39 files changed, 428 insertions, 320 deletions

diff --git a/Cargo.lock b/Cargo.lock
index f39cd01c3..9346edc96 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1139,6 +1139,37 @@ dependencies = [
  "ra_db",
  "ra_fmt",
  "ra_hir",
+ "ra_ide_db",
+ "ra_prof",
+ "ra_syntax",
+ "ra_text_edit",
+ "rand 0.7.3",
+ "rayon",
+ "rustc-hash",
+ "superslice",
+ "test_utils",
+ "unicase",
+]
+
+[[package]]
+name = "ra_ide_db"
+version = "0.1.0"
+dependencies = [
+ "either",
+ "format-buf",
+ "fst",
+ "indexmap",
+ "insta",
+ "itertools",
+ "join_to_string",
+ "log",
+ "once_cell",
+ "proptest",
+ "ra_assists",
+ "ra_cfg",
+ "ra_db",
+ "ra_fmt",
+ "ra_hir",
  "ra_prof",
  "ra_syntax",
  "ra_text_edit",
diff --git a/crates/ra_ide/Cargo.toml b/crates/ra_ide/Cargo.toml
index 53817d1f7..9ace35229 100644
--- a/crates/ra_ide/Cargo.toml
+++ b/crates/ra_ide/Cargo.toml
@@ -28,6 +28,7 @@ once_cell = "1.2.0"
 ra_syntax = { path = "../ra_syntax" }
 ra_text_edit = { path = "../ra_text_edit" }
 ra_db = { path = "../ra_db" }
+ra_ide_db = { path = "../ra_ide_db" }
 ra_cfg = { path = "../ra_cfg" }
 ra_fmt = { path = "../ra_fmt" }
 ra_prof = { path = "../ra_prof" }
diff --git a/crates/ra_ide/src/assists.rs b/crates/ra_ide/src/assists.rs
index c43c45c65..f26047570 100644
--- a/crates/ra_ide/src/assists.rs
+++ b/crates/ra_ide/src/assists.rs
@@ -1,13 +1,13 @@
 //! FIXME: write short doc here
 
+use either::Either;
+use ra_assists::{AssistAction, AssistLabel};
 use ra_db::{FilePosition, FileRange};
+use ra_ide_db::RootDatabase;
+
+use crate::{imports_locator::ImportsLocatorIde, FileId, SourceChange, SourceFileEdit};
 
-use crate::{
-    db::RootDatabase, imports_locator::ImportsLocatorIde, FileId, SourceChange, SourceFileEdit,
-};
-use either::Either;
 pub use ra_assists::AssistId;
-use ra_assists::{AssistAction, AssistLabel};
 
 #[derive(Debug)]
 pub struct Assist {
diff --git a/crates/ra_ide/src/call_hierarchy.rs b/crates/ra_ide/src/call_hierarchy.rs
index aa5d60c7b..f984f40ad 100644
--- a/crates/ra_ide/src/call_hierarchy.rs
+++ b/crates/ra_ide/src/call_hierarchy.rs
@@ -3,6 +3,7 @@
 use indexmap::IndexMap;
 
 use hir::db::AstDatabase;
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     ast::{self, DocCommentsOwner},
     match_ast, AstNode, TextRange,
@@ -10,7 +11,6 @@ use ra_syntax::{
 
 use crate::{
     call_info::FnCallNode,
-    db::RootDatabase,
     display::{ShortLabel, ToNav},
     expand::descend_into_macros,
     goto_definition, references, FilePosition, NavigationTarget, RangeInfo,
diff --git a/crates/ra_ide/src/call_info.rs b/crates/ra_ide/src/call_info.rs
index 72a68522e..f2b29306e 100644
--- a/crates/ra_ide/src/call_info.rs
+++ b/crates/ra_ide/src/call_info.rs
@@ -1,15 +1,13 @@
 //! FIXME: write short doc here
 use hir::db::AstDatabase;
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     ast::{self, ArgListOwner},
     match_ast, AstNode, SyntaxNode,
 };
-
 use test_utils::tested_by;
 
-use crate::{
-    db::RootDatabase, expand::descend_into_macros, CallInfo, FilePosition, FunctionSignature,
-};
+use crate::{expand::descend_into_macros, CallInfo, FilePosition, FunctionSignature};
 
 /// Computes parameter information for the given call expression.
 pub(crate) fn call_info(db: &RootDatabase, position: FilePosition) -> Option<CallInfo> {
diff --git a/crates/ra_ide/src/completion.rs b/crates/ra_ide/src/completion.rs
index abe1f36ce..fedc02e14 100644
--- a/crates/ra_ide/src/completion.rs
+++ b/crates/ra_ide/src/completion.rs
@@ -17,6 +17,7 @@ mod complete_postfix;
 mod complete_macro_in_item_position;
 
 use ra_db::SourceDatabase;
+use ra_ide_db::RootDatabase;
 
 #[cfg(test)]
 use crate::completion::completion_item::do_completion;
@@ -25,7 +26,7 @@ use crate::{
         completion_context::CompletionContext,
         completion_item::{CompletionKind, Completions},
     },
-    db, FilePosition,
+    FilePosition,
 };
 
 pub use crate::completion::completion_item::{
@@ -54,7 +55,7 @@ pub use crate::completion::completion_item::{
 /// `foo` *should* be present among the completion variants. Filtering by
 /// identifier prefix/fuzzy match should be done higher in the stack, together
 /// with ordering of completions (currently this is done by the client).
-pub(crate) fn completions(db: &db::RootDatabase, position: FilePosition) -> Option<Completions> {
+pub(crate) fn completions(db: &RootDatabase, position: FilePosition) -> Option<Completions> {
     let original_parse = db.parse(position.file_id);
     let ctx = CompletionContext::new(db, &original_parse, position)?;
 
diff --git a/crates/ra_ide/src/completion/completion_context.rs b/crates/ra_ide/src/completion/completion_context.rs
index deaacda6c..5a0407fd7 100644
--- a/crates/ra_ide/src/completion/completion_context.rs
+++ b/crates/ra_ide/src/completion/completion_context.rs
@@ -1,5 +1,6 @@
 //! FIXME: write short doc here
 
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     algo::{find_covering_element, find_node_at_offset},
     ast, AstNode, Parse, SourceFile,
@@ -8,13 +9,13 @@ use ra_syntax::{
 };
 use ra_text_edit::AtomTextEdit;
 
-use crate::{db, FilePosition};
+use crate::FilePosition;
 
 /// `CompletionContext` is created early during completion to figure out, where
 /// exactly is the cursor, syntax-wise.
 #[derive(Debug)]
 pub(crate) struct CompletionContext<'a> {
-    pub(super) db: &'a db::RootDatabase,
+    pub(super) db: &'a RootDatabase,
     pub(super) analyzer: hir::SourceAnalyzer,
     pub(super) offset: TextUnit,
     pub(super) token: SyntaxToken,
@@ -48,7 +49,7 @@ pub(crate) struct CompletionContext<'a> {
 
 impl<'a> CompletionContext<'a> {
     pub(super) fn new(
-        db: &'a db::RootDatabase,
+        db: &'a RootDatabase,
         original_parse: &'a Parse<ast::SourceFile>,
         position: FilePosition,
     ) -> Option<CompletionContext<'a>> {
diff --git a/crates/ra_ide/src/diagnostics.rs b/crates/ra_ide/src/diagnostics.rs
index f403b3bcf..22bd49723 100644
--- a/crates/ra_ide/src/diagnostics.rs
+++ b/crates/ra_ide/src/diagnostics.rs
@@ -5,6 +5,7 @@ use std::cell::RefCell;
 use hir::diagnostics::{AstDiagnostic, Diagnostic as _, DiagnosticSink};
 use itertools::Itertools;
 use ra_db::{RelativePath, SourceDatabase, SourceDatabaseExt};
+use ra_ide_db::RootDatabase;
 use ra_prof::profile;
 use ra_syntax::{
     algo,
@@ -13,7 +14,7 @@ use ra_syntax::{
 };
 use ra_text_edit::{TextEdit, TextEditBuilder};
 
