37 files changed, 706 insertions, 671 deletions

diff --git a/crates/ra_ide_api/src/call_info.rs b/crates/ra_ide_api/src/call_info.rs
index 29fa7d30b..4413aec73 100644
--- a/crates/ra_ide_api/src/call_info.rs
+++ b/crates/ra_ide_api/src/call_info.rs
@@ -2,13 +2,11 @@ use test_utils::tested_by;
 use ra_db::SourceDatabase;
 use ra_syntax::{
     AstNode, SyntaxNode, TextUnit,
-    SyntaxKind::FN_DEF,
     ast::{self, ArgListOwner},
     algo::find_node_at_offset,
 };
-use hir::Docs;
 
-use crate::{FilePosition, CallInfo, db::RootDatabase};
+use crate::{FilePosition, CallInfo, FunctionSignature, db::RootDatabase};
 
 /// Computes parameter information for the given call expression.
 pub(crate) fn call_info(db: &RootDatabase, position: FilePosition) -> Option<CallInfo> {
@@ -19,19 +17,26 @@ pub(crate) fn call_info(db: &RootDatabase, position: FilePosition) -> Option<Cal
     let calling_node = FnCallNode::with_node(syntax, position.offset)?;
     let name_ref = calling_node.name_ref()?;
 
-    // Resolve the function's NameRef (NOTE: this isn't entirely accurate).
-    let file_symbols = crate::symbol_index::index_resolve(db, name_ref);
-    let symbol = file_symbols.into_iter().find(|it| it.ptr.kind() == FN_DEF)?;
-    let fn_file = db.parse(symbol.file_id);
-    let fn_def = symbol.ptr.to_node(&fn_file);
-    let fn_def = ast::FnDef::cast(fn_def).unwrap();
-    let function = hir::source_binder::function_from_source(db, symbol.file_id, fn_def)?;
+    let analyzer = hir::SourceAnalyzer::new(db, position.file_id, name_ref.syntax(), None);
+    let function = match calling_node {
+        FnCallNode::CallExpr(expr) => {
+            //FIXME: apply subst
+            let (callable_def, _subst) =
+                analyzer.type_of(db, expr.expr()?.into())?.as_callable()?;
+            match callable_def {
+                hir::CallableDef::Function(it) => it,
+                //FIXME: handle other callables
+                _ => return None,
+            }
+        }
+        FnCallNode::MethodCallExpr(expr) => analyzer.resolve_method_call(expr)?,
+    };
 
-    let mut call_info = CallInfo::new(db, function, fn_def)?;
+    let mut call_info = CallInfo::new(db, function);
 
     // If we have a calling expression let's find which argument we are on
-    let num_params = call_info.parameters.len();
-    let has_self = fn_def.param_list().and_then(|l| l.self_param()).is_some();
+    let num_params = call_info.parameters().len();
+    let has_self = function.signature(db).has_self_param();
 
     if num_params == 1 {
         if !has_self {
@@ -75,7 +80,7 @@ enum FnCallNode<'a> {
 }
 
 impl<'a> FnCallNode<'a> {
-    pub fn with_node(syntax: &'a SyntaxNode, offset: TextUnit) -> Option<FnCallNode<'a>> {
+    fn with_node(syntax: &'a SyntaxNode, offset: TextUnit) -> Option<FnCallNode<'a>> {
         if let Some(expr) = find_node_at_offset::<ast::CallExpr>(syntax, offset) {
             return Some(FnCallNode::CallExpr(expr));
         }
@@ -85,7 +90,7 @@ impl<'a> FnCallNode<'a> {
         None
     }
 
-    pub fn name_ref(&self) -> Option<&'a ast::NameRef> {
+    fn name_ref(&self) -> Option<&'a ast::NameRef> {
         match *self {
             FnCallNode::CallExpr(call_expr) => Some(match call_expr.expr()?.kind() {
                 ast::ExprKind::PathExpr(path_expr) => path_expr.path()?.segment()?.name_ref()?,
@@ -98,7 +103,7 @@ impl<'a> FnCallNode<'a> {
         }
     }
 
-    pub fn arg_list(&self) -> Option<&'a ast::ArgList> {
+    fn arg_list(&self) -> Option<&'a ast::ArgList> {
         match *self {
             FnCallNode::CallExpr(expr) => expr.arg_list(),
             FnCallNode::MethodCallExpr(expr) => expr.arg_list(),
@@ -107,28 +112,15 @@ impl<'a> FnCallNode<'a> {
 }
 
 impl CallInfo {
-    fn new(db: &RootDatabase, function: hir::Function, node: &ast::FnDef) -> Option<Self> {
-        let label = crate::completion::function_label(node)?;
-        let doc = function.docs(db);
+    fn new(db: &RootDatabase, function: hir::Function) -> Self {
+        let signature = FunctionSignature::from_hir(db, function);
 
