4 files changed, 41 insertions, 27 deletions

diff --git a/crates/completion/src/completions/unqualified_path.rs b/crates/completion/src/completions/unqualified_path.rs
index 86c143b63..3bd776905 100644
--- a/crates/completion/src/completions/unqualified_path.rs
+++ b/crates/completion/src/completions/unqualified_path.rs
@@ -44,7 +44,9 @@ pub(crate) fn complete_unqualified_path(acc: &mut Completions, ctx: &CompletionC
         acc.add_resolution(ctx, name.to_string(), &res)
     });
 
-    fuzzy_completion(acc, ctx).unwrap_or_default()
+    if ctx.config.enable_experimental_completions {
+        fuzzy_completion(acc, ctx).unwrap_or_default()
+    }
 }
 
 fn complete_enum_variants(acc: &mut Completions, ctx: &CompletionContext, ty: &Type) {
@@ -79,32 +81,34 @@ fn fuzzy_completion(acc: &mut Completions, ctx: &CompletionContext) -> Option<()
 
     let potential_import_name = ctx.token.to_string();
 
-    let possible_imports =
-        imports_locator::find_similar_imports(&ctx.sema, ctx.krate?, &potential_import_name, 400)
-            .filter_map(|import_candidate| match import_candidate {
-                // when completing outside the use declaration, modules are pretty useless
-                // and tend to bloat the completion suggestions a lot
-                Either::Left(ModuleDef::Module(_)) => None,
-                Either::Left(module_def) => Some((
-                    current_module.find_use_path(ctx.db, module_def)?,
-                    ScopeDef::ModuleDef(module_def),
-                )),
-                Either::Right(macro_def) => Some((
-                    current_module.find_use_path(ctx.db, macro_def)?,
-                    ScopeDef::MacroDef(macro_def),
-                )),
-            })
-            .filter(|(mod_path, _)| mod_path.len() > 1)
-            .filter_map(|(import_path, definition)| {
-                render_resolution_with_import(
-                    RenderContext::new(ctx),
-                    import_path.clone(),
-                    import_scope.clone(),
-                    ctx.config.merge,
-                    &definition,
-                )
-            })
-            .take(20);
+    let possible_imports = imports_locator::find_similar_imports(
+        &ctx.sema,
+        ctx.krate?,
+        &potential_import_name,
+        50,
+        true,
+    )
+    .filter_map(|import_candidate| {
+        Some(match import_candidate {
+            Either::Left(module_def) => {
+                (current_module.find_use_path(ctx.db, module_def)?, ScopeDef::ModuleDef(module_def))
+            }
+            Either::Right(macro_def) => {
+                (current_module.find_use_path(ctx.db, macro_def)?, ScopeDef::MacroDef(macro_def))
+            }
+        })
+    })
+    .filter(|(mod_path, _)| mod_path.len() > 1)
+    .take(20)
+    .filter_map(|(import_path, definition)| {
+        render_resolution_with_import(
+            RenderContext::new(ctx),
+            import_path.clone(),
+            import_scope.clone(),
+            ctx.config.merge,
+            &definition,
+        )
+    });
 
     acc.add_all(possible_imports);
     Some(())
diff --git a/crates/completion/src/config.rs b/crates/completion/src/config.rs
index 82874ff25..f50735372 100644
--- a/crates/completion/src/config.rs
+++ b/crates/completion/src/config.rs
@@ -9,6 +9,7 @@ use assists::utils::MergeBehaviour;
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub struct CompletionConfig {
     pub enable_postfix_completions: bool,
+    pub enable_experimental_completions: bool,
     pub add_call_parenthesis: bool,
     pub add_call_argument_snippets: bool,
     pub snippet_cap: Option<SnippetCap>,
@@ -30,6 +31,7 @@ impl Default for CompletionConfig {
     fn default() -> Self {
         CompletionConfig {
             enable_postfix_completions: true,
+            enable_experimental_completions: true,
             add_call_parenthesis: true,
             add_call_argument_snippets: true,
             snippet_cap: Some(SnippetCap { _private: () }),
diff --git a/crates/completion/src/lib.rs b/crates/completion/src/lib.rs
index cb6e0554e..aecc1378b 100644
--- a/crates/completion/src/lib.rs
+++ b/crates/completion/src/lib.rs
@@ -67,6 +67,13 @@ pub use crate::{
 //     fn test_name() {}
 // }
 // ```
+//
+// And experimental completions, enabled with the `rust-analyzer.completion.enableExperimental` setting.
+// This flag enables or disables:
+//
+// - Auto import: additional completion options with automatic `use` import and options from all project importable items, matched for the input
+//
+// Experimental completions might cause issues with performance and completion list look.
 
 /// Main entry point for completion. We run completion as a two-phase process.
 ///
diff --git a/crates/completion/src/render.rs b/crates/completion/src/render.rs
index e892d4de8..bce02f577 100644
--- a/crates/completion/src/render.rs
+++ b/crates/completion/src/render.rs
@@ -150,6 +150,7 @@ impl<'a> Render<'a> {
         import_data: Option<(ModPath, ImportScope, Option<MergeBehaviour>)>,
         resolution: &ScopeDef,
     ) -> Option<CompletionItem> {
+        let _p = profile::span("render_resolution");
         use hir::ModuleDef::*;
 
         let completion_kind = match resolution {