9 files changed, 413 insertions, 300 deletions

diff --git a/crates/completion/src/completions.rs b/crates/completion/src/completions.rs
index 00c9e76f0..c3ce6e51d 100644
--- a/crates/completion/src/completions.rs
+++ b/crates/completion/src/completions.rs
@@ -13,6 +13,7 @@ pub(crate) mod postfix;
 pub(crate) mod macro_in_item_position;
 pub(crate) mod trait_impl;
 pub(crate) mod mod_;
+pub(crate) mod flyimport;
 
 use hir::{ModPath, ScopeDef, Type};
 
diff --git a/crates/completion/src/completions/flyimport.rs b/crates/completion/src/completions/flyimport.rs
new file mode 100644
index 000000000..222809638
--- /dev/null
+++ b/crates/completion/src/completions/flyimport.rs
@@ -0,0 +1,291 @@
+//! Feature: completion with imports-on-the-fly
+//!
+//! When completing names in the current scope, proposes additional imports from other modules or crates,
+//! if they can be qualified in the scope and their name contains all symbols from the completion input
+//! (case-insensitive, in any order or places).
+//!
+//! ```
+//! fn main() {
+//!     pda$0
+//! }
+//! # pub mod std { pub mod marker { pub struct PhantomData { } } }
+//! ```
+//! ->
+//! ```
+//! use std::marker::PhantomData;
+//!
+//! fn main() {
+//!     PhantomData
+//! }
+//! # pub mod std { pub mod marker { pub struct PhantomData { } } }
+//! ```
+//!
+//! .Fuzzy search details
+//!
+//! To avoid an excessive amount of the results returned, completion input is checked for inclusion in the names only
+//! (i.e. in `HashMap` in the `std::collections::HashMap` path).
+//! For the same reasons, avoids searching for any imports for inputs with their length less that 2 symbols.
+//!
+//! .Import configuration
+//!
+//! It is possible to configure how use-trees are merged with the `importMergeBehavior` setting.
+//! Mimics the corresponding behavior of the `Auto Import` feature.
+//!
+//! .LSP and performance implications
+//!
+//! The feature is enabled only if the LSP client supports LSP protocol version 3.16+ and reports the `additionalTextEdits`
+//! (case sensitive) resolve client capability in its client capabilities.
+//! This way the server is able to defer the costly computations, doing them for a selected completion item only.
+//! For clients with no such support, all edits have to be calculated on the completion request, including the fuzzy search completion ones,
+//! which might be slow ergo the feature is automatically disabled.
+//!
+//! .Feature toggle
+//!
+//! The feature can be forcefully turned off in the settings with the `rust-analyzer.completion.enableAutoimportCompletions` flag.
+//! Note that having this flag set to `true` does not guarantee that the feature is enabled: your client needs to have the corredponding
+//! capability enabled.
+
+use either::Either;
+use hir::{ModPath, ScopeDef};
+use ide_db::{helpers::insert_use::ImportScope, imports_locator};
+use syntax::AstNode;
+use test_utils::mark;
+
+use crate::{
+    context::CompletionContext,
+    render::{render_resolution_with_import, RenderContext},
+    ImportEdit,
+};
+
+use super::Completions;
+
+pub(crate) fn import_on_the_fly(acc: &mut Completions, ctx: &CompletionContext) -> Option<()> {
+    if !ctx.config.enable_autoimport_completions {
+        return None;
+    }
+    if ctx.attribute_under_caret.is_some() || ctx.mod_declaration_under_caret.is_some() {
+        return None;
+    }
+    let potential_import_name = ctx.token.to_string();
+    if potential_import_name.len() < 2 {
+        return None;
+    }
+    let _p = profile::span("import_on_the_fly").detail(|| potential_import_name.to_string());
+
+    let current_module = ctx.scope.module()?;
+    let anchor = ctx.name_ref_syntax.as_ref()?;
+    let import_scope = ImportScope::find_insert_use_container(anchor.syntax(), &ctx.sema)?;
+
+    let user_input_lowercased = potential_import_name.to_lowercase();
+    let mut all_mod_paths = imports_locator::find_similar_imports(
+        &ctx.sema,
+        ctx.krate?,
+        Some(40),
+        potential_import_name,
+        true,
+        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)
+    .collect::<Vec<_>>();
+
+    all_mod_paths.sort_by_cached_key(|(mod_path, _)| {
+        compute_fuzzy_completion_order_key(mod_path, &user_input_lowercased)
+    });
+
+    acc.add_all(all_mod_paths.into_iter().filter_map(|(import_path, definition)| {
+        render_resolution_with_import(
