5 files changed, 35 insertions, 50 deletions

diff --git a/crates/ra_ide_api/src/completion/complete_dot.rs b/crates/ra_ide_api/src/completion/complete_dot.rs
index 37985b398..473edc50e 100644
--- a/crates/ra_ide_api/src/completion/complete_dot.rs
+++ b/crates/ra_ide_api/src/completion/complete_dot.rs
@@ -1,41 +1,39 @@
 use hir::{Ty, Def};
 
-use crate::Cancelable;
 use crate::completion::{CompletionContext, Completions, CompletionKind, CompletionItem, CompletionItemKind};
 
 /// Complete dot accesses, i.e. fields or methods (currently only fields).
-pub(super) fn complete_dot(acc: &mut Completions, ctx: &CompletionContext) -> Cancelable<()> {
+pub(super) fn complete_dot(acc: &mut Completions, ctx: &CompletionContext) {
     let (function, receiver) = match (&ctx.function, ctx.dot_receiver) {
         (Some(function), Some(receiver)) => (function, receiver),
-        _ => return Ok(()),
+        _ => return,
     };
-    let infer_result = function.infer(ctx.db)?;
-    let syntax_mapping = function.body_syntax_mapping(ctx.db)?;
+    let infer_result = function.infer(ctx.db);
+    let syntax_mapping = function.body_syntax_mapping(ctx.db);
     let expr = match syntax_mapping.node_expr(receiver) {
         Some(expr) => expr,
-        None => return Ok(()),
+        None => return,
     };
     let receiver_ty = infer_result[expr].clone();
     if !ctx.is_call {
-        complete_fields(acc, ctx, receiver_ty.clone())?;
+        complete_fields(acc, ctx, receiver_ty.clone());
     }
-    complete_methods(acc, ctx, receiver_ty)?;
-    Ok(())
+    complete_methods(acc, ctx, receiver_ty);
 }
 
-fn complete_fields(acc: &mut Completions, ctx: &CompletionContext, receiver: Ty) -> Cancelable<()> {
+fn complete_fields(acc: &mut Completions, ctx: &CompletionContext, receiver: Ty) {
     for receiver in receiver.autoderef(ctx.db) {
         match receiver {
             Ty::Adt { def_id, .. } => {
-                match def_id.resolve(ctx.db)? {
+                match def_id.resolve(ctx.db) {
                     Def::Struct(s) => {
-                        for field in s.fields(ctx.db)? {
+                        for field in s.fields(ctx.db) {
                             CompletionItem::new(
                                 CompletionKind::Reference,
                                 field.name().to_string(),
                             )
                             .kind(CompletionItemKind::Field)
-                            .set_detail(field.ty(ctx.db)?.map(|ty| ty.to_string()))
+                            .set_detail(field.ty(ctx.db).map(|ty| ty.to_string()))
                             .add_to(acc);
                         }
                     }
@@ -53,14 +51,9 @@ fn complete_fields(acc: &mut Completions, ctx: &CompletionContext, receiver: Ty)
             _ => {}
         };
     }
-    Ok(())
 }
 
-fn complete_methods(
-    acc: &mut Completions,
-    ctx: &CompletionContext,
-    receiver: Ty,
-) -> Cancelable<()> {
+fn complete_methods(acc: &mut Completions, ctx: &CompletionContext, receiver: Ty) {
     receiver.iterate_methods(ctx.db, |func| {
         let sig = func.signature(ctx.db);
         if sig.has_self_param() {
@@ -69,9 +62,8 @@ fn complete_methods(
                 .kind(CompletionItemKind::Method)
                 .add_to(acc);
         }
-        Ok(None::<()>)
-    })?;
-    Ok(())
+        None::<()>
+    });
 }
 
 #[cfg(test)]
diff --git a/crates/ra_ide_api/src/completion/complete_path.rs b/crates/ra_ide_api/src/completion/complete_path.rs
index a25ad3f13..1eded7658 100644
--- a/crates/ra_ide_api/src/completion/complete_path.rs
+++ b/crates/ra_ide_api/src/completion/complete_path.rs
@@ -1,20 +1,19 @@
 use crate::{
-    Cancelable,
     completion::{CompletionItem, CompletionItemKind, Completions, CompletionKind, CompletionContext},
 };
 
-pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) -> Cancelable<()> {
+pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
     let (path, module) = match (&ctx.path_prefix, &ctx.module) {
         (Some(path), Some(module)) => (path.clone(), module),
-        _ => return Ok(()),
+        _ => return,
     };
-    let def_id = match module.resolve_path(ctx.db, &path)?.take_types() {
+    let def_id = match module.resolve_path(ctx.db, &path).take_types() {
         Some(it) => it,
-        None => return Ok(()),
+        None => return,
     };
-    match def_id.resolve(ctx.db)? {
+    match def_id.resolve(ctx.db) {
         hir::Def::Module(module) => {
-            let module_scope = module.scope(ctx.db)?;
+            let module_scope = module.scope(ctx.db);
             for (name, res) in module_scope.entries() {
                 CompletionItem::new(CompletionKind::Reference, name.to_string())
                     .from_resolution(ctx, res)
@@ -22,7 +21,7 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) -> C
             }
         }
         hir::Def::Enum(e) => {
-            e.variants(ctx.db)?
+            e.variants(ctx.db)
                 .into_iter()
                 .for_each(|(variant_name, _variant)| {
                     CompletionItem::new(CompletionKind::Reference, variant_name.to_string())
@@ -30,9 +29,8 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) -> C
                         .add_to(acc)
                 });
         }
-        _ => return Ok(()),
+        _ => return,
     };
-    Ok(())
 }
 
