crate::ModuleDef = ty.iterate_impl_items(self.db, krate, |item| {
+                let matching_def: Option<crate::ModuleDef> = match item {
+                    crate::ImplItem::Method(func) => {
+                        let sig = func.signature(self.db);
+                        if segment.name == *sig.name() {
+                            Some(func.into())
+                        } else {
+                            None
                         }
+                    }
 
-                        crate::ImplItem::Const(konst) => {
-                            let sig = konst.signature(self.db);
-                            if segment.name == *sig.name() {
-                                Some(konst.into())
-                            } else {
-                                None
-                            }
+                    crate::ImplItem::Const(konst) => {
+                        let sig = konst.signature(self.db);
+                        if segment.name == *sig.name() {
+                            Some(konst.into())
+                        } else {
+                            None
                         }
+                    }
 
-                        // FIXME: Resolve associated types
-                        crate::ImplItem::TypeAlias(_) => None,
-                    };
-                    match matching_def {
-                        Some(_) => {
-                            self.write_assoc_resolution(id, item);
-                            return matching_def;
-                        }
-                        None => None,
+                    // FIXME: Resolve associated types
+                    crate::ImplItem::TypeAlias(_) => None,
+                };
+                match matching_def {
+                    Some(_) => {
+                        self.write_assoc_resolution(id, item);
+                        return matching_def;
                     }
-                })
+                    None => None,
+                }
             })?;
 
             resolved = Resolution::Def(item.into());
diff --git a/crates/ra_hir/src/ty/method_resolution.rs b/crates/ra_hir/src/ty/method_resolution.rs
index ba516313c..dca56a434 100644
--- a/crates/ra_hir/src/ty/method_resolution.rs
+++ b/crates/ra_hir/src/ty/method_resolution.rs
@@ -112,33 +112,19 @@ impl CrateImplBlocks {
     }
 }
 
-/// Rudimentary check whether an impl exists for a given type and trait; this
-/// will actually be done by chalk.
-pub(crate) fn implements(db: &impl HirDatabase, trait_ref: TraitRef) -> bool {
-    // FIXME use all trait impls in the whole crate graph
-    let krate = trait_ref.trait_.module(db).krate(db);
-    let krate = match krate {
-        Some(krate) => krate,
-        None => return false,
-    };
-    let crate_impl_blocks = db.impls_in_crate(krate);
-    let mut impl_blocks = crate_impl_blocks.lookup_impl_blocks_for_trait(&trait_ref.trait_);
-    impl_blocks.any(|impl_block| &impl_block.target_ty(db) == trait_ref.self_ty())
-}
-
-fn def_crate(db: &impl HirDatabase, cur_krate: Crate, ty: &Ty) -> Option<Crate> {
+fn def_crate(db: &impl HirDatabase, cur_crate: Crate, ty: &Ty) -> Option<Crate> {
     match ty {
         Ty::Apply(a_ty) => match a_ty.ctor {
             TypeCtor::Adt(def_id) => def_id.krate(db),
-            TypeCtor::Bool => lang_item_lookup(db, cur_krate, "bool")?.krate(db),
-            TypeCtor::Char => lang_item_lookup(db, cur_krate, "char")?.krate(db),
+            TypeCtor::Bool => lang_item_lookup(db, cur_crate, "bool")?.krate(db),
+            TypeCtor::Char => lang_item_lookup(db, cur_crate, "char")?.krate(db),
             TypeCtor::Float(UncertainFloatTy::Known(f)) => {
-                lang_item_lookup(db, cur_krate, f.ty_to_string())?.krate(db)
+                lang_item_lookup(db, cur_crate, f.ty_to_string())?.krate(db)
             }
             TypeCtor::Int(UncertainIntTy::Known(i)) => {
-                lang_item_lookup(db, cur_krate, i.ty_to_string())?.krate(db)
+                lang_item_lookup(db, cur_crate, i.ty_to_string())?.krate(db)
             }
-            TypeCtor::Str => lang_item_lookup(db, cur_krate, "str")?.krate(db),
+            TypeCtor::Str => lang_item_lookup(db, cur_crate, "str")?.krate(db),
             _ => None,
         },
         _ => None,
@@ -175,7 +161,7 @@ impl Ty {
         // find in the end takes &self, we still do the autoderef step (just as
         // rustc does an autoderef and then autoref again).
 
-        let krate = resolver.module().map(|t| t.0.krate())?;
+        let krate = resolver.krate()?;
         for derefed_ty in self.autoderef(db) {
             if let Some(result) =
                 derefed_ty.iterate_inherent_methods(db, name, krate, &mut callback)
diff --git a/crates/ra_ide_api/src/completion/complete_path.rs b/crates/ra_ide_api/src/completion/complete_path.rs
index c49147b9e..c41752ae7 100644
--- a/crates/ra_ide_api/src/completion/complete_path.rs
+++ b/crates/ra_ide_api/src/completion/complete_path.rs
@@ -39,7 +39,7 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
         hir::ModuleDef::Struct(s) => {
             let ty = s.ty(ctx.db);
             let krate = ctx.module.and_then(|m| m.krate(ctx.db));
-            krate.map_or((), |krate| {
+            if let Some(krate) = krate {
                 ty.iterate_impl_items(ctx.db, krate, |item| {
                     match item {
                         hir::ImplItem::Method(func) => {
@@ -53,7 +53,7 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
                     }
                     None::<()>
                 });
-            });
+            }
         }
         _ => return,
     };