+            RenderContext::new(ctx),
+            ImportEdit { import_path, import_scope: import_scope.clone() },
+            &definition,
+        )
+    }));
+    Some(())
+}
+
+fn compute_fuzzy_completion_order_key(
+    proposed_mod_path: &ModPath,
+    user_input_lowercased: &str,
+) -> usize {
+    mark::hit!(certain_fuzzy_order_test);
+    let proposed_import_name = match proposed_mod_path.segments.last() {
+        Some(name) => name.to_string().to_lowercase(),
+        None => return usize::MAX,
+    };
+    match proposed_import_name.match_indices(user_input_lowercased).next() {
+        Some((first_matching_index, _)) => first_matching_index,
+        None => usize::MAX,
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use expect_test::{expect, Expect};
+    use test_utils::mark;
+
+    use crate::{
+        item::CompletionKind,
+        test_utils::{check_edit, completion_list},
+    };
+
+    fn check(ra_fixture: &str, expect: Expect) {
+        let actual = completion_list(ra_fixture, CompletionKind::Magic);
+        expect.assert_eq(&actual);
+    }
+
+    #[test]
+    fn function_fuzzy_completion() {
+        check_edit(
+            "stdin",
+            r#"
+//- /lib.rs crate:dep
+pub mod io {
+    pub fn stdin() {}
+};
+
+//- /main.rs crate:main deps:dep
+fn main() {
+    stdi$0
+}
+"#,
+            r#"
+use dep::io::stdin;
+
+fn main() {
+    stdin()$0
+}
+"#,
+        );
+    }
+
+    #[test]
+    fn macro_fuzzy_completion() {
+        check_edit(
+            "macro_with_curlies!",
+            r#"
+//- /lib.rs crate:dep
+/// Please call me as macro_with_curlies! {}
+#[macro_export]
+macro_rules! macro_with_curlies {
+    () => {}
+}
+
+//- /main.rs crate:main deps:dep
+fn main() {
+    curli$0
+}
+"#,
+            r#"
+use dep::macro_with_curlies;
+
+fn main() {
+    macro_with_curlies! {$0}
+}
+"#,
+        );
+    }
+
+    #[test]
+    fn struct_fuzzy_completion() {
+        check_edit(
+            "ThirdStruct",
+            r#"
+//- /lib.rs crate:dep
+pub struct FirstStruct;
+pub mod some_module {
+    pub struct SecondStruct;
+    pub struct ThirdStruct;
+}
+
+//- /main.rs crate:main deps:dep
+use dep::{FirstStruct, some_module::SecondStruct};
+
+fn main() {
+    this$0
+}
+"#,
+            r#"
+use dep::{FirstStruct, some_module::{SecondStruct, ThirdStruct}};
+
+fn main() {
+    ThirdStruct
+}
+"#,
+        );
+    }
+
+    #[test]
+    fn fuzzy_completions_come_in_specific_order() {
+        mark::check!(certain_fuzzy_order_test);
+        check(
+            r#"
+//- /lib.rs crate:dep
+pub struct FirstStruct;
+pub mod some_module {
+    // already imported, omitted
+    pub struct SecondStruct;
+    // does not contain all letters from the query, omitted
+    pub struct UnrelatedOne;
+    // contains all letters from the query, but not in sequence, displayed last
+    pub struct ThiiiiiirdStruct;
+    // contains all letters from the query, but not in the beginning, displayed second
+    pub struct AfterThirdStruct;
+    // contains all letters from the query in the begginning, displayed first
+    pub struct ThirdStruct;
+}
+
+//- /main.rs crate:main deps:dep
+use dep::{FirstStruct, some_module::SecondStruct};
+
+fn main() {
+    hir$0
+}
+"#,
+            expect![[r#"
+                st dep::some_module::ThirdStruct
+                st dep::some_module::AfterThirdStruct
+                st dep::some_module::ThiiiiiirdStruct
+            "#]],
+        );
+    }
+
+    #[test]
+    fn does_not_propose_names_in_scope() {
+        check(
+            r#"
+//- /lib.rs crate:dep
+pub mod test_mod {
+    pub trait TestTrait {
+        const SPECIAL_CONST: u8;
+        type HumbleType;
+        fn weird_function();
+        fn random_method(&self);
+    }
+    pub struct TestStruct {}
+    impl TestTrait for TestStruct {
+        const SPECIAL_CONST: u8 = 42;
+        type HumbleType = ();
+        fn weird_function() {}
+        fn random_method(&self) {}
+    }
+}
+
+//- /main.rs crate:main deps:dep
+use dep::test_mod::TestStruct;
+fn main() {
+    TestSt$0
+}
+"#,
+            expect![[r#""#]],
+        );
+    }
+}
diff --git a/crates/completion/src/completions/keyword.rs b/crates/completion/src/completions/keyword.rs
index 425a688ff..c1af348dc 100644
--- a/crates/completion/src/completions/keyword.rs
+++ b/crates/completion/src/completions/keyword.rs
@@ -1,6 +1,6 @@
 //! Completes keywords.
 