-        Some(CallInfo { parameters: param_list(node), label, doc, active_parameter: None })
+        CallInfo { signature, active_parameter: None }
     }
-}
 
-fn param_list(node: &ast::FnDef) -> Vec<String> {
-    let mut res = vec![];
-    if let Some(param_list) = node.param_list() {
-        if let Some(self_param) = param_list.self_param() {
-            res.push(self_param.syntax().text().to_string())
-        }
-
-        // Maybe use param.pat here? See if we can just extract the name?
-        //res.extend(param_list.params().map(|p| p.syntax().text().to_string()));
-        res.extend(
-            param_list.params().filter_map(|p| p.pat()).map(|pat| pat.syntax().text().to_string()),
-        );
+    fn parameters(&self) -> &[String] {
+        &self.signature.parameters
     }
-    res
 }
 
 #[cfg(test)]
@@ -139,19 +131,30 @@ mod tests {
 
     use super::*;
 
+    // These are only used when testing
+    impl CallInfo {
+        fn doc(&self) -> Option<hir::Documentation> {
+            self.signature.doc.clone()
+        }
+
+        fn label(&self) -> String {
+            self.signature.to_string()
+        }
+    }
+
     fn call_info(text: &str) -> CallInfo {
         let (analysis, position) = single_file_with_position(text);
         analysis.call_info(position).unwrap().unwrap()
     }
 
     #[test]
-    fn test_fn_signature_two_args_first() {
+    fn test_fn_signature_two_args_firstx() {
         let info = call_info(
             r#"fn foo(x: u32, y: u32) -> u32 {x + y}
 fn bar() { foo(<|>3, ); }"#,
         );
 
-        assert_eq!(info.parameters, vec!("x".to_string(), "y".to_string()));
+        assert_eq!(info.parameters(), ["x: u32", "y: u32"]);
         assert_eq!(info.active_parameter, Some(0));
     }
 
@@ -162,7 +165,7 @@ fn bar() { foo(<|>3, ); }"#,
 fn bar() { foo(3, <|>); }"#,
         );
 
-        assert_eq!(info.parameters, vec!("x".to_string(), "y".to_string()));
+        assert_eq!(info.parameters(), ["x: u32", "y: u32"]);
         assert_eq!(info.active_parameter, Some(1));
     }
 
@@ -173,18 +176,57 @@ fn bar() { foo(3, <|>); }"#,
 fn bar() { foo(<|>); }"#,
         );
 
-        assert_eq!(info.parameters, vec!("x".to_string(), "y".to_string()));
+        assert_eq!(info.parameters(), ["x: u32", "y: u32"]);
+        assert_eq!(info.active_parameter, Some(0));
+    }
+
+    #[test]
+    fn test_fn_signature_two_args_first_generics() {
+        let info = call_info(
+            r#"fn foo<T, U: Copy + Display>(x: T, y: U) -> u32 where T: Copy + Display, U: Debug {x + y}
+fn bar() { foo(<|>3, ); }"#,
+        );
+
+        assert_eq!(info.parameters(), ["x: T", "y: U"]);
+        assert_eq!(
+            info.label(),
+            r#"
+fn foo<T, U: Copy + Display>(x: T, y: U) -> u32
+where T: Copy + Display,
+      U: Debug
+    "#
+            .trim()
+        );
         assert_eq!(info.active_parameter, Some(0));
     }
 
     #[test]
+    fn test_fn_signature_no_params() {
+        let info = call_info(
+            r#"fn foo<T>() -> T where T: Copy + Display {}
+fn bar() { foo(<|>); }"#,
+        );
+
+        assert!(info.parameters().is_empty());
+        assert_eq!(
+            info.label(),
+            r#"
+fn foo<T>() -> T
+where T: Copy + Display
+    "#
+            .trim()
+        );
+        assert!(info.active_parameter.is_none());
+    }
+
+    #[test]
     fn test_fn_signature_for_impl() {
         let info = call_info(
             r#"struct F; impl F { pub fn new() { F{}} }
 fn bar() {let _ : F = F::new(<|>);}"#,
         );
 
-        assert_eq!(info.parameters, Vec::<String>::new());
+        assert!(info.parameters().is_empty());
         assert_eq!(info.active_parameter, None);
     }
 
@@ -206,7 +248,7 @@ fn bar() {
 }"#,
         );
 