-use crate::{db::RootDatabase, Diagnostic, FileId, FileSystemEdit, SourceChange, SourceFileEdit};
+use crate::{Diagnostic, FileId, FileSystemEdit, SourceChange, SourceFileEdit};
 
 #[derive(Debug, Copy, Clone)]
 pub enum Severity {
diff --git a/crates/ra_ide/src/display/function_signature.rs b/crates/ra_ide/src/display/function_signature.rs
index 1e4a472b4..c23e08e9a 100644
--- a/crates/ra_ide/src/display/function_signature.rs
+++ b/crates/ra_ide/src/display/function_signature.rs
@@ -4,13 +4,11 @@ use std::fmt::{self, Display};
 
 use hir::{Docs, Documentation, HasSource, HirDisplay};
 use join_to_string::join;
+use ra_ide_db::RootDatabase;
 use ra_syntax::ast::{self, AstNode, NameOwner, VisibilityOwner};
 use std::convert::From;
 
-use crate::{
-    db,
-    display::{generic_parameters, where_predicates},
-};
+use crate::display::{generic_parameters, where_predicates};
 
 #[derive(Debug)]
 pub enum CallableKind {
@@ -48,13 +46,13 @@ impl FunctionSignature {
         self
     }
 
-    pub(crate) fn from_hir(db: &db::RootDatabase, function: hir::Function) -> Self {
+    pub(crate) fn from_hir(db: &RootDatabase, function: hir::Function) -> Self {
         let doc = function.docs(db);
         let ast_node = function.source(db).value;
         FunctionSignature::from(&ast_node).with_doc_opt(doc)
     }
 
-    pub(crate) fn from_struct(db: &db::RootDatabase, st: hir::Struct) -> Option<Self> {
+    pub(crate) fn from_struct(db: &RootDatabase, st: hir::Struct) -> Option<Self> {
         let node: ast::StructDef = st.source(db).value;
         match node.kind() {
             ast::StructKind::Record(_) => return None,
@@ -86,10 +84,7 @@ impl FunctionSignature {
         )
     }
 
-    pub(crate) fn from_enum_variant(
-        db: &db::RootDatabase,
-        variant: hir::EnumVariant,
-    ) -> Option<Self> {
+    pub(crate) fn from_enum_variant(db: &RootDatabase, variant: hir::EnumVariant) -> Option<Self> {
         let node: ast::EnumVariant = variant.source(db).value;
         match node.kind() {
             ast::StructKind::Record(_) | ast::StructKind::Unit => return None,
@@ -126,7 +121,7 @@ impl FunctionSignature {
         )
     }
 
-    pub(crate) fn from_macro(db: &db::RootDatabase, macro_def: hir::MacroDef) -> Option<Self> {
+    pub(crate) fn from_macro(db: &RootDatabase, macro_def: hir::MacroDef) -> Option<Self> {
         let node: ast::MacroCall = macro_def.source(db).value;
 
         let params = vec![];
diff --git a/crates/ra_ide/src/display/navigation_target.rs b/crates/ra_ide/src/display/navigation_target.rs
index b2af3479c..906aab1eb 100644
--- a/crates/ra_ide/src/display/navigation_target.rs
+++ b/crates/ra_ide/src/display/navigation_target.rs
@@ -3,6 +3,7 @@
 use either::Either;
 use hir::{AssocItem, FieldSource, HasSource, InFile, ModuleSource};
 use ra_db::{FileId, SourceDatabase};
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     ast::{self, DocCommentsOwner, NameOwner},
     match_ast, AstNode, SmolStr,
@@ -10,7 +11,7 @@ use ra_syntax::{
     TextRange,
 };
 
-use crate::{db::RootDatabase, expand::original_range, FileSymbol};
+use crate::{expand::original_range, FileSymbol};
 
 use super::short_label::ShortLabel;
 
diff --git a/crates/ra_ide/src/expand.rs b/crates/ra_ide/src/expand.rs
index 831438c09..9f3aaa3a3 100644
--- a/crates/ra_ide/src/expand.rs
+++ b/crates/ra_ide/src/expand.rs
@@ -3,9 +3,10 @@ use std::iter::successors;
 
 use hir::{InFile, Origin};
 use ra_db::FileId;
+use ra_ide_db::RootDatabase;
 use ra_syntax::{ast, AstNode, SyntaxNode, SyntaxToken, TextRange};
 
-use crate::{db::RootDatabase, FileRange};
+use crate::FileRange;
 
 pub(crate) fn original_range(db: &RootDatabase, node: InFile<&SyntaxNode>) -> FileRange {
     if let Some((range, Origin::Call)) = original_range_and_origin(db, node) {
diff --git a/crates/ra_ide/src/expand_macro.rs b/crates/ra_ide/src/expand_macro.rs
index 0f7b6e875..af2783bef 100644
--- a/crates/ra_ide/src/expand_macro.rs
+++ b/crates/ra_ide/src/expand_macro.rs
@@ -1,14 +1,15 @@
 //! This modules implements "expand macro" functionality in the IDE
 
-use crate::{db::RootDatabase, FilePosition};
 use hir::db::AstDatabase;
 use ra_db::SourceDatabase;
-use rustc_hash::FxHashMap;
-
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     algo::{find_node_at_offset, replace_descendants},
     ast, AstNode, NodeOrToken, SyntaxElement, SyntaxKind, SyntaxNode, WalkEvent, T,
 };
+use rustc_hash::FxHashMap;
+
+use crate::FilePosition;
 
 pub struct ExpandedMacro {
     pub name: String,
@@ -185,7 +186,7 @@ fn some_thing() -> u32 {
         //- /lib.rs
         macro_rules! match_ast {
             (match $node:ident { $($tt:tt)* }) => { match_ast!(match ($node) { $($tt)* }) };
-        
+
             (match ($node:expr) {
                 $( ast::$ast:ident($it:ident) => $res:block, )*
                 _ => $catch_all:expr $(,)?
@@ -193,7 +194,7 @@ fn some_thing() -> u32 {
                 $( if let Some($it) = ast::$ast::cast($node.clone()) $res else )*
                 { $catch_all }
             }};
-        }        
+        }
 
         fn main() {
             mat<|>ch_ast! {
@@ -227,11 +228,11 @@ fn some_thing() -> u32 {
             r#"
         //- /lib.rs
         macro_rules! match_ast {
-            (match $node:ident { $($tt:tt)* }) => { match_ast!(match ($node) { $($tt)* }) };        
+            (match $node:ident { $($tt:tt)* }) => { match_ast!(match ($node) { $($tt)* }) };
             (match ($node:expr) {}) => {{}};
-        }        
+        }
 
-        fn main() {        
+        fn main() {
             let p = f(|it| {
                 let res = mat<|>ch_ast! { match c {}};
                 Some(res)
@@ -254,9 +255,9 @@ fn some_thing() -> u32 {
         }
         macro_rules! foo {
             () => {bar!()};
-        }        
+        }
 
-        fn main() {        
+        fn main() {
             let res = fo<|>o!();
         }
         "#,
@@ -277,9 +278,9 @@ fn some_thing() -> u32 {
         }
         macro_rules! foo {
             () => {$crate::bar!()};
-        }        
+        }
 