-use syntax::{ast, SyntaxKind};
+use syntax::SyntaxKind;
 use test_utils::mark;
 
 use crate::{CompletionContext, CompletionItem, CompletionItemKind, CompletionKind, Completions};
@@ -86,8 +86,8 @@ pub(crate) fn complete_expr_keyword(acc: &mut Completions, ctx: &CompletionConte
         add_keyword(ctx, acc, "match", "match $0 {}");
         add_keyword(ctx, acc, "while", "while $0 {}");
         add_keyword(ctx, acc, "loop", "loop {$0}");
-        add_keyword(ctx, acc, "if", "if ");
-        add_keyword(ctx, acc, "if let", "if let ");
+        add_keyword(ctx, acc, "if", "if $0 {}");
+        add_keyword(ctx, acc, "if let", "if let $1 = $0 {}");
     }
 
     if ctx.if_is_prev || ctx.block_expr_parent {
@@ -143,47 +143,49 @@ pub(crate) fn complete_expr_keyword(acc: &mut Completions, ctx: &CompletionConte
         Some(it) => it,
         None => return,
     };
-    acc.add_all(complete_return(ctx, &fn_def, ctx.can_be_stmt));
-}
-
-fn keyword(ctx: &CompletionContext, kw: &str, snippet: &str) -> CompletionItem {
-    let res = CompletionItem::new(CompletionKind::Keyword, ctx.source_range(), kw)
-        .kind(CompletionItemKind::Keyword);
 
-    match ctx.config.snippet_cap {
-        Some(cap) => res.insert_snippet(cap, snippet),
-        _ => res.insert_text(if snippet.contains('$') { kw } else { snippet }),
-    }
-    .build()
+    add_keyword(
+        ctx,
+        acc,
+        "return",
+        match (ctx.can_be_stmt, fn_def.ret_type().is_some()) {
+            (true, true) => "return $0;",
+            (true, false) => "return;",
+            (false, true) => "return $0",
+            (false, false) => "return",
+        },
+    )
 }
 
