Added a utility function that can be used to determine the missing impl items.

2 files changed, 19 insertions, 115 deletions

diff --git a/crates/ra_ide/src/completion.rs b/crates/ra_ide/src/completion.rs
index 4f24cd1f9..4bdc6ba23 100644
--- a/crates/ra_ide/src/completion.rs
+++ b/crates/ra_ide/src/completion.rs
@@ -76,6 +76,6 @@ pub(crate) fn completions(db: &RootDatabase, position: FilePosition) -> Option<C
     complete_postfix::complete_postfix(&mut acc, &ctx);
     complete_macro_in_item_position::complete_macro_in_item_position(&mut acc, &ctx);
     complete_trait_impl::complete_trait_impl(&mut acc, &ctx);
-    
+
     Some(acc)
 }
diff --git a/crates/ra_ide/src/completion/complete_trait_impl.rs b/crates/ra_ide/src/completion/complete_trait_impl.rs
index 0175f5e55..e2854ee97 100644
--- a/crates/ra_ide/src/completion/complete_trait_impl.rs
+++ b/crates/ra_ide/src/completion/complete_trait_impl.rs
@@ -1,124 +1,27 @@
-use crate::completion::{CompletionContext, Completions, CompletionItem, CompletionKind, CompletionItemKind};
+use crate::completion::{
+    CompletionContext, CompletionItem, CompletionItemKind, CompletionKind, Completions,
+};
 
-use ra_syntax::ast::{self, NameOwner, AstNode};
-
-use hir::{self, db::HirDatabase, Docs};
+use hir::{self, Docs};
 
+use ra_assists::utils::get_missing_impl_items;
 
 pub(crate) fn complete_trait_impl(acc: &mut Completions, ctx: &CompletionContext) {
     let impl_block = ctx.impl_block.as_ref();
     let item_list = impl_block.and_then(|i| i.item_list());
 
-    if item_list.is_none() 
-    || impl_block.is_none() 
-    || ctx.function_syntax.is_some() {
+    if item_list.is_none() || impl_block.is_none() || ctx.function_syntax.is_some() {
         return;
     }
 
-    let item_list = item_list.unwrap();
     let impl_block = impl_block.unwrap();
 
-    let target_trait = resolve_target_trait(ctx.db, &ctx.analyzer, &impl_block);
-    if target_trait.is_none() {
-        return;
-    }
-
-    let target_trait = target_trait.unwrap();
-
-    let trait_items = target_trait.items(ctx.db);
-    let missing_items = trait_items
-        .iter()
-        .filter(|i| {
-            match i {
-                hir::AssocItem::Function(f) => {
-                    let f_name = f.name(ctx.db).to_string();
-
-                    item_list
-                        .impl_items()
-                        .find(|impl_item| {
-                            match impl_item {
-                                ast::ImplItem::FnDef(impl_f) => {
-                                    if let Some(n) = impl_f.name() { 
-                                        f_name == n.syntax().to_string()
-                                    } else { 
-                                        false
-                                    }
-                                },
-                                _ => false
-                            }
-                        }).is_none()
-                },
-                hir::AssocItem::Const(c) => {
-                    let c_name = c.name(ctx.db)
-                        .map(|f| f.to_string());
-
-                    if c_name.is_none() {
-                        return false;
-                    }
-
-                    let c_name = c_name.unwrap();
-
-                    item_list
-                        .impl_items()
-                        .find(|impl_item| {
-                            match impl_item {
-                                ast::ImplItem::ConstDef(c) => {
-                                    if let Some(n) = c.name() { 
-                                        c_name == n.syntax().to_string()
-                                    } else { 
-                                        false
-                                    }
-                                },
-                                _ => false
-                            }
-                        }).is_none()
-                },
-                hir::AssocItem::TypeAlias(t) => {
-                    let t_name = t.name(ctx.db).to_string();
-
-                    item_list
-                        .impl_items()
-                        .find(|impl_item| {
-                            match impl_item {
-                                ast::ImplItem::TypeAliasDef(t) => {
-                                    if let Some(n) = t.name() { 
-                                        t_name == n.syntax().to_string()
-                                    } else { 
-                                        false
-                                    }
-                                },
-                                _ => false
-                            }
-                        }).is_none()
-                }
-            }
-        });
-
-    for item in missing_items {
+    for item in get_missing_impl_items(ctx.db, &ctx.analyzer, impl_block) {
         match item {
-            hir::AssocItem::Function(f) => add_function_impl(acc, ctx, f),
-            hir::AssocItem::TypeAlias(t) => add_type_alias_impl(acc, ctx, t),
-            _ => {},
-        }
-    }
-}
-
-fn resolve_target_trait(
-    db: &impl HirDatabase,
-    analyzer: &hir::SourceAnalyzer,
-    impl_block: &ast::ImplBlock
-) -> Option<hir::Trait> {
-    let ast_path = impl_block
-        .target_trait()
-        .map(|it| it.syntax().clone())
-        .and_then(ast::PathType::cast)?
-        .path()?;
-
-    match analyzer.resolve_path(db, &ast_path) {
-        Some(hir::PathResolution::Def(hir::ModuleDef::Trait(def))) => {
-            Some(def)
+            hir::AssocItem::Function(f) => add_function_impl(acc, ctx, &f),
+            hir::AssocItem::TypeAlias(t) => add_type_alias_impl(acc, ctx, &t),
+            _ => {}
         }
-        _ => None,
     }
 }
 
@@ -144,20 +47,21 @@ fn add_function_impl(acc: &mut Completions, ctx: &CompletionContext, func: &hir:
     } else {
         CompletionItemKind::Function
     };
-    
+
     let snippet = {
         let mut s = format!("{}", display);
         s.push_str(" {}");
         s
     };
 
-    builder
-        .insert_text(snippet)
-        .kind(completion_kind)
-        .add_to(acc);
+    builder.insert_text(snippet).kind(completion_kind).add_to(acc);
 }
 
-fn add_type_alias_impl(acc: &mut Completions, ctx: &CompletionContext, type_alias: &hir::TypeAlias) {
+fn add_type_alias_impl(
+    acc: &mut Completions,
+    ctx: &CompletionContext,
+    type_alias: &hir::TypeAlias,
+) {
     let snippet = format!("type {} = ", type_alias.name(ctx.db).to_string());
 
     CompletionItem::new(CompletionKind::Magic, ctx.source_range(), snippet.clone())
@@ -290,4 +194,4 @@ mod tests {
         ]
         "###);
     }
-}
\ No newline at end of file
+}