-        assert_eq!(info.parameters, vec!["&self".to_string()]);
+        assert_eq!(info.parameters(), ["&self"]);
         assert_eq!(info.active_parameter, None);
     }
 
@@ -228,7 +270,7 @@ fn bar() {
 }"#,
         );
 
-        assert_eq!(info.parameters, vec!["&self".to_string(), "x".to_string()]);
+        assert_eq!(info.parameters(), ["&self", "x: i32"]);
         assert_eq!(info.active_parameter, Some(1));
     }
 
@@ -248,10 +290,10 @@ fn bar() {
 "#,
         );
 
-        assert_eq!(info.parameters, vec!["j".to_string()]);
+        assert_eq!(info.parameters(), ["j: u32"]);
         assert_eq!(info.active_parameter, Some(0));
-        assert_eq!(info.label, "fn foo(j: u32) -> u32".to_string());
-        assert_eq!(info.doc.map(|it| it.into()), Some("test".to_string()));
+        assert_eq!(info.label(), "fn foo(j: u32) -> u32");
+        assert_eq!(info.doc().map(|it| it.into()), Some("test".to_string()));
     }
 
     #[test]
@@ -276,11 +318,11 @@ pub fn do() {
 }"#,
         );
 
-        assert_eq!(info.parameters, vec!["x".to_string()]);
+        assert_eq!(info.parameters(), ["x: i32"]);
         assert_eq!(info.active_parameter, Some(0));
-        assert_eq!(info.label, "pub fn add_one(x: i32) -> i32".to_string());
+        assert_eq!(info.label(), "pub fn add_one(x: i32) -> i32");
         assert_eq!(
-            info.doc.map(|it| it.into()),
+            info.doc().map(|it| it.into()),
             Some(
                 r#"Adds one to the number given.
 
@@ -322,11 +364,11 @@ pub fn do_it() {
 }"#,
         );
 
-        assert_eq!(info.parameters, vec!["x".to_string()]);
+        assert_eq!(info.parameters(), ["x: i32"]);
         assert_eq!(info.active_parameter, Some(0));
-        assert_eq!(info.label, "pub fn add_one(x: i32) -> i32".to_string());
+        assert_eq!(info.label(), "pub fn add_one(x: i32) -> i32");
         assert_eq!(
-            info.doc.map(|it| it.into()),
+            info.doc().map(|it| it.into()),
             Some(
                 r#"Adds one to the number given.
 
@@ -346,11 +388,9 @@ assert_eq!(6, my_crate::add_one(5));
     fn test_fn_signature_with_docs_from_actix() {
         let info = call_info(
             r#"
-pub trait WriteHandler<E>
-where
-    Self: Actor,
-    Self::Context: ActorContext,
-{
+struct WriteHandler<E>;
+
+impl<E> WriteHandler<E> {
     /// Method is called when writer emits error.
     ///
     /// If this method returns `ErrorAction::Continue` writer processing
@@ -367,18 +407,17 @@ where
     }
 }
 
-pub fn foo() {
-    WriteHandler r;
+pub fn foo(mut r: WriteHandler<()>) {
     r.finished(<|>);
 }
 
 "#,
         );
 
-        assert_eq!(info.parameters, vec!["&mut self".to_string(), "ctx".to_string()]);
+        assert_eq!(info.parameters(), ["&mut self", "ctx: &mut Self::Context"]);
         assert_eq!(info.active_parameter, Some(1));
         assert_eq!(
-            info.doc.map(|it| it.into()),
+            info.doc().map(|it| it.into()),
             Some(
                 r#"Method is called when writer finishes.
 
diff --git a/crates/ra_ide_api/src/completion.rs b/crates/ra_ide_api/src/completion.rs
index a846a7a3c..deff59cd3 100644
--- a/crates/ra_ide_api/src/completion.rs
+++ b/crates/ra_ide_api/src/completion.rs
@@ -13,7 +13,6 @@ mod complete_scope;
 mod complete_postfix;
 
 use ra_db::SourceDatabase;
-use ra_syntax::{ast::{self, AstNode}, SyntaxKind::{ATTR, COMMENT}};
 