 fn add_keyword(ctx: &CompletionContext, acc: &mut Completions, kw: &str, snippet: &str) {
-    acc.add(keyword(ctx, kw, snippet));
-}
-
-fn complete_return(
-    ctx: &CompletionContext,
-    fn_def: &ast::Fn,
-    can_be_stmt: bool,
-) -> Option<CompletionItem> {
-    let snip = match (can_be_stmt, fn_def.ret_type().is_some()) {
-        (true, true) => "return $0;",
-        (true, false) => "return;",
-        (false, true) => "return $0",
-        (false, false) => "return",
+    let builder = CompletionItem::new(CompletionKind::Keyword, ctx.source_range(), kw)
+        .kind(CompletionItemKind::Keyword);
+    let builder = match ctx.config.snippet_cap {
+        Some(cap) => {
+            let tmp;
+            let snippet = if snippet.ends_with('}') && ctx.incomplete_let {
+                mark::hit!(let_semi);
+                tmp = format!("{};", snippet);
+                &tmp
+            } else {
+                snippet
+            };
+            builder.insert_snippet(cap, snippet)
+        }
+        None => builder.insert_text(if snippet.contains('$') { kw } else { snippet }),
     };
-    Some(keyword(ctx, "return", snip))
+    acc.add(builder.build());
 }
 
 #[cfg(test)]
 mod tests {
     use expect_test::{expect, Expect};
+    use test_utils::mark;
 
     use crate::{
         test_utils::{check_edit, completion_list},
         CompletionKind,
     };
-    use test_utils::mark;
 
     fn check(ra_fixture: &str, expect: Expect) {
         let actual = completion_list(ra_fixture, CompletionKind::Keyword);
@@ -609,4 +611,50 @@ fn foo() {
             "#]],
         );
     }
+
+    #[test]
+    fn let_semi() {
+        mark::check!(let_semi);
+        check_edit(
+            "match",
+            r#"
+fn main() { let x = $0 }
+"#,
+            r#"
+fn main() { let x = match $0 {}; }
+"#,
+        );
+
+        check_edit(
+            "if",
+            r#"
+fn main() {
+    let x = $0
+    let y = 92;
+}
+"#,
+            r#"
+fn main() {
+    let x = if $0 {};
+    let y = 92;
+}
+"#,
+        );
+
+        check_edit(
+            "loop",
+            r#"
+fn main() {
+    let x = $0
+    bar();
+}
+"#,
+            r#"
+fn main() {
+    let x = loop {$0};
+    bar();
+}
+"#,
+        );
+    }
 }
diff --git a/crates/completion/src/completions/unqualified_path.rs b/crates/completion/src/completions/unqualified_path.rs
index 53e1391f3..ac5596ca4 100644
--- a/crates/completion/src/completions/unqualified_path.rs
+++ b/crates/completion/src/completions/unqualified_path.rs
@@ -2,17 +2,11 @@
 
 use std::iter;
 
-use either::Either;
-use hir::{Adt, ModPath, ModuleDef, ScopeDef, Type};
-use ide_db::helpers::insert_use::ImportScope;
-use ide_db::imports_locator;
+use hir::{Adt, ModuleDef, ScopeDef, Type};
 use syntax::AstNode;
 use test_utils::mark;
 
-use crate::{
-    render::{render_resolution_with_import, RenderContext},
-    CompletionContext, Completions, ImportEdit,
-};
+use crate::{CompletionContext, Completions};
 
 pub(crate) fn complete_unqualified_path(acc: &mut Completions, ctx: &CompletionContext) {
     if !(ctx.is_trivial_path || ctx.is_pat_binding_or_const) {
@@ -45,10 +39,6 @@ pub(crate) fn complete_unqualified_path(acc: &mut Completions, ctx: &CompletionC
         }
         acc.add_resolution(ctx, name.to_string(), &res)
     });
-
-    if ctx.config.enable_autoimport_completions {
-        fuzzy_completion(acc, ctx);
-    }
 }
 
 fn complete_enum_variants(acc: &mut Completions, ctx: &CompletionContext, ty: &Type) {
@@ -77,124 +67,13 @@ fn complete_enum_variants(acc: &mut Completions, ctx: &CompletionContext, ty: &T
     }
 }
 