-        fn main() {        
+        fn main() {
             let res = fo<|>o!();
         }
         "#,
diff --git a/crates/ra_ide/src/extend_selection.rs b/crates/ra_ide/src/extend_selection.rs
index 930e0c4c2..726963a33 100644
--- a/crates/ra_ide/src/extend_selection.rs
+++ b/crates/ra_ide/src/extend_selection.rs
@@ -1,6 +1,10 @@
 //! FIXME: write short doc here
 
+use std::iter::successors;
+
+use hir::db::AstDatabase;
 use ra_db::SourceDatabase;
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     algo::find_covering_element,
     ast::{self, AstNode, AstToken},
@@ -9,9 +13,7 @@ use ra_syntax::{
     SyntaxNode, SyntaxToken, TextRange, TextUnit, TokenAtOffset, T,
 };
 
-use crate::{db::RootDatabase, expand::descend_into_macros, FileId, FileRange};
-use hir::db::AstDatabase;
-use std::iter::successors;
+use crate::{expand::descend_into_macros, FileId, FileRange};
 
 pub(crate) fn extend_selection(db: &RootDatabase, frange: FileRange) -> TextRange {
     let src = db.parse(frange.file_id).tree();
@@ -512,8 +514,8 @@ fn bar(){}
     fn test_extend_trait_bounds_list_in_where_clause() {
         do_check(
             r#"
-fn foo<R>() 
-    where 
+fn foo<R>()
+    where
         R: req::Request + 'static,
         R::Params: DeserializeOwned<|> + panic::UnwindSafe + 'static,
         R::Result: Serialize + 'static,
diff --git a/crates/ra_ide/src/goto_definition.rs b/crates/ra_ide/src/goto_definition.rs
index 5a12a619c..e9329a72c 100644
--- a/crates/ra_ide/src/goto_definition.rs
+++ b/crates/ra_ide/src/goto_definition.rs
@@ -1,6 +1,7 @@
 //! FIXME: write short doc here
 
 use hir::{db::AstDatabase, InFile, SourceBinder};
+use ra_ide_db::{symbol_index, RootDatabase};
 use ra_syntax::{
     ast::{self, DocCommentsOwner},
     match_ast, AstNode,
@@ -9,7 +10,6 @@ use ra_syntax::{
 };
 
 use crate::{
-    db::RootDatabase,
     display::{ShortLabel, ToNav},
     expand::descend_into_macros,
     references::{classify_name_ref, NameKind::*},
@@ -94,7 +94,7 @@ pub(crate) fn reference_definition(
     };
 
     // Fallback index based approach:
-    let navs = crate::symbol_index::index_resolve(sb.db, name_ref.value)
+    let navs = symbol_index::index_resolve(sb.db, name_ref.value)
         .into_iter()
         .map(|s| s.to_nav(sb.db))
         .collect();
diff --git a/crates/ra_ide/src/goto_type_definition.rs b/crates/ra_ide/src/goto_type_definition.rs
index ce8b6c72a..11ad6d137 100644
--- a/crates/ra_ide/src/goto_type_definition.rs
+++ b/crates/ra_ide/src/goto_type_definition.rs
@@ -1,11 +1,11 @@
 //! FIXME: write short doc here
 
 use hir::db::AstDatabase;
+use ra_ide_db::RootDatabase;
 use ra_syntax::{ast, AstNode, SyntaxKind::*, SyntaxToken, TokenAtOffset};
 
 use crate::{
-    db::RootDatabase, display::ToNav, expand::descend_into_macros, FilePosition, NavigationTarget,
-    RangeInfo,
+    display::ToNav, expand::descend_into_macros, FilePosition, NavigationTarget, RangeInfo,
 };
 
 pub(crate) fn goto_type_definition(
diff --git a/crates/ra_ide/src/hover.rs b/crates/ra_ide/src/hover.rs
index 6661e5cb2..315b88190 100644
--- a/crates/ra_ide/src/hover.rs
+++ b/crates/ra_ide/src/hover.rs
@@ -2,6 +2,7 @@
 
 use hir::{db::AstDatabase, Adt, HasSource, HirDisplay, SourceBinder};
 use ra_db::SourceDatabase;
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     algo::find_covering_element,
     ast::{self, DocCommentsOwner},
@@ -11,7 +12,6 @@ use ra_syntax::{
 };
 
 use crate::{
-    db::RootDatabase,
     display::{macro_label, rust_code_markup, rust_code_markup_with_doc, ShortLabel},
     expand::descend_into_macros,
     references::{classify_name, classify_name_ref, NameKind, NameKind::*},
diff --git a/crates/ra_ide/src/impls.rs b/crates/ra_ide/src/impls.rs
index 9834025d3..64a2dadc8 100644
--- a/crates/ra_ide/src/impls.rs
+++ b/crates/ra_ide/src/impls.rs
@@ -2,9 +2,10 @@
 
 use hir::{Crate, ImplBlock, SourceBinder};
 use ra_db::SourceDatabase;
+use ra_ide_db::RootDatabase;
 use ra_syntax::{algo::find_node_at_offset, ast, AstNode};
 
-use crate::{db::RootDatabase, display::ToNav, FilePosition, NavigationTarget, RangeInfo};
+use crate::{display::ToNav, FilePosition, NavigationTarget, RangeInfo};
 
 pub(crate) fn goto_implementation(
     db: &RootDatabase,
diff --git a/crates/ra_ide/src/imports_locator.rs b/crates/ra_ide/src/imports_locator.rs
index 9e1a1c1ec..cfd58aafe 100644
--- a/crates/ra_ide/src/imports_locator.rs
+++ b/crates/ra_ide/src/imports_locator.rs
@@ -1,17 +1,20 @@
 //! This module contains an import search funcionality that is provided to the ra_assists module.
 //! Later, this should be moved away to a separate crate that is accessible from the ra_assists module.
 
-use crate::{
-    db::RootDatabase,
-    references::{classify_name, NameDefinition, NameKind},
-    symbol_index::{self, FileSymbol},
-    Query,
-};
 use hir::{db::HirDatabase, ModuleDef, SourceBinder};
 use ra_assists::ImportsLocator;
+use ra_ide_db::{
+    symbol_index::{self, FileSymbol},
+    RootDatabase,
+};
 use ra_prof::profile;
 use ra_syntax::{ast, AstNode, SyntaxKind::NAME};
 
+use crate::{
+    references::{classify_name, NameDefinition, NameKind},
+    Query,
+};
+
 pub(crate) struct ImportsLocatorIde<'a> {
     source_binder: SourceBinder<'a, RootDatabase>,
 }
diff --git a/crates/ra_ide/src/inlay_hints.rs b/crates/ra_ide/src/inlay_hints.rs
index de447a5aa..6b0d3d996 100644
--- a/crates/ra_ide/src/inlay_hints.rs
+++ b/crates/ra_ide/src/inlay_hints.rs
@@ -2,13 +2,14 @@
 
 use hir::{HirDisplay, SourceAnalyzer, SourceBinder};
 use once_cell::unsync::Lazy;
+use ra_ide_db::RootDatabase;
 use ra_prof::profile;
 use ra_syntax::{
     ast::{self, ArgListOwner, AstNode, TypeAscriptionOwner},
     match_ast, SmolStr, SourceFile, SyntaxKind, SyntaxNode, TextRange,
 };
 
-use crate::{db::RootDatabase, FileId, FunctionSignature};
+use crate::{FileId, FunctionSignature};
 
 #[derive(Debug, PartialEq, Eq)]
 pub enum InlayKind {
diff --git a/crates/ra_ide/src/lib.rs b/crates/ra_ide/src/lib.rs
index 03ad6b2c1..5fb111a90 100644
--- a/crates/ra_ide/src/lib.rs
+++ b/crates/ra_ide/src/lib.rs
@@ -10,12 +10,8 @@
 // For proving that RootDatabase is RefUnwindSafe.
 #![recursion_limit = "128"]
 