 use crate::{
     db,
@@ -70,43 +69,3 @@ pub(crate) fn completions(db: &db::RootDatabase, position: FilePosition) -> Opti
     complete_postfix::complete_postfix(&mut acc, &ctx);
     Some(acc)
 }
-
-pub fn function_label(node: &ast::FnDef) -> Option<String> {
-    let label: String = if let Some(body) = node.body() {
-        let body_range = body.syntax().range();
-        let label: String = node
-            .syntax()
-            .children_with_tokens()
-            .filter(|child| !child.range().is_subrange(&body_range)) // Filter out body
-            .filter(|child| !(child.kind() == COMMENT || child.kind() == ATTR)) // Filter out comments and attrs
-            .map(|node| node.to_string())
-            .collect();
-        label
-    } else {
-        node.syntax().text().to_string()
-    };
-
-    Some(label.trim().to_owned())
-}
-
-pub fn const_label(node: &ast::ConstDef) -> String {
-    let label: String = node
-        .syntax()
-        .children_with_tokens()
-        .filter(|child| !(child.kind() == COMMENT || child.kind() == ATTR))
-        .map(|node| node.to_string())
-        .collect();
-
-    label.trim().to_owned()
-}
-
-pub fn type_label(node: &ast::TypeAliasDef) -> String {
-    let label: String = node
-        .syntax()
-        .children_with_tokens()
-        .filter(|child| !(child.kind() == COMMENT || child.kind() == ATTR))
-        .map(|node| node.to_string())
-        .collect();
-
-    label.trim().to_owned()
-}
diff --git a/crates/ra_ide_api/src/completion/complete_dot.rs b/crates/ra_ide_api/src/completion/complete_dot.rs
index 18b2d68d5..4a111aba5 100644
--- a/crates/ra_ide_api/src/completion/complete_dot.rs
+++ b/crates/ra_ide_api/src/completion/complete_dot.rs
@@ -4,17 +4,10 @@ use crate::completion::{CompletionContext, Completions};
 
 /// Complete dot accesses, i.e. fields or methods (currently only fields).
 pub(super) fn complete_dot(acc: &mut Completions, ctx: &CompletionContext) {
-    let (function, receiver) = match (&ctx.function, ctx.dot_receiver) {
-        (Some(function), Some(receiver)) => (function, receiver),
-        _ => return,
-    };
-    let infer_result = function.infer(ctx.db);
-    let source_map = function.body_source_map(ctx.db);
-    let expr = match source_map.node_expr(receiver) {
-        Some(expr) => expr,
+    let receiver_ty = match ctx.dot_receiver.and_then(|it| ctx.analyzer.type_of(ctx.db, it)) {
+        Some(it) => it,
         None => return,
     };
-    let receiver_ty = infer_result[expr].clone();
     if !ctx.is_call {
         complete_fields(acc, ctx, receiver_ty.clone());
     }
@@ -55,29 +48,41 @@ fn complete_methods(acc: &mut Completions, ctx: &CompletionContext, receiver: Ty
 
 #[cfg(test)]
 mod tests {
-    use crate::completion::{check_completion, CompletionKind};
+    use crate::completion::{do_completion, CompletionKind, CompletionItem};
+    use insta::assert_debug_snapshot_matches;
 
-    fn check_ref_completion(name: &str, code: &str) {
-        check_completion(name, code, CompletionKind::Reference);
+    fn do_ref_completion(code: &str) -> Vec<CompletionItem> {
+        do_completion(code, CompletionKind::Reference)
     }
 
     #[test]
     fn test_struct_field_completion() {
-        check_ref_completion(
-            "struct_field_completion",
-            r"
-            struct A { the_field: u32 }
-            fn foo(a: A) {
-               a.<|>
-            }
-            ",
+        assert_debug_snapshot_matches!(
+        do_ref_completion(
+                r"
+                struct A { the_field: u32 }
+                fn foo(a: A) {
+                a.<|>
+                }
+                ",
+        ),
+            @r###"[
+    CompletionItem {
+        label: "the_field",
+        source_range: [94; 94),
+        delete: [94; 94),
+        insert: "the_field",
+        kind: Field,
+        detail: "u32"
+    }
+]"###
         );
     }
 
     #[test]
     fn test_struct_field_completion_self() {
-        check_ref_completion(
-            "struct_field_completion_self",
+        assert_debug_snapshot_matches!(
+        do_ref_completion(
             r"
             struct A {
                 /// This is the_field
@@ -89,13 +94,35 @@ mod tests {
                 }
             }
             ",
+        ),
+        @r###"[
+    CompletionItem {
+        label: "foo",
+        source_range: [187; 187),
+        delete: [187; 187),
+        insert: "foo()$0",
+        kind: Method,
+        detail: "fn foo(self)"
+    },
+    CompletionItem {
+        label: "the_field",
+        source_range: [187; 187),
+        delete: [187; 187),
+        insert: "the_field",
+        kind: Field,
+        detail: "(u32,)",
+        documentation: Documentation(
+            "This is the_field"
+        )
+    }
+]"###
         );
     }
 