-// Feature: Fuzzy Completion and Autoimports
-//
-// When completing names in the current scope, proposes additional imports from other modules or crates,
-// if they can be qualified in the scope and their name contains all symbols from the completion input
-// (case-insensitive, in any order or places).
-//
-// ```
-// fn main() {
-//     pda$0
-// }
-// # pub mod std { pub mod marker { pub struct PhantomData { } } }
-// ```
-// ->
-// ```
-// use std::marker::PhantomData;
-//
-// fn main() {
-//     PhantomData
-// }
-// # pub mod std { pub mod marker { pub struct PhantomData { } } }
-// ```
-//
-// .Fuzzy search details
-//
-// To avoid an excessive amount of the results returned, completion input is checked for inclusion in the names only
-// (i.e. in `HashMap` in the `std::collections::HashMap` path).
-// For the same reasons, avoids searching for any imports for inputs with their length less that 2 symbols.
-//
-// .Merge Behavior
-//
-// It is possible to configure how use-trees are merged with the `importMergeBehavior` setting.
-// Mimics the corresponding behavior of the `Auto Import` feature.
-//
-// .LSP and performance implications
-//
-// The feature is enabled only if the LSP client supports LSP protocol version 3.16+ and reports the `additionalTextEdits`
-// (case sensitive) resolve client capability in its client capabilities.
-// This way the server is able to defer the costly computations, doing them for a selected completion item only.
-// For clients with no such support, all edits have to be calculated on the completion request, including the fuzzy search completion ones,
-// which might be slow ergo the feature is automatically disabled.
-//
-// .Feature toggle
-//
-// The feature can be forcefully turned off in the settings with the `rust-analyzer.completion.enableAutoimportCompletions` flag.
-// Note that having this flag set to `true` does not guarantee that the feature is enabled: your client needs to have the corredponding
-// capability enabled.
-fn fuzzy_completion(acc: &mut Completions, ctx: &CompletionContext) -> Option<()> {
-    let potential_import_name = ctx.token.to_string();
-    let _p = profile::span("fuzzy_completion").detail(|| potential_import_name.clone());
-
-    if potential_import_name.len() < 2 {
-        return None;
-    }
-
-    let current_module = ctx.scope.module()?;
-    let anchor = ctx.name_ref_syntax.as_ref()?;
-    let import_scope = ImportScope::find_insert_use_container(anchor.syntax(), &ctx.sema)?;
-
-    let user_input_lowercased = potential_import_name.to_lowercase();
-    let mut all_mod_paths = imports_locator::find_similar_imports(
-        &ctx.sema,
-        ctx.krate?,
-        Some(40),
-        potential_import_name,
-        true,
-        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)
-    .collect::<Vec<_>>();
-
-    all_mod_paths.sort_by_cached_key(|(mod_path, _)| {
-        compute_fuzzy_completion_order_key(mod_path, &user_input_lowercased)
-    });
-
-    acc.add_all(all_mod_paths.into_iter().filter_map(|(import_path, definition)| {
-        render_resolution_with_import(
-            RenderContext::new(ctx),
-            ImportEdit { import_path, import_scope: import_scope.clone() },
-            &definition,
-        )
-    }));
-    Some(())
-}
-
-fn compute_fuzzy_completion_order_key(
-    proposed_mod_path: &ModPath,
-    user_input_lowercased: &str,
-) -> usize {
-    mark::hit!(certain_fuzzy_order_test);
-    let proposed_import_name = match proposed_mod_path.segments.last() {
-        Some(name) => name.to_string().to_lowercase(),
-        None => return usize::MAX,
-    };
-    match proposed_import_name.match_indices(user_input_lowercased).next() {
-        Some((first_matching_index, _)) => first_matching_index,
-        None => usize::MAX,
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use expect_test::{expect, Expect};
     use test_utils::mark;
 
     use crate::{
-        test_utils::{
-            check_edit, check_edit_with_config, completion_list_with_config, TEST_CONFIG,
-        },
+        test_utils::{check_edit, completion_list_with_config, TEST_CONFIG},
         CompletionConfig, CompletionKind,
     };
 