-mod db;
 pub mod mock_analysis;
-mod symbol_index;
-mod change;
 mod source_change;
-mod feature_flags;
 
 mod status;
 mod completion;
@@ -35,14 +31,11 @@ mod assists;
 mod diagnostics;
 mod syntax_tree;
 mod folding_ranges;
-mod line_index;
-mod line_index_utils;
 mod join_lines;
 mod typing;
 mod matching_brace;
 mod display;
 mod inlay_hints;
-mod wasm_shims;
 mod expand;
 mod expand_macro;
 
@@ -58,24 +51,24 @@ use ra_db::{
     salsa::{self, ParallelDatabase},
     CheckCanceled, Env, FileLoader, SourceDatabase,
 };
+use ra_ide_db::{
+    symbol_index::{self, FileSymbol},
+    LineIndexDatabase,
+};
 use ra_syntax::{SourceFile, TextRange, TextUnit};
 
-use crate::{db::LineIndexDatabase, display::ToNav, symbol_index::FileSymbol};
+use crate::display::ToNav;
 
 pub use crate::{
     assists::{Assist, AssistId},
     call_hierarchy::CallItem,
-    change::{AnalysisChange, LibraryData},
     completion::{CompletionItem, CompletionItemKind, InsertTextFormat},
     diagnostics::Severity,
     display::{file_structure, FunctionSignature, NavigationTarget, StructureNode},
     expand_macro::ExpandedMacro,
-    feature_flags::FeatureFlags,
     folding_ranges::{Fold, FoldKind},
     hover::HoverResult,
     inlay_hints::{InlayHint, InlayKind},
-    line_index::{LineCol, LineIndex},
-    line_index_utils::translate_offset_with_edit,
     references::{
         Declaration, Reference, ReferenceAccess, ReferenceKind, ReferenceSearchResult, SearchScope,
     },
@@ -88,6 +81,14 @@ pub use hir::Documentation;
 pub use ra_db::{
     Canceled, CrateGraph, CrateId, Edition, FileId, FilePosition, FileRange, SourceRootId,
 };
+pub use ra_ide_db::{
+    change::{AnalysisChange, LibraryData},
+    feature_flags::FeatureFlags,
+    line_index::{LineCol, LineIndex},
+    line_index_utils::translate_offset_with_edit,
+    symbol_index::Query,
+    RootDatabase,
+};
 
 pub type Cancelable<T> = Result<T, Canceled>;
 
@@ -99,46 +100,6 @@ pub struct Diagnostic {
     pub severity: Severity,
 }
 
-#[derive(Debug)]
-pub struct Query {
-    query: String,
-    lowercased: String,
-    only_types: bool,
-    libs: bool,
-    exact: bool,
-    limit: usize,
-}
-
-impl Query {
-    pub fn new(query: String) -> Query {
-        let lowercased = query.to_lowercase();
-        Query {
-            query,
-            lowercased,
-            only_types: false,
-            libs: false,
-            exact: false,
-            limit: usize::max_value(),
-        }
-    }
-
-    pub fn only_types(&mut self) {
-        self.only_types = true;
-    }
-
-    pub fn libs(&mut self) {
-        self.libs = true;
-    }
-
-    pub fn exact(&mut self) {
-        self.exact = true;
-    }
-
-    pub fn limit(&mut self, limit: usize) {
-        self.limit = limit
-    }
-}
-
 /// Info associated with a text range.
 #[derive(Debug)]
 pub struct RangeInfo<T> {
@@ -163,7 +124,7 @@ pub struct CallInfo {
 /// `AnalysisHost` stores the current state of the world.
 #[derive(Debug)]
 pub struct AnalysisHost {
-    db: db::RootDatabase,
+    db: RootDatabase,
 }
 
 impl Default for AnalysisHost {
@@ -174,7 +135,7 @@ impl Default for AnalysisHost {
 
 impl AnalysisHost {
     pub fn new(lru_capcity: Option<usize>, feature_flags: FeatureFlags) -> AnalysisHost {
-        AnalysisHost { db: db::RootDatabase::new(lru_capcity, feature_flags) }
+        AnalysisHost { db: RootDatabase::new(lru_capcity, feature_flags) }
     }
     /// Returns a snapshot of the current state, which you can query for
     /// semantic information.
@@ -224,7 +185,7 @@ impl AnalysisHost {
 /// `Analysis` are canceled (most method return `Err(Canceled)`).
 #[derive(Debug)]
 pub struct Analysis {
-    db: salsa::Snapshot<db::RootDatabase>,
+    db: salsa::Snapshot<RootDatabase>,
 }
 
 // As a general design guideline, `Analysis` API are intended to be independent
@@ -505,7 +466,7 @@ impl Analysis {
     }
 
     /// Performs an operation on that may be Canceled.
-    fn with_db<F: FnOnce(&db::RootDatabase) -> T + std::panic::UnwindSafe, T>(
+    fn with_db<F: FnOnce(&RootDatabase) -> T + std::panic::UnwindSafe, T>(
         &self,
         f: F,
     ) -> Cancelable<T> {
@@ -518,3 +479,77 @@ fn analysis_is_send() {
     fn is_send<T: Send>() {}
     is_send::<Analysis>();
 }
+
+#[cfg(test)]
+mod tests {
+    use crate::{display::NavigationTarget, mock_analysis::single_file, Query};
+    use ra_syntax::{
+        SmolStr,
+        SyntaxKind::{FN_DEF, STRUCT_DEF},
+    };
+
+    #[test]
+    fn test_world_symbols_with_no_container() {
+        let code = r#"
+    enum FooInner { }
+    "#;
+
+        let mut symbols = get_symbols_matching(code, "FooInner");
+
+        let s = symbols.pop().unwrap();
+
+        assert_eq!(s.name(), "FooInner");
+        assert!(s.container_name().is_none());
+    }
+
+    #[test]
+    fn test_world_symbols_include_container_name() {
+        let code = r#"
+fn foo() {
+    enum FooInner { }
+}
+    "#;
+
+        let mut symbols = get_symbols_matching(code, "FooInner");
+
+        let s = symbols.pop().unwrap();
+
+        assert_eq!(s.name(), "FooInner");
+        assert_eq!(s.container_name(), Some(&SmolStr::new("foo")));
+
+        let code = r#"
+mod foo {
+    struct FooInner;
+}
+    "#;
+
+        let mut symbols = get_symbols_matching(code, "FooInner");
+
+        let s = symbols.pop().unwrap();
+
+        assert_eq!(s.name(), "FooInner");
+        assert_eq!(s.container_name(), Some(&SmolStr::new("foo")));
+    }
+
+    #[test]
+    fn test_world_symbols_are_case_sensitive() {
+        let code = r#"
+fn foo() {}
+
+struct Foo;
+        "#;
+
+        let symbols = get_symbols_matching(code, "Foo");
+
+        let fn_match = symbols.iter().find(|s| s.name() == "foo").map(|s| s.kind());
+        let struct_match = symbols.iter().find(|s| s.name() == "Foo").map(|s| s.kind());
+
+        assert_eq!(fn_match, Some(FN_DEF));
+        assert_eq!(struct_match, Some(STRUCT_DEF));
+    }
+
+    fn get_symbols_matching(text: &str, query: &str) -> Vec<NavigationTarget> {
+        let (analysis, _) = single_file(text);
+        analysis.symbol_search(Query::new(query.into())).unwrap()
+    }
+}
diff --git a/crates/ra_ide/src/parent_module.rs b/crates/ra_ide/src/parent_module.rs
index 2dbccfc3b..e0332da88 100644
--- a/crates/ra_ide/src/parent_module.rs
+++ b/crates/ra_ide/src/parent_module.rs
@@ -1,12 +1,13 @@
 //! FIXME: write short doc here
 
 use ra_db::{CrateId, FileId, FilePosition, SourceDatabase};
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     algo::find_node_at_offset,
     ast::{self, AstNode},
 };
 