 #[cfg(test)]
diff --git a/crates/ra_ide_api/src/completion/complete_scope.rs b/crates/ra_ide_api/src/completion/complete_scope.rs
index 770a0fdf2..699680748 100644
--- a/crates/ra_ide_api/src/completion/complete_scope.rs
+++ b/crates/ra_ide_api/src/completion/complete_scope.rs
@@ -1,26 +1,23 @@
 use rustc_hash::FxHashSet;
 use ra_syntax::TextUnit;
 
-use crate::{
-    Cancelable,
-    completion::{CompletionItem, CompletionItemKind, Completions, CompletionKind, CompletionContext},
-};
+use crate::completion::{CompletionItem, CompletionItemKind, Completions, CompletionKind, CompletionContext};
 
-pub(super) fn complete_scope(acc: &mut Completions, ctx: &CompletionContext) -> Cancelable<()> {
+pub(super) fn complete_scope(acc: &mut Completions, ctx: &CompletionContext) {
     if !ctx.is_trivial_path {
-        return Ok(());
+        return;
     }
     let module = match &ctx.module {
         Some(it) => it,
-        None => return Ok(()),
+        None => return,
     };
     if let Some(function) = &ctx.function {
-        let scopes = function.scopes(ctx.db)?;
+        let scopes = function.scopes(ctx.db);
         complete_fn(acc, &scopes, ctx.offset);
     }
 
-    let module_scope = module.scope(ctx.db)?;
-    let (file_id, _) = module.definition_source(ctx.db)?;
+    let module_scope = module.scope(ctx.db);
+    let (file_id, _) = module.definition_source(ctx.db);
     module_scope
         .entries()
         .filter(|(_name, res)| {
@@ -40,7 +37,6 @@ pub(super) fn complete_scope(acc: &mut Completions, ctx: &CompletionContext) ->
                 .from_resolution(ctx, res)
                 .add_to(acc)
         });
-    Ok(())
 }
 
 fn complete_fn(acc: &mut Completions, scopes: &hir::ScopesWithSyntaxMapping, offset: TextUnit) {
diff --git a/crates/ra_ide_api/src/completion/completion_context.rs b/crates/ra_ide_api/src/completion/completion_context.rs
index 113f6c070..e537e0082 100644
--- a/crates/ra_ide_api/src/completion/completion_context.rs
+++ b/crates/ra_ide_api/src/completion/completion_context.rs
@@ -7,7 +7,7 @@ use ra_syntax::{
 };
 use hir::source_binder;
 
-use crate::{db, FilePosition, Cancelable};
+use crate::{db, FilePosition};
 
 /// `CompletionContext` is created early during completion to figure out, where
 /// exactly is the cursor, syntax-wise.
@@ -41,10 +41,9 @@ impl<'a> CompletionContext<'a> {
         db: &'a db::RootDatabase,
         original_file: &'a SourceFile,
         position: FilePosition,
-    ) -> Cancelable<Option<CompletionContext<'a>>> {
-        let module = source_binder::module_from_position(db, position)?;
-        let leaf =
-            ctry!(find_leaf_at_offset(original_file.syntax(), position.offset).left_biased());
+    ) -> Option<CompletionContext<'a>> {
+        let module = source_binder::module_from_position(db, position);
+        let leaf = find_leaf_at_offset(original_file.syntax(), position.offset).left_biased()?;
         let mut ctx = CompletionContext {
             db,
             leaf,
@@ -63,7 +62,7 @@ impl<'a> CompletionContext<'a> {
             is_call: false,
         };
         ctx.fill(original_file, position.offset);
-        Ok(Some(ctx))
+        Some(ctx)
     }
 
     fn fill(&mut self, original_file: &'a SourceFile, offset: TextUnit) {
diff --git a/crates/ra_ide_api/src/completion/completion_item.rs b/crates/ra_ide_api/src/completion/completion_item.rs
index b75d65de3..11d00f78c 100644
--- a/crates/ra_ide_api/src/completion/completion_item.rs
+++ b/crates/ra_ide_api/src/completion/completion_item.rs
@@ -144,7 +144,7 @@ impl Builder {
         ctx: &CompletionContext,
         resolution: &hir::Resolution,
     ) -> Builder {
-        let resolved = resolution.def_id.and_then(|d| d.resolve(ctx.db).ok());
+        let resolved = resolution.def_id.map(|d| d.resolve(ctx.db));
         let kind = match resolved {
             PerNs {
                 types: Some(hir::Def::Module(..)),