     #[test]
     fn test_struct_field_completion_autoderef() {
-        check_ref_completion(
-            "struct_field_completion_autoderef",
+        assert_debug_snapshot_matches!(
+        do_ref_completion(
             r"
             struct A { the_field: (u32, i32) }
             impl A {
@@ -104,26 +131,47 @@ mod tests {
                 }
             }
             ",
+        ),
+        @r###"[
+    CompletionItem {
+        label: "foo",
+        source_range: [126; 126),
+        delete: [126; 126),
+        insert: "foo()$0",
+        kind: Method,
+        detail: "fn foo(&self)"
+    },
+    CompletionItem {
+        label: "the_field",
+        source_range: [126; 126),
+        delete: [126; 126),
+        insert: "the_field",
+        kind: Field,
+        detail: "(u32, i32)"
+    }
+]"###
         );
     }
 
     #[test]
     fn test_no_struct_field_completion_for_method_call() {
-        check_ref_completion(
-            "no_struct_field_completion_for_method_call",
+        assert_debug_snapshot_matches!(
+        do_ref_completion(
             r"
             struct A { the_field: u32 }
             fn foo(a: A) {
                a.<|>()
             }
             ",
+        ),
+        @"[]"
         );
     }
 
     #[test]
     fn test_method_completion() {
-        check_ref_completion(
-            "method_completion",
+        assert_debug_snapshot_matches!(
+        do_ref_completion(
             r"
             struct A {}
             impl A {
@@ -133,13 +181,24 @@ mod tests {
                a.<|>
             }
             ",
+        ),
+        @r###"[
+    CompletionItem {
+        label: "the_method",
+        source_range: [144; 144),
+        delete: [144; 144),
+        insert: "the_method()$0",
+        kind: Method,
+        detail: "fn the_method(&self)"
+    }
+]"###
         );
     }
 
     #[test]
     fn test_no_non_self_method() {
-        check_ref_completion(
-            "no_non_self_method",
+        assert_debug_snapshot_matches!(
+        do_ref_completion(
             r"
             struct A {}
             impl A {
@@ -149,13 +208,15 @@ mod tests {
                a.<|>
             }
             ",
+        ),
+        @"[]"
         );
     }
 
     #[test]
     fn test_method_attr_filtering() {
-        check_ref_completion(
-            "method_attr_filtering",
+        assert_debug_snapshot_matches!(
+        do_ref_completion(
             r"
             struct A {}
             impl A {
@@ -169,26 +230,56 @@ mod tests {
                a.<|>
             }
             ",
+        ),
+        @r###"[
+    CompletionItem {
+        label: "the_method",
+        source_range: [249; 249),
+        delete: [249; 249),
+        insert: "the_method()$0",
+        kind: Method,
+        detail: "fn the_method(&self)"
+    }
+]"###
         );
     }
 
     #[test]
     fn test_tuple_field_completion() {
-        check_ref_completion(
-            "tuple_field_completion",
+        assert_debug_snapshot_matches!(
+        do_ref_completion(
             r"
             fn foo() {
                let b = (0, 3.14);
                b.<|>
             }
             ",
+        ),
+        @r###"[
+    CompletionItem {
+        label: "0",
+        source_range: [75; 75),
+        delete: [75; 75),
+        insert: "0",
+        kind: Field,
+        detail: "i32"
+    },
+    CompletionItem {
+        label: "1",
+        source_range: [75; 75),
+        delete: [75; 75),
+        insert: "1",
+        kind: Field,
+        detail: "f64"
+    }
+]"###
         );
     }
 
     #[test]
     fn test_tuple_field_inference() {
-        check_ref_completion(
-            "tuple_field_inference",
+        assert_debug_snapshot_matches!(
+        do_ref_completion(
             r"
             pub struct S;
             impl S {
@@ -204,6 +295,41 @@ mod tests {
                 }
             }
             ",
+        ),
+        @r###"[
+    CompletionItem {
+        label: "blah",
+        source_range: [299; 300),
+        delete: [299; 300),
+        insert: "blah()$0",
+        kind: Method,
+        detail: "pub fn blah(&self)"
+    }
+]"###
+        );
+    }
+
+    #[test]
+    fn test_completion_works_in_consts() {
+        assert_debug_snapshot_matches!(
+        do_ref_completion(
+            r"
+            struct A { the_field: u32 }
+            const X: u32 = {
+                A { the_field: 92 }.<|>
+            };
+            ",
+        ),
+        @r###"[
+    CompletionItem {
+        label: "the_field",
+        source_range: [106; 106),
+        delete: [106; 106),
+        insert: "the_field",
+        kind: Field,
+        detail: "u32"
+    }
+]"###
         );
     }
 }
diff --git a/crates/ra_ide_api/src/completion/complete_fn_param.rs b/crates/ra_ide_api/src/completion/complete_fn_param.rs
index f87ccdeb9..85ef62f52 100644
--- a/crates/ra_ide_api/src/completion/complete_fn_param.rs
+++ b/crates/ra_ide_api/src/completion/complete_fn_param.rs
@@ -54,48 +54,79 @@ pub(super) fn complete_fn_param(acc: &mut Completions, ctx: &CompletionContext)
 