-use crate::{db::RootDatabase, NavigationTarget};
+use crate::NavigationTarget;
 
 /// This returns `Vec` because a module may be included from several places. We
 /// don't handle this case yet though, so the Vec has length at most one.
diff --git a/crates/ra_ide/src/references.rs b/crates/ra_ide/src/references.rs
index ebded715d..b47f8bcd9 100644
--- a/crates/ra_ide/src/references.rs
+++ b/crates/ra_ide/src/references.rs
@@ -17,6 +17,7 @@ mod search_scope;
 use hir::{InFile, SourceBinder};
 use once_cell::unsync::Lazy;
 use ra_db::{SourceDatabase, SourceDatabaseExt};
+use ra_ide_db::RootDatabase;
 use ra_prof::profile;
 use ra_syntax::{
     algo::find_node_at_offset,
@@ -24,9 +25,7 @@ use ra_syntax::{
     match_ast, AstNode, SourceFile, SyntaxKind, SyntaxNode, TextRange, TextUnit, TokenAtOffset,
 };
 
-use crate::{
-    db::RootDatabase, display::ToNav, FilePosition, FileRange, NavigationTarget, RangeInfo,
-};
+use crate::{display::ToNav, FilePosition, FileRange, NavigationTarget, RangeInfo};
 
 pub(crate) use self::{
     classify::{classify_name, classify_name_ref},
diff --git a/crates/ra_ide/src/references/classify.rs b/crates/ra_ide/src/references/classify.rs
index 46cba30a3..758ea4e8b 100644
--- a/crates/ra_ide/src/references/classify.rs
+++ b/crates/ra_ide/src/references/classify.rs
@@ -9,7 +9,7 @@ use super::{
     name_definition::{from_assoc_item, from_module_def, from_struct_field},
     NameDefinition, NameKind,
 };
-use crate::db::RootDatabase;
+use ra_ide_db::RootDatabase;
 
 pub(crate) fn classify_name(
     sb: &mut SourceBinder<RootDatabase>,
diff --git a/crates/ra_ide/src/references/name_definition.rs b/crates/ra_ide/src/references/name_definition.rs
index 1e4226ab9..71565e6d3 100644
--- a/crates/ra_ide/src/references/name_definition.rs
+++ b/crates/ra_ide/src/references/name_definition.rs
@@ -9,7 +9,7 @@ use hir::{
 };
 use ra_syntax::{ast, ast::VisibilityOwner};
 
-use crate::db::RootDatabase;
+use ra_ide_db::RootDatabase;
 
 #[derive(Debug, PartialEq, Eq)]
 pub enum NameKind {
diff --git a/crates/ra_ide/src/references/rename.rs b/crates/ra_ide/src/references/rename.rs
index 9a84c1c88..08e77c01f 100644
--- a/crates/ra_ide/src/references/rename.rs
+++ b/crates/ra_ide/src/references/rename.rs
@@ -2,14 +2,14 @@
 
 use hir::ModuleSource;
 use ra_db::{RelativePath, RelativePathBuf, SourceDatabase, SourceDatabaseExt};
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     algo::find_node_at_offset, ast, lex_single_valid_syntax_kind, AstNode, SyntaxKind, SyntaxNode,
 };
 use ra_text_edit::TextEdit;
 
 use crate::{
-    db::RootDatabase, FileId, FilePosition, FileSystemEdit, RangeInfo, SourceChange,
-    SourceFileEdit, TextRange,
+    FileId, FilePosition, FileSystemEdit, RangeInfo, SourceChange, SourceFileEdit, TextRange,
 };
 
 use super::find_all_refs;
diff --git a/crates/ra_ide/src/references/search_scope.rs b/crates/ra_ide/src/references/search_scope.rs
index f8211a746..97c65c2cd 100644
--- a/crates/ra_ide/src/references/search_scope.rs
+++ b/crates/ra_ide/src/references/search_scope.rs
@@ -10,7 +10,7 @@ use ra_prof::profile;
 use ra_syntax::{AstNode, TextRange};
 use rustc_hash::FxHashMap;
 
-use crate::db::RootDatabase;
+use ra_ide_db::RootDatabase;
 
 use super::{NameDefinition, NameKind};
 
diff --git a/crates/ra_ide/src/runnables.rs b/crates/ra_ide/src/runnables.rs
index 8622dd956..b6b0c70f9 100644
--- a/crates/ra_ide/src/runnables.rs
+++ b/crates/ra_ide/src/runnables.rs
@@ -3,12 +3,13 @@
 use hir::InFile;
 use itertools::Itertools;
 use ra_db::SourceDatabase;
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     ast::{self, AstNode, AttrsOwner, ModuleItemOwner, NameOwner},
     match_ast, SyntaxNode, TextRange,
 };
 
-use crate::{db::RootDatabase, FileId};
+use crate::FileId;
 
 #[derive(Debug)]
 pub struct Runnable {
diff --git a/crates/ra_ide/src/status.rs b/crates/ra_ide/src/status.rs
index 1bb27eb85..30eb5c995 100644
--- a/crates/ra_ide/src/status.rs
+++ b/crates/ra_ide/src/status.rs
@@ -10,14 +10,14 @@ use ra_db::{
     },
     FileTextQuery, SourceRootId,
 };
+use ra_ide_db::{
+    symbol_index::{LibrarySymbolsQuery, SymbolIndex},
+    RootDatabase,
+};
 use ra_prof::{memory_usage, Bytes};
 use ra_syntax::{ast, Parse, SyntaxNode};
 
-use crate::{
-    db::RootDatabase,
-    symbol_index::{LibrarySymbolsQuery, SymbolIndex},
-    FileId,
-};
+use crate::FileId;
 
 fn syntax_tree_stats(db: &RootDatabase) -> SyntaxTreeStats {
     db.query(ra_db::ParseQuery).entries::<SyntaxTreeStats>()
diff --git a/crates/ra_ide/src/syntax_highlighting.rs b/crates/ra_ide/src/syntax_highlighting.rs
index 530b984fc..c5d249fe8 100644
--- a/crates/ra_ide/src/syntax_highlighting.rs
+++ b/crates/ra_ide/src/syntax_highlighting.rs
@@ -4,6 +4,7 @@ use rustc_hash::FxHashMap;
 
 use hir::{HirFileId, InFile, Name, SourceAnalyzer, SourceBinder};
 use ra_db::SourceDatabase;
+use ra_ide_db::RootDatabase;
 use ra_prof::profile;
 use ra_syntax::{
     ast, AstNode, Direction, SyntaxElement, SyntaxKind, SyntaxKind::*, SyntaxToken, TextRange,
@@ -11,7 +12,6 @@ use ra_syntax::{
 };
 
 use crate::{
-    db::RootDatabase,
     expand::descend_into_macros_with_analyzer,
     references::{
         classify_name, classify_name_ref,
diff --git a/crates/ra_ide/src/syntax_tree.rs b/crates/ra_ide/src/syntax_tree.rs
index 4d0f0fc47..55966daf3 100644
--- a/crates/ra_ide/src/syntax_tree.rs
+++ b/crates/ra_ide/src/syntax_tree.rs
@@ -1,7 +1,7 @@
 //! FIXME: write short doc here
 