@@ -855,128 +734,4 @@ impl My$0
             "#]],
         )
     }
-
-    #[test]
-    fn function_fuzzy_completion() {
-        check_edit_with_config(
-            TEST_CONFIG,
-            "stdin",
-            r#"
-//- /lib.rs crate:dep
-pub mod io {
-    pub fn stdin() {}
-};
-
-//- /main.rs crate:main deps:dep
-fn main() {
-    stdi$0
-}
-"#,
-            r#"
-use dep::io::stdin;
-
-fn main() {
-    stdin()$0
-}
-"#,
-        );
-    }
-
-    #[test]
-    fn macro_fuzzy_completion() {
-        check_edit_with_config(
-            TEST_CONFIG,
-            "macro_with_curlies!",
-            r#"
-//- /lib.rs crate:dep
-/// Please call me as macro_with_curlies! {}
-#[macro_export]
-macro_rules! macro_with_curlies {
-    () => {}
-}
-
-//- /main.rs crate:main deps:dep
-fn main() {
-    curli$0
-}
-"#,
-            r#"
-use dep::macro_with_curlies;
-
-fn main() {
-    macro_with_curlies! {$0}
-}
-"#,
-        );
-    }
-
-    #[test]
-    fn struct_fuzzy_completion() {
-        check_edit_with_config(
-            TEST_CONFIG,
-            "ThirdStruct",
-            r#"
-//- /lib.rs crate:dep
-pub struct FirstStruct;
-pub mod some_module {
-    pub struct SecondStruct;
-    pub struct ThirdStruct;
-}
-
-//- /main.rs crate:main deps:dep
-use dep::{FirstStruct, some_module::SecondStruct};
-
-fn main() {
-    this$0
-}
-"#,
-            r#"
-use dep::{FirstStruct, some_module::{SecondStruct, ThirdStruct}};
-
-fn main() {
-    ThirdStruct
-}
-"#,
-        );
-    }
-
-    #[test]
-    fn fuzzy_completions_come_in_specific_order() {
-        mark::check!(certain_fuzzy_order_test);
-        check_with_config(
-            TEST_CONFIG,
-            r#"
-//- /lib.rs crate:dep
-pub struct FirstStruct;
-pub mod some_module {
-    // already imported, omitted
-    pub struct SecondStruct;
-    // does not contain all letters from the query, omitted
-    pub struct UnrelatedOne;
-    // contains all letters from the query, but not in sequence, displayed last
-    pub struct ThiiiiiirdStruct;
-    // contains all letters from the query, but not in the beginning, displayed second
-    pub struct AfterThirdStruct;
-    // contains all letters from the query in the begginning, displayed first
-    pub struct ThirdStruct;
-}
-
-//- /main.rs crate:main deps:dep
-use dep::{FirstStruct, some_module::SecondStruct};
-
-fn main() {
-    hir$0
-}
-"#,
-            expect![[r#"
-                fn main()           fn main()
-                st SecondStruct
-                st FirstStruct
-                md dep
-                st dep::some_module::ThirdStruct
-                st dep::some_module::AfterThirdStruct
-                st dep::some_module::ThiiiiiirdStruct
-            "#]],
-        );
-    }
 }
diff --git a/crates/completion/src/config.rs b/crates/completion/src/config.rs
index b4439b7d1..58fc700f3 100644
--- a/crates/completion/src/config.rs
+++ b/crates/completion/src/config.rs
@@ -4,7 +4,7 @@
 //! module, and we use to statically check that we only produce snippet
 //! completions if we are allowed to.
 