 #[cfg(test)]
 mod tests {
-    use crate::completion::{check_completion, CompletionKind};
+    use crate::completion::{do_completion, CompletionItem, CompletionKind};
+    use insta::assert_debug_snapshot_matches;
 
-    fn check_magic_completion(name: &str, code: &str) {
-        check_completion(name, code, CompletionKind::Magic);
+    fn do_magic_completion(code: &str) -> Vec<CompletionItem> {
+        do_completion(code, CompletionKind::Magic)
     }
 
     #[test]
     fn test_param_completion_last_param() {
-        check_magic_completion(
-            "param_completion_last_param",
-            r"
-            fn foo(file_id: FileId) {}
-            fn bar(file_id: FileId) {}
-            fn baz(file<|>) {}
-            ",
+        assert_debug_snapshot_matches!(
+        do_magic_completion(
+                r"
+                fn foo(file_id: FileId) {}
+                fn bar(file_id: FileId) {}
+                fn baz(file<|>) {}
+                ",
+        ),
+            @r###"[
+    CompletionItem {
+        label: "file_id: FileId",
+        source_range: [110; 114),
+        delete: [110; 114),
+        insert: "file_id: FileId",
+        lookup: "file_id"
+    }
+]"###
         );
     }
 
     #[test]
     fn test_param_completion_nth_param() {
-        check_magic_completion(
-            "param_completion_nth_param",
-            r"
-            fn foo(file_id: FileId) {}
-            fn bar(file_id: FileId) {}
-            fn baz(file<|>, x: i32) {}
-            ",
+        assert_debug_snapshot_matches!(
+        do_magic_completion(
+                r"
+                fn foo(file_id: FileId) {}
+                fn bar(file_id: FileId) {}
+                fn baz(file<|>, x: i32) {}
+                ",
+        ),
+            @r###"[
+    CompletionItem {
+        label: "file_id: FileId",
+        source_range: [110; 114),
+        delete: [110; 114),
+        insert: "file_id: FileId",
+        lookup: "file_id"
+    }
+]"###
         );
     }
 
     #[test]
     fn test_param_completion_trait_param() {
-        check_magic_completion(
-            "param_completion_trait_param",
-            r"
-            pub(crate) trait SourceRoot {
-                pub fn contains(&self, file_id: FileId) -> bool;
-                pub fn module_map(&self) -> &ModuleMap;
-                pub fn lines(&self, file_id: FileId) -> &LineIndex;
-                pub fn syntax(&self, file<|>)
-            }
-            ",
+        assert_debug_snapshot_matches!(
+        do_magic_completion(
+                r"
+                pub(crate) trait SourceRoot {
+                    pub fn contains(&self, file_id: FileId) -> bool;
+                    pub fn module_map(&self) -> &ModuleMap;
+                    pub fn lines(&self, file_id: FileId) -> &LineIndex;
+                    pub fn syntax(&self, file<|>)
+                }
+                ",
+        ),
+            @r###"[
+    CompletionItem {
+        label: "file_id: FileId",
+        source_range: [289; 293),
+        delete: [289; 293),
+        insert: "file_id: FileId",
+        lookup: "file_id"
+    }
+]"###
         );
     }
 }
diff --git a/crates/ra_ide_api/src/completion/complete_path.rs b/crates/ra_ide_api/src/completion/complete_path.rs
index e54fe7b7e..bc03a7095 100644
--- a/crates/ra_ide_api/src/completion/complete_path.rs
+++ b/crates/ra_ide_api/src/completion/complete_path.rs
@@ -1,4 +1,4 @@
-use hir::Resolution;
+use hir::{Resolution, Either};
 use ra_syntax::AstNode;
 use test_utils::tested_by;
 