-use crate::db::RootDatabase;
 use ra_db::SourceDatabase;
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     algo, AstNode, NodeOrToken, SourceFile,
     SyntaxKind::{RAW_STRING, STRING},
diff --git a/crates/ra_ide/src/typing.rs b/crates/ra_ide/src/typing.rs
index 21e5be9b3..e5d1779fd 100644
--- a/crates/ra_ide/src/typing.rs
+++ b/crates/ra_ide/src/typing.rs
@@ -15,6 +15,7 @@
 
 use ra_db::{FilePosition, SourceDatabase};
 use ra_fmt::leading_indent;
+use ra_ide_db::RootDatabase;
 use ra_syntax::{
     algo::find_node_at_offset,
     ast::{self, AstToken},
@@ -24,7 +25,7 @@ use ra_syntax::{
 };
 use ra_text_edit::TextEdit;
 
-use crate::{db::RootDatabase, source_change::SingleFileChange, SourceChange, SourceFileEdit};
+use crate::{source_change::SingleFileChange, SourceChange, SourceFileEdit};
 
 pub(crate) fn on_enter(db: &RootDatabase, position: FilePosition) -> Option<SourceChange> {
     let parse = db.parse(position.file_id);
diff --git a/crates/ra_ide_db/Cargo.toml b/crates/ra_ide_db/Cargo.toml
new file mode 100644
index 000000000..1b7905eb3
--- /dev/null
+++ b/crates/ra_ide_db/Cargo.toml
@@ -0,0 +1,48 @@
+[package]
+edition = "2018"
+name = "ra_ide_db"
+version = "0.1.0"
+authors = ["rust-analyzer developers"]
+
+[lib]
+doctest = false
+
+[features]
+wasm = []
+
+[dependencies]
+either = "1.5"
+format-buf = "1.0.0"
+indexmap = "1.3.0"
+itertools = "0.8.0"
+join_to_string = "0.1.3"
+log = "0.4.5"
+rayon = "1.0.2"
+fst = { version = "0.3.1", default-features = false }
+rustc-hash = "1.0"
+unicase = "2.2.0"
+superslice = "1.0.0"
+rand = { version = "0.7.0", features = ["small_rng"] }
+once_cell = "1.2.0"
+
+ra_syntax = { path = "../ra_syntax" }
+ra_text_edit = { path = "../ra_text_edit" }
+ra_db = { path = "../ra_db" }
+ra_cfg = { path = "../ra_cfg" }
+ra_fmt = { path = "../ra_fmt" }
+ra_prof = { path = "../ra_prof" }
+test_utils = { path = "../test_utils" }
+ra_assists = { path = "../ra_assists" }
+
+# ra_ide should depend only on the top-level `hir` package. if you need
+# something from some `hir_xxx` subpackage, reexport the API via `hir`.
+hir = { path = "../ra_hir", package = "ra_hir" }
+
+[dev-dependencies]
+insta = "0.13.0"
+
+[dev-dependencies.proptest]
+version = "0.9.0"
+# Disable `fork` feature to allow compiling on webassembly
+default-features = false
+features = ["std", "bit-set", "break-dead-code"]
diff --git a/crates/ra_ide/src/change.rs b/crates/ra_ide_db/src/change.rs
index 18dad2ea3..4668784d3 100644
--- a/crates/ra_ide/src/change.rs
+++ b/crates/ra_ide_db/src/change.rs
@@ -1,4 +1,5 @@
-//! FIXME: write short doc here
+//! Defines a unit of change that can applied to a state of IDE to get the next
+//! state. Changes are transactional.
 
 use std::{fmt, sync::Arc, time};
 
@@ -14,8 +15,8 @@ use rayon::prelude::*;
 use rustc_hash::FxHashMap;
 
 use crate::{
-    db::{DebugData, RootDatabase},
     symbol_index::{SymbolIndex, SymbolsDatabase},
+    DebugData, RootDatabase,
 };
 
 #[derive(Default)]
@@ -168,12 +169,12 @@ impl LibraryData {
 const GC_COOLDOWN: time::Duration = time::Duration::from_millis(100);
 
 impl RootDatabase {
-    pub(crate) fn request_cancellation(&mut self) {
+    pub fn request_cancellation(&mut self) {
         let _p = profile("RootDatabase::request_cancellation");
         self.salsa_runtime_mut().synthetic_write(Durability::LOW);
     }
 
-    pub(crate) fn apply_change(&mut self, change: AnalysisChange) {
+    pub fn apply_change(&mut self, change: AnalysisChange) {
         let _p = profile("RootDatabase::apply_change");
         self.request_cancellation();
         log::info!("apply_change {:?}", change);
@@ -245,7 +246,7 @@ impl RootDatabase {
         self.set_source_root_with_durability(root_id, Arc::new(source_root), durability);
     }
 
-    pub(crate) fn maybe_collect_garbage(&mut self) {
+    pub fn maybe_collect_garbage(&mut self) {
         if cfg!(feature = "wasm") {
             return;
         }
@@ -255,7 +256,7 @@ impl RootDatabase {
         }
     }
 
-    pub(crate) fn collect_garbage(&mut self) {
+    pub fn collect_garbage(&mut self) {
         if cfg!(feature = "wasm") {
             return;
         }
@@ -282,7 +283,7 @@ impl RootDatabase {
         self.query(hir::db::BodyQuery).sweep(sweep);
     }
 
-    pub(crate) fn per_query_memory_usage(&mut self) -> Vec<(String, Bytes)> {
+    pub fn per_query_memory_usage(&mut self) -> Vec<(String, Bytes)> {
         let mut acc: Vec<(String, Bytes)> = vec![];
         let sweep = SweepStrategy::default().discard_values().sweep_all_revisions();
         macro_rules! sweep_each_query {
diff --git a/crates/ra_ide/src/feature_flags.rs b/crates/ra_ide_db/src/feature_flags.rs
index 85617640d..1b3cabf4d 100644
--- a/crates/ra_ide/src/feature_flags.rs
+++ b/crates/ra_ide_db/src/feature_flags.rs
@@ -1,4 +1,4 @@
-//! FIXME: write short doc here
+//! See docs for `FeatureFlags`.
 
 use rustc_hash::FxHashMap;
 
diff --git a/crates/ra_ide/src/db.rs b/crates/ra_ide_db/src/lib.rs
index 47d0aed6f..e922d1e5f 100644
--- a/crates/ra_ide/src/db.rs
+++ b/crates/ra_ide_db/src/lib.rs
@@ -1,4 +1,13 @@
-//! FIXME: write short doc here
+//! This crate defines the core datastructure representing IDE state -- `RootDatabase`.
+//!
+//! It is mainly a `HirDatabase` for semantic analysis, plus a `SymbolsDatabase`, for fuzzy search.
+
+pub mod line_index;
+pub mod line_index_utils;
+pub mod feature_flags;
+pub mod symbol_index;
+pub mod change;
+mod wasm_shims;
 
 use std::sync::Arc;
 
@@ -9,10 +18,7 @@ use ra_db::{
 };
 use rustc_hash::FxHashMap;
 
-use crate::{
-    symbol_index::{self, SymbolsDatabase},
-    FeatureFlags, LineIndex,
-};
+use crate::{feature_flags::FeatureFlags, line_index::LineIndex, symbol_index::SymbolsDatabase};
 
 #[salsa::database(
     ra_db::SourceDatabaseStorage,
@@ -25,12 +31,12 @@ use crate::{
     hir::db::HirDatabaseStorage
 )]
 #[derive(Debug)]
-pub(crate) struct RootDatabase {
+pub struct RootDatabase {
     runtime: salsa::Runtime<RootDatabase>,
-    pub(crate) feature_flags: Arc<FeatureFlags>,
+    pub feature_flags: Arc<FeatureFlags>,
     pub(crate) debug_data: Arc<DebugData>,
-    pub(crate) last_gc: crate::wasm_shims::Instant,
-    pub(crate) last_gc_check: crate::wasm_shims::Instant,
+    pub last_gc: crate::wasm_shims::Instant,
+    pub last_gc_check: crate::wasm_shims::Instant,
 }
 
 impl FileLoader for RootDatabase {
@@ -109,7 +115,7 @@ impl salsa::ParallelDatabase for RootDatabase {
 }
 
 #[salsa::query_group(LineIndexDatabaseStorage)]
-pub(crate) trait LineIndexDatabase: ra_db::SourceDatabase + CheckCanceled {
+pub trait LineIndexDatabase: ra_db::SourceDatabase + CheckCanceled {
     fn line_index(&self, file_id: FileId) -> Arc<LineIndex>;
 }
 
diff --git a/crates/ra_ide/src/line_index.rs b/crates/ra_ide_db/src/line_index.rs
index 710890d27..452c87ac5 100644
--- a/crates/ra_ide/src/line_index.rs
+++ b/crates/ra_ide_db/src/line_index.rs
@@ -1,6 +1,7 @@
-//! FIXME: write short doc here
+//! `LineIndex` maps flat `TextUnit` offsets into `(Line, Column)`
+//! representation.
 
