1 files changed, 67 insertions, 23 deletions

diff --git a/crates/ra_hir/src/ty/method_resolution.rs b/crates/ra_hir/src/ty/method_resolution.rs
index eb69344f6..ee0c7b00f 100644
--- a/crates/ra_hir/src/ty/method_resolution.rs
+++ b/crates/ra_hir/src/ty/method_resolution.rs
@@ -166,7 +166,19 @@ pub(crate) fn lookup_method(
     name: &Name,
     resolver: &Resolver,
 ) -> Option<(Ty, Function)> {
-    iterate_method_candidates(ty, db, resolver, Some(name), |ty, f| Some((ty.clone(), f)))
+    iterate_method_candidates(ty, db, resolver, Some(name), LookupMode::MethodCall, |ty, f| {
+        if let AssocItem::Function(f) = f {
+            Some((ty.clone(), f))
+        } else {
+            None
+        }
+    })
+}
+
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub(crate) enum LookupMode {
+    MethodCall,
+    Path,
 }
 
 // This would be nicer if it just returned an iterator, but that runs into
@@ -176,7 +188,8 @@ pub(crate) fn iterate_method_candidates<T>(
     db: &impl HirDatabase,
     resolver: &Resolver,
     name: Option<&Name>,
-    mut callback: impl FnMut(&Ty, Function) -> Option<T>,
+    mode: LookupMode,
+    mut callback: impl FnMut(&Ty, AssocItem) -> Option<T>,
 ) -> Option<T> {
     // For method calls, rust first does any number of autoderef, and then one
     // autoref (i.e. when the method takes &self or &mut self). We just ignore
@@ -188,13 +201,15 @@ pub(crate) fn iterate_method_candidates<T>(
     // rustc does an autoderef and then autoref again).
 
     let krate = resolver.krate()?;
+    // TODO no autoderef in LookupMode::Path
     for derefed_ty in autoderef::autoderef(db, resolver, ty.clone()) {
-        if let Some(result) = iterate_inherent_methods(&derefed_ty, db, name, krate, &mut callback)
+        if let Some(result) =
+            iterate_inherent_methods(&derefed_ty, db, name, mode, krate, &mut callback)
         {
             return Some(result);
         }
         if let Some(result) =
-            iterate_trait_method_candidates(&derefed_ty, db, resolver, name, &mut callback)
+            iterate_trait_method_candidates(&derefed_ty, db, resolver, name, mode, &mut callback)
         {
             return Some(result);
         }
@@ -207,7 +222,8 @@ fn iterate_trait_method_candidates<T>(
     db: &impl HirDatabase,
     resolver: &Resolver,
     name: Option<&Name>,
-    mut callback: impl FnMut(&Ty, Function) -> Option<T>,
+    mode: LookupMode,
+    mut callback: impl FnMut(&Ty, AssocItem) -> Option<T>,
 ) -> Option<T> {
     let krate = resolver.krate()?;
     // FIXME: maybe put the trait_env behind a query (need to figure out good input parameters for that)
@@ -231,21 +247,35 @@ fn iterate_trait_method_candidates<T>(
         // trait, but if we find out it doesn't, we'll skip the rest of the
         // iteration
         let mut known_implemented = inherently_implemented;
-        for item in data.items() {
-            if let AssocItem::Function(m) = *item {
-                let data = m.data(db);
-                if name.map_or(true, |name| data.name() == name) && data.has_self_param() {
-                    if !known_implemented {
-                        let goal = generic_implements_goal(db, env.clone(), t, ty.clone());
-                        if db.trait_solve(krate, goal).is_none() {
-                            continue 'traits;
-                        }
+        for &item in data.items() {
+            // TODO unify with the impl case
+            match item {
+                AssocItem::Function(m) => {
+                    let data = m.data(db);
+                    if !name.map_or(true, |name| data.name() == name)
+                        || (!data.has_self_param() && mode != LookupMode::Path)
+                    {
+                        continue;
                     }
-                    known_implemented = true;
-                    if let Some(result) = callback(&ty.value, m) {
-                        return Some(result);
+                }
+                AssocItem::Const(c) => {
+                    if !name.map_or(true, |name| Some(name) == c.name(db).as_ref())
+                        || (mode != LookupMode::Path)
+                    {
+                        continue;
                     }
                 }
+                _ => {}
+            };
+            if !known_implemented {
+                let goal = generic_implements_goal(db, env.clone(), t, ty.clone());
+                if db.trait_solve(krate, goal).is_none() {
+                    continue 'traits;
+                }
+            }
+            known_implemented = true;
+            if let Some(result) = callback(&ty.value, item) {
+                return Some(result);
             }
         }
     }
@@ -256,21 +286,35 @@ fn iterate_inherent_methods<T>(
     ty: &Canonical<Ty>,
     db: &impl HirDatabase,
     name: Option<&Name>,
+    mode: LookupMode,
     krate: Crate,
-    mut callback: impl FnMut(&Ty, Function) -> Option<T>,
+    mut callback: impl FnMut(&Ty, AssocItem) -> Option<T>,
 ) -> Option<T> {
     for krate in def_crates(db, krate, &ty.value)? {
         let impls = db.impls_in_crate(krate);
 
         for impl_block in impls.lookup_impl_blocks(&ty.value) {
             for item in impl_block.items(db) {
-                if let AssocItem::Function(f) = item {
-                    let data = f.data(db);
-                    if name.map_or(true, |name| data.name() == name) && data.has_self_param() {
-                        if let Some(result) = callback(&ty.value, f) {
-                            return Some(result);
+                match item {
+                    AssocItem::Function(f) => {
+                        let data = f.data(db);
+                        if !name.map_or(true, |name| data.name() == name)
+                            || (!data.has_self_param() && mode != LookupMode::Path)
+                        {
+                            continue;
                         }
                     }
+                    AssocItem::Const(c) => {
+                        if !name.map_or(true, |name| Some(name) == c.name(db).as_ref())
+                            || (mode != LookupMode::Path)
+                        {
+                            continue;
+                        }
+                    }
+                    _ => {}
+                }
+                if let Some(result) = callback(&ty.value, item) {
+                    return Some(result);
                 }
             }
         }