@@ -9,7 +9,7 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
         Some(path) => path.clone(),
         _ => return,
     };
-    let def = match ctx.resolver.resolve_path(ctx.db, &path).take_types() {
+    let def = match ctx.analyzer.resolve_hir_path(ctx.db, &path).take_types() {
         Some(Resolution::Def(def)) => def,
         _ => return,
     };
@@ -19,10 +19,8 @@ pub(super) fn complete_path(acc: &mut Completions, ctx: &CompletionContext) {
             for (name, res) in module_scope.entries() {
                 if Some(module) == ctx.module {
                     if let Some(import) = res.import {
-                        if let hir::ImportSource::UseTree(tree) =
-                            module.import_source(ctx.db, import)
-                        {
-                            if tree.syntax().range().contains_inclusive(ctx.offset) {
+                        if let Either::A(use_tree) = module.import_source(ctx.db, import) {
+                            if use_tree.syntax().range().contains_inclusive(ctx.offset) {
                                 // for `use self::foo<|>`, don't suggest `foo` as a completion
                                 tested_by!(dont_complete_current_use);
                                 continue;
diff --git a/crates/ra_ide_api/src/completion/complete_pattern.rs b/crates/ra_ide_api/src/completion/complete_pattern.rs
index 7abcd019b..0ef248687 100644
--- a/crates/ra_ide_api/src/completion/complete_pattern.rs
+++ b/crates/ra_ide_api/src/completion/complete_pattern.rs
@@ -7,7 +7,7 @@ pub(super) fn complete_pattern(acc: &mut Completions, ctx: &CompletionContext) {
     }
     // FIXME: ideally, we should look at the type we are matching against and
     // suggest variants + auto-imports
-    let names = ctx.resolver.all_names(ctx.db);
+    let names = ctx.analyzer.all_names(ctx.db);
     for (name, res) in names.into_iter() {
         let r = res.as_ref();
         let def = match r.take_types().or(r.take_values()) {
diff --git a/crates/ra_ide_api/src/completion/complete_scope.rs b/crates/ra_ide_api/src/completion/complete_scope.rs
index 6146b7bb6..fd256fc3b 100644
--- a/crates/ra_ide_api/src/completion/complete_scope.rs
+++ b/crates/ra_ide_api/src/completion/complete_scope.rs
@@ -4,7 +4,7 @@ pub(super) fn complete_scope(acc: &mut Completions, ctx: &CompletionContext) {
     if !ctx.is_trivial_path {
         return;
     }
-    let names = ctx.resolver.all_names(ctx.db);
+    let names = ctx.analyzer.all_names(ctx.db);
 
     names.into_iter().for_each(|(name, res)| acc.add_resolution(ctx, name.to_string(), &res));
 }
@@ -145,7 +145,7 @@ mod tests {
         check_reference_completion(
             "dont_show_both_completions_for_shadowing",
             r"
-            fn foo() -> {
+            fn foo() {
                 let bar = 92;
                 {
                     let bar = 62;
diff --git a/crates/ra_ide_api/src/completion/complete_struct_literal.rs b/crates/ra_ide_api/src/completion/complete_struct_literal.rs
index f58bcd03e..48fbf67f7 100644
--- a/crates/ra_ide_api/src/completion/complete_struct_literal.rs
+++ b/crates/ra_ide_api/src/completion/complete_struct_literal.rs
@@ -4,17 +4,10 @@ use crate::completion::{CompletionContext, Completions};
 
 /// Complete fields in fields literals.
 pub(super) fn complete_struct_literal(acc: &mut Completions, ctx: &CompletionContext) {
-    let (function, struct_lit) = match (&ctx.function, ctx.struct_lit_syntax) {
-        (Some(function), Some(struct_lit)) => (function, struct_lit),
-        _ => return,
-    };
-    let infer_result = function.infer(ctx.db);
-    let source_map = function.body_source_map(ctx.db);
-    let expr = match source_map.node_expr(struct_lit.into()) {
-        Some(expr) => expr,
+    let ty = match ctx.struct_lit_syntax.and_then(|it| ctx.analyzer.type_of(ctx.db, it.into())) {
+        Some(it) => it,
         None => return,
     };
-    let ty = infer_result[expr].clone();
     let (adt, substs) = match ty.as_adt() {
         Some(res) => res,
         _ => return,
diff --git a/crates/ra_ide_api/src/completion/completion_context.rs b/crates/ra_ide_api/src/completion/completion_context.rs
index 65dffa470..359f2cffa 100644
--- a/crates/ra_ide_api/src/completion/completion_context.rs
+++ b/crates/ra_ide_api/src/completion/completion_context.rs
@@ -5,7 +5,7 @@ use ra_syntax::{
     algo::{find_token_at_offset, find_covering_element, find_node_at_offset},
     SyntaxKind::*,
 };
-use hir::{source_binder, Resolver};
+use hir::source_binder;
 
 use crate::{db, FilePosition};
 