-use crate::TextUnit;
+use ra_syntax::TextUnit;
 use rustc_hash::FxHashMap;
 use superslice::Ext;
 
diff --git a/crates/ra_ide/src/line_index_utils.rs b/crates/ra_ide_db/src/line_index_utils.rs
index bd1e08feb..435b06511 100644
--- a/crates/ra_ide/src/line_index_utils.rs
+++ b/crates/ra_ide_db/src/line_index_utils.rs
@@ -1,9 +1,87 @@
-//! FIXME: write short doc here
+//! Code actions can specify desirable final position of the cursor.
+//!
+//! The position is specified as a `TextUnit` in the final file. We need to send
+//! it in `(Line, Column)` coordinate though. However, we only have a LineIndex
+//! for a file pre-edit!
+//!
+//! Code in this module applies this "to (Line, Column) after edit"
+//! transformation.
 
-use crate::{line_index::Utf16Char, LineCol, LineIndex};
 use ra_syntax::{TextRange, TextUnit};
 use ra_text_edit::{AtomTextEdit, TextEdit};
 
+use crate::line_index::{LineCol, LineIndex, Utf16Char};
+
+pub fn translate_offset_with_edit(
+    line_index: &LineIndex,
+    offset: TextUnit,
+    text_edit: &TextEdit,
+) -> LineCol {
+    let mut state = Edits::from_text_edit(&text_edit);
+
+    let mut res = RunningLineCol::new();
+
+    macro_rules! test_step {
+        ($x:ident) => {
+            match &$x {
+                Step::Newline(n) => {
+                    if offset < *n {
+                        return res.to_line_col(offset);
+                    } else {
+                        res.add_line(*n);
+                    }
+                }
+                Step::Utf16Char(x) => {
+                    if offset < x.end() {
+                        // if the offset is inside a multibyte char it's invalid
+                        // clamp it to the start of the char
+                        let clamp = offset.min(x.start());
+                        return res.to_line_col(clamp);
+                    } else {
+                        res.adjust_col(*x);
+                    }
+                }
+            }
+        };
+    }
+
+    for orig_step in LineIndexStepIter::from(line_index) {
+        loop {
+            let translated_step = state.translate_step(&orig_step);
+            match state.next_steps(&translated_step) {
+                NextSteps::Use => {
+                    test_step!(translated_step);
+                    break;
+                }
+                NextSteps::ReplaceMany(ns) => {
+                    for n in ns {
+                        test_step!(n);
+                    }
+                    break;
+                }
+                NextSteps::AddMany(ns) => {
+                    for n in ns {
+                        test_step!(n);
+                    }
+                }
+            }
+        }
+    }
+
+    loop {
+        match state.next_inserted_steps() {
+            None => break,
+            Some(ns) => {
+                for n in ns {
+                    test_step!(n);
+                }
+            }
+        }
+    }
+
+    res.to_line_col(offset)
+}
+
 #[derive(Debug, Clone)]
 enum Step {
     Newline(TextUnit),
@@ -17,7 +95,7 @@ struct LineIndexStepIter<'a> {
     utf16_chars: Option<(TextUnit, std::slice::Iter<'a, Utf16Char>)>,
 }
 
-impl<'a> LineIndexStepIter<'a> {
+impl LineIndexStepIter<'_> {
     fn from(line_index: &LineIndex) -> LineIndexStepIter {
         let mut x = LineIndexStepIter { line_index, next_newline_idx: 0, utf16_chars: None };
         // skip first newline since it's not real
@@ -26,7 +104,7 @@ impl<'a> LineIndexStepIter<'a> {
     }
 }
 
-impl<'a> Iterator for LineIndexStepIter<'a> {
+impl Iterator for LineIndexStepIter<'_> {
     type Item = Step;
     fn next(&mut self) -> Option<Step> {
         self.utf16_chars
@@ -54,7 +132,7 @@ struct OffsetStepIter<'a> {
     offset: TextUnit,
 }
 
-impl<'a> Iterator for OffsetStepIter<'a> {
+impl Iterator for OffsetStepIter<'_> {
     type Item = Step;
     fn next(&mut self) -> Option<Step> {
         let (next, next_offset) = self
@@ -220,84 +298,16 @@ impl RunningLineCol {
     }
 }
 
-pub fn translate_offset_with_edit(
-    line_index: &LineIndex,
-    offset: TextUnit,
-    text_edit: &TextEdit,
-) -> LineCol {
-    let mut state = Edits::from_text_edit(&text_edit);
-
-    let mut res = RunningLineCol::new();
-
-    macro_rules! test_step {
-        ($x:ident) => {
-            match &$x {
-                Step::Newline(n) => {
-                    if offset < *n {
-                        return res.to_line_col(offset);
-                    } else {
-                        res.add_line(*n);
-                    }
-                }
-                Step::Utf16Char(x) => {
-                    if offset < x.end() {
-                        // if the offset is inside a multibyte char it's invalid
-                        // clamp it to the start of the char
-                        let clamp = offset.min(x.start());
-                        return res.to_line_col(clamp);
-                    } else {
-                        res.adjust_col(*x);
-                    }
-                }
-            }
-        };
-    }
-
-    for orig_step in LineIndexStepIter::from(line_index) {
-        loop {
-            let translated_step = state.translate_step(&orig_step);
-            match state.next_steps(&translated_step) {
-                NextSteps::Use => {
-                    test_step!(translated_step);
-                    break;
-                }
-                NextSteps::ReplaceMany(ns) => {
-                    for n in ns {
-                        test_step!(n);
-                    }
-                    break;
-                }
-                NextSteps::AddMany(ns) => {
-                    for n in ns {
-                        test_step!(n);
-                    }
-                }
-            }
-        }
-    }
-
-    loop {
-        match state.next_inserted_steps() {
-            None => break,
-            Some(ns) => {
-                for n in ns {
-                    test_step!(n);
-                }
-            }
-        }
-    }
-
-    res.to_line_col(offset)
-}
-
 #[cfg(test)]
 mod test {
-    use super::*;
-    use crate::line_index;
     use proptest::{prelude::*, proptest};
     use ra_text_edit::test_utils::{arb_offset, arb_text_with_edit};
     use ra_text_edit::TextEdit;
 