-use ide_db::helpers::{insert_use::MergeBehavior, SnippetCap};
+use ide_db::helpers::{insert_use::InsertUseConfig, SnippetCap};
 
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub struct CompletionConfig {
@@ -13,5 +13,5 @@ pub struct CompletionConfig {
     pub add_call_parenthesis: bool,
     pub add_call_argument_snippets: bool,
     pub snippet_cap: Option<SnippetCap>,
-    pub merge: Option<MergeBehavior>,
+    pub insert_use: InsertUseConfig,
 }
diff --git a/crates/completion/src/context.rs b/crates/completion/src/context.rs
index ebf28e887..b1e8eba85 100644
--- a/crates/completion/src/context.rs
+++ b/crates/completion/src/context.rs
@@ -4,10 +4,8 @@ use hir::{Local, ScopeDef, Semantics, SemanticsScope, Type};
 use ide_db::base_db::{FilePosition, SourceDatabase};
 use ide_db::{call_info::ActiveParameter, RootDatabase};
 use syntax::{
-    algo::{find_covering_element, find_node_at_offset},
-    ast, match_ast, AstNode, NodeOrToken,
-    SyntaxKind::*,
-    SyntaxNode, SyntaxToken, TextRange, TextSize,
+    algo::find_node_at_offset, ast, match_ast, AstNode, NodeOrToken, SyntaxKind::*, SyntaxNode,
+    SyntaxToken, TextRange, TextSize,
 };
 use test_utils::mark;
 use text_edit::Indel;
@@ -92,6 +90,7 @@ pub(crate) struct CompletionContext<'a> {
     pub(super) has_item_list_or_source_file_parent: bool,
     pub(super) for_is_prev2: bool,
     pub(super) fn_is_prev: bool,
+    pub(super) incomplete_let: bool,
     pub(super) locals: Vec<(String, Local)>,
 }
 
@@ -132,9 +131,9 @@ impl<'a> CompletionContext<'a> {
             scope,
             db,
             config,
+            position,
             original_token,
             token,
-            position,
             krate,
             expected_type: None,
             name_ref_syntax: None,
@@ -155,30 +154,31 @@ impl<'a> CompletionContext<'a> {
             is_expr: false,
             is_new_item: false,
             dot_receiver: None,
+            dot_receiver_is_ambiguous_float_literal: false,
             is_call: false,
             is_pattern_call: false,
             is_macro_call: false,
             is_path_type: false,
             has_type_args: false,
-            dot_receiver_is_ambiguous_float_literal: false,
             attribute_under_caret: None,
             mod_declaration_under_caret: None,
             unsafe_is_prev: false,
-            in_loop_body: false,
-            ref_pat_parent: false,
-            bind_pat_parent: false,
+            if_is_prev: false,
             block_expr_parent: false,
+            bind_pat_parent: false,
+            ref_pat_parent: false,
+            in_loop_body: false,
             has_trait_parent: false,
             has_impl_parent: false,
             inside_impl_trait_block: false,
             has_field_list_parent: false,
             trait_as_prev_sibling: false,
             impl_as_prev_sibling: false,
-            if_is_prev: false,
             is_match_arm: false,
             has_item_list_or_source_file_parent: false,
             for_is_prev2: false,
             fn_is_prev: false,
+            incomplete_let: false,
             locals,
         };
 
@@ -270,6 +270,10 @@ impl<'a> CompletionContext<'a> {
                 .filter(|module| module.item_list().is_none());
         self.for_is_prev2 = for_is_prev2(syntax_element.clone());
         self.fn_is_prev = fn_is_prev(syntax_element.clone());
+        self.incomplete_let =
+            syntax_element.ancestors().take(6).find_map(ast::LetStmt::cast).map_or(false, |it| {
+                it.syntax().text_range().end() == syntax_element.text_range().end()
+            });
     }
 
     fn fill(
@@ -507,7 +511,7 @@ impl<'a> CompletionContext<'a> {
 }
 
 fn find_node_with_range<N: AstNode>(syntax: &SyntaxNode, range: TextRange) -> Option<N> {
-    find_covering_element(syntax, range).ancestors().find_map(N::cast)
+    syntax.covering_element(range).ancestors().find_map(N::cast)
 }
 
 fn is_node<N: AstNode>(node: &SyntaxNode) -> bool {
diff --git a/crates/completion/src/lib.rs b/crates/completion/src/lib.rs
index 6cba88a6b..ee1b822e7 100644
--- a/crates/completion/src/lib.rs
+++ b/crates/completion/src/lib.rs
@@ -127,6 +127,7 @@ pub fn completions(
     completions::macro_in_item_position::complete_macro_in_item_position(&mut acc, &ctx);
     completions::trait_impl::complete_trait_impl(&mut acc, &ctx);
     completions::mod_::complete_mod(&mut acc, &ctx);
+    completions::flyimport::import_on_the_fly(&mut acc, &ctx);
 
     Some(acc)
 }
@@ -153,7 +154,9 @@ pub fn resolve_completion_edits(
         })
         .find(|mod_path| mod_path.to_string() == full_import_path)?;
 
-    ImportEdit { import_path, import_scope }.to_text_edit(config.merge).map(|edit| vec![edit])
+    ImportEdit { import_path, import_scope }
+        .to_text_edit(config.insert_use.merge)
+        .map(|edit| vec![edit])
 }
 
 #[cfg(test)]
diff --git a/crates/completion/src/render.rs b/crates/completion/src/render.rs
index e93c59f71..820dd01d1 100644
--- a/crates/completion/src/render.rs
+++ b/crates/completion/src/render.rs
@@ -51,11 +51,16 @@ pub(crate) fn render_resolution_with_import<'a>(
     import_edit: ImportEdit,
     resolution: &ScopeDef,
 ) -> Option<CompletionItem> {
-    Render::new(ctx).render_resolution(
-        import_edit.import_path.segments.last()?.to_string(),
-        Some(import_edit),
-        resolution,
-    )
+    Render::new(ctx)
+        .render_resolution(
+            import_edit.import_path.segments.last()?.to_string(),
+            Some(import_edit),
+            resolution,
+        )
+        .map(|mut item| {
+            item.completion_kind = CompletionKind::Magic;
+            item
+        })
 }
 
 /// Interface for data and methods required for items rendering.
diff --git a/crates/completion/src/test_utils.rs b/crates/completion/src/test_utils.rs
index 3f4b9d4ac..6ea6da989 100644
--- a/crates/completion/src/test_utils.rs
+++ b/crates/completion/src/test_utils.rs
@@ -1,9 +1,12 @@
 //! Runs completion for testing purposes.
 
-use hir::Semantics;
+use hir::{PrefixKind, Semantics};
 use ide_db::{
     base_db::{fixture::ChangeFixture, FileLoader, FilePosition},
-    helpers::{insert_use::MergeBehavior, SnippetCap},
+    helpers::{
+        insert_use::{InsertUseConfig, MergeBehavior},
+        SnippetCap,
+    },
     RootDatabase,
 };
 use itertools::Itertools;
@@ -19,7 +22,10 @@ pub(crate) const TEST_CONFIG: CompletionConfig = CompletionConfig {
     add_call_parenthesis: true,
     add_call_argument_snippets: true,
     snippet_cap: SnippetCap::new(true),
-    merge: Some(MergeBehavior::Full),
+    insert_use: InsertUseConfig {
+        merge: Some(MergeBehavior::Full),
+        prefix_kind: PrefixKind::Plain,
+    },
 };
 
 /// Creates analysis from a multi-file fixture, returns positions marked with $0.
@@ -110,7 +116,7 @@ pub(crate) fn check_edit_with_config(
 
     let mut combined_edit = completion.text_edit().to_owned();
     if let Some(import_text_edit) =
-        completion.import_to_add().and_then(|edit| edit.to_text_edit(config.merge))
+        completion.import_to_add().and_then(|edit| edit.to_text_edit(config.insert_use.merge))
     {
         combined_edit.union(import_text_edit).expect(
             "Failed to apply completion resolve changes: change ranges overlap, but should not",