+    use crate::line_index;
+
+    use super::*;
+
     #[derive(Debug)]
     struct ArbTextWithEditAndOffset {
         text: String,
diff --git a/crates/ra_ide/src/symbol_index.rs b/crates/ra_ide_db/src/symbol_index.rs
index 5729eb5b3..64ddf2f95 100644
--- a/crates/ra_ide/src/symbol_index.rs
+++ b/crates/ra_ide_db/src/symbol_index.rs
@@ -19,6 +19,7 @@
 //! for each library (which is assumed to never change) and an FST for each Rust
 //! file in the current workspace, and run a query against the union of all
 //! those FSTs.
+
 use std::{
     fmt,
     hash::{Hash, Hasher},
@@ -29,7 +30,7 @@ use std::{
 use fst::{self, Streamer};
 use ra_db::{
     salsa::{self, ParallelDatabase},
-    SourceDatabaseExt, SourceRootId,
+    FileId, SourceDatabaseExt, SourceRootId,
 };
 use ra_syntax::{
     ast::{self, NameOwner},
@@ -40,10 +41,50 @@ use ra_syntax::{
 #[cfg(not(feature = "wasm"))]
 use rayon::prelude::*;
 
-use crate::{db::RootDatabase, FileId, Query};
+use crate::RootDatabase;
+
+#[derive(Debug)]
+pub struct Query {
+    query: String,
+    lowercased: String,
+    only_types: bool,
+    libs: bool,
+    exact: bool,
+    limit: usize,
+}
+
+impl Query {
+    pub fn new(query: String) -> Query {
+        let lowercased = query.to_lowercase();
+        Query {
+            query,
+            lowercased,
+            only_types: false,
+            libs: false,
+            exact: false,
+            limit: usize::max_value(),
+        }
+    }
+
+    pub fn only_types(&mut self) {
+        self.only_types = true;
+    }
+
+    pub fn libs(&mut self) {
+        self.libs = true;
+    }
+
+    pub fn exact(&mut self) {
+        self.exact = true;
+    }
+
+    pub fn limit(&mut self, limit: usize) {
+        self.limit = limit
+    }
+}
 
 #[salsa::query_group(SymbolsDatabaseStorage)]
-pub(crate) trait SymbolsDatabase: hir::db::HirDatabase {
+pub trait SymbolsDatabase: hir::db::HirDatabase {
     fn file_symbols(&self, file_id: FileId) -> Arc<SymbolIndex>;
     #[salsa::input]
     fn library_symbols(&self, id: SourceRootId) -> Arc<SymbolIndex>;
@@ -68,7 +109,7 @@ fn file_symbols(db: &impl SymbolsDatabase, file_id: FileId) -> Arc<SymbolIndex>
     Arc::new(SymbolIndex::new(symbols))
 }
 
-pub(crate) fn world_symbols(db: &RootDatabase, query: Query) -> Vec<FileSymbol> {
+pub fn world_symbols(db: &RootDatabase, query: Query) -> Vec<FileSymbol> {
     /// Need to wrap Snapshot to provide `Clone` impl for `map_with`
     struct Snap(salsa::Snapshot<RootDatabase>);
     impl Clone for Snap {
@@ -110,16 +151,16 @@ pub(crate) fn world_symbols(db: &RootDatabase, query: Query) -> Vec<FileSymbol>
     query.search(&buf)
 }
 
-pub(crate) fn index_resolve(db: &RootDatabase, name_ref: &ast::NameRef) -> Vec<FileSymbol> {
+pub fn index_resolve(db: &RootDatabase, name_ref: &ast::NameRef) -> Vec<FileSymbol> {
     let name = name_ref.text();
     let mut query = Query::new(name.to_string());
     query.exact();
     query.limit(4);
-    crate::symbol_index::world_symbols(db, query)
+    world_symbols(db, query)
 }
 
 #[derive(Default)]
-pub(crate) struct SymbolIndex {
+pub struct SymbolIndex {
     symbols: Vec<FileSymbol>,
     map: fst::Map,
 }
@@ -178,11 +219,11 @@ impl SymbolIndex {
         SymbolIndex { symbols, map }
     }
 
-    pub(crate) fn len(&self) -> usize {
+    pub fn len(&self) -> usize {
         self.symbols.len()
     }
 
-    pub(crate) fn memory_size(&self) -> usize {
+    pub fn memory_size(&self) -> usize {
         self.map.as_fst().size() + self.symbols.len() * mem::size_of::<FileSymbol>()
     }
 
@@ -262,12 +303,12 @@ fn is_type(kind: SyntaxKind) -> bool {
 /// The actual data that is stored in the index. It should be as compact as
 /// possible.
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub(crate) struct FileSymbol {
-    pub(crate) file_id: FileId,
-    pub(crate) name: SmolStr,
-    pub(crate) ptr: SyntaxNodePtr,
-    pub(crate) name_range: Option<TextRange>,
-    pub(crate) container_name: Option<SmolStr>,
+pub struct FileSymbol {
+    pub file_id: FileId,
+    pub name: SmolStr,
+    pub ptr: SyntaxNodePtr,
+    pub name_range: Option<TextRange>,
+    pub container_name: Option<SmolStr>,
 }
 
 fn source_file_to_file_symbols(source_file: &SourceFile, file_id: FileId) -> Vec<FileSymbol> {
@@ -329,77 +370,3 @@ fn to_file_symbol(node: &SyntaxNode, file_id: FileId) -> Option<FileSymbol> {
         container_name: None,
     })
 }
-
-#[cfg(test)]
-mod tests {
-    use crate::{display::NavigationTarget, mock_analysis::single_file, Query};
-    use ra_syntax::{
-        SmolStr,
-        SyntaxKind::{FN_DEF, STRUCT_DEF},
-    };
-
-    #[test]
-    fn test_world_symbols_with_no_container() {
-        let code = r#"
-    enum FooInner { }
-    "#;
-
-        let mut symbols = get_symbols_matching(code, "FooInner");
-
-        let s = symbols.pop().unwrap();
-
-        assert_eq!(s.name(), "FooInner");
-        assert!(s.container_name().is_none());
-    }
-
-    #[test]
-    fn test_world_symbols_include_container_name() {
-        let code = r#"
-fn foo() {
-    enum FooInner { }
-}
-    "#;
-
-        let mut symbols = get_symbols_matching(code, "FooInner");
-
-        let s = symbols.pop().unwrap();
-
-        assert_eq!(s.name(), "FooInner");
-        assert_eq!(s.container_name(), Some(&SmolStr::new("foo")));
-
-        let code = r#"
-mod foo {
-    struct FooInner;
-}
-    "#;
-
-        let mut symbols = get_symbols_matching(code, "FooInner");
-
-        let s = symbols.pop().unwrap();
-
-        assert_eq!(s.name(), "FooInner");
-        assert_eq!(s.container_name(), Some(&SmolStr::new("foo")));
-    }
-
-    #[test]
-    fn test_world_symbols_are_case_sensitive() {
-        let code = r#"
-fn foo() {}
-
-struct Foo;
-        "#;
-
-        let symbols = get_symbols_matching(code, "Foo");
-
-        let fn_match = symbols.iter().find(|s| s.name() == "foo").map(|s| s.kind());
-        let struct_match = symbols.iter().find(|s| s.name() == "Foo").map(|s| s.kind());
-
-        assert_eq!(fn_match, Some(FN_DEF));
-        assert_eq!(struct_match, Some(STRUCT_DEF));
-    }
-
-    fn get_symbols_matching(text: &str, query: &str) -> Vec<NavigationTarget> {
-        let (analysis, _) = single_file(text);
-        analysis.symbol_search(Query::new(query.into())).unwrap()
-    }
-}
diff --git a/crates/ra_ide/src/wasm_shims.rs b/crates/ra_ide_db/src/wasm_shims.rs
index 088cc9be4..7af9f9d9b 100644
--- a/crates/ra_ide/src/wasm_shims.rs
+++ b/crates/ra_ide_db/src/wasm_shims.rs
@@ -1,4 +1,4 @@
-//! FIXME: write short doc here
+//! A version of `std::time::Instant` that doesn't panic in WASM.
 
 #[cfg(not(feature = "wasm"))]
 pub use std::time::Instant;