@@ -14,11 +14,10 @@ use crate::{db, FilePosition};
 #[derive(Debug)]
 pub(crate) struct CompletionContext<'a> {
     pub(super) db: &'a db::RootDatabase,
+    pub(super) analyzer: hir::SourceAnalyzer,
     pub(super) offset: TextUnit,
     pub(super) token: SyntaxToken<'a>,
-    pub(super) resolver: Resolver,
     pub(super) module: Option<hir::Module>,
-    pub(super) function: Option<hir::Function>,
     pub(super) function_syntax: Option<&'a ast::FnDef>,
     pub(super) use_item_syntax: Option<&'a ast::UseItem>,
     pub(super) struct_lit_syntax: Option<&'a ast::StructLit>,
@@ -47,16 +46,16 @@ impl<'a> CompletionContext<'a> {
         original_file: &'a SourceFile,
         position: FilePosition,
     ) -> Option<CompletionContext<'a>> {
-        let resolver = source_binder::resolver_for_position(db, position);
         let module = source_binder::module_from_position(db, position);
         let token = find_token_at_offset(original_file.syntax(), position.offset).left_biased()?;
+        let analyzer =
+            hir::SourceAnalyzer::new(db, position.file_id, token.parent(), Some(position.offset));
         let mut ctx = CompletionContext {
             db,
+            analyzer,
             token,
             offset: position.offset,
-            resolver,
             module,
-            function: None,
             function_syntax: None,
             use_item_syntax: None,
             struct_lit_syntax: None,
@@ -147,10 +146,6 @@ impl<'a> CompletionContext<'a> {
             .ancestors()
             .take_while(|it| it.kind() != SOURCE_FILE && it.kind() != MODULE)
             .find_map(ast::FnDef::cast);
-        if let (Some(module), Some(fn_def)) = (self.module, self.function_syntax) {
-            let function = source_binder::function_from_module(self.db, module, fn_def);
-            self.function = Some(function);
-        }
 
         let parent = match name_ref.syntax().parent() {
             Some(it) => it,
diff --git a/crates/ra_ide_api/src/completion/presentation.rs b/crates/ra_ide_api/src/completion/presentation.rs
index 28c8f83ab..9aa346688 100644
--- a/crates/ra_ide_api/src/completion/presentation.rs
+++ b/crates/ra_ide_api/src/completion/presentation.rs
@@ -6,6 +6,9 @@ use ra_syntax::ast::NameOwner;
 
 use crate::completion::{
     Completions, CompletionKind, CompletionItemKind, CompletionContext, CompletionItem,
+};
+
+use crate::display::{
     function_label, const_label, type_label,
 };
 
@@ -101,7 +104,7 @@ impl Completions {
                 CompletionItemKind::Function
             })
             .set_documentation(func.docs(ctx.db))
-            .set_detail(detail);
+            .detail(detail);
         // If not an import, add parenthesis automatically.
         if ctx.use_item_syntax.is_none() && !ctx.is_call {
             tested_by!(inserts_parens_for_function_calls);
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__dont_show_both_completions_for_shadowing.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__dont_show_both_completions_for_shadowing.snap
index 87691b304..34adcda6c 100644
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__dont_show_both_completions_for_shadowing.snap
+++ b/crates/ra_ide_api/src/completion/snapshots/completion_item__dont_show_both_completions_for_shadowing.snap
@@ -1,23 +1,23 @@
 ---
-created: "2019-02-18T09:22:24.188564584Z"
-creator: insta@0.6.2
+created: "2019-04-04T14:52:24.531844100Z"
+creator: insta@0.7.4
 source: crates/ra_ide_api/src/completion/completion_item.rs
 expression: kind_completions
 ---
 [
     CompletionItem {
         label: "bar",
-        source_range: [129; 129),
-        delete: [129; 129),
+        source_range: [126; 126),
+        delete: [126; 126),
         insert: "bar",
         kind: Binding
     },
     CompletionItem {
         label: "foo",
-        source_range: [129; 129),
-        delete: [129; 129),
+        source_range: [126; 126),
+        delete: [126; 126),
         insert: "foo()$0",
         kind: Function,
-        detail: "fn foo() ->"
+        detail: "fn foo()"
     }
 ]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__method_attr_filtering.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__method_attr_filtering.snap
deleted file mode 100644
index ce8af2159..000000000
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__method_attr_filtering.snap
+++ /dev/null
@@ -1,16 +0,0 @@
----
-created: "2019-02-18T09:22:23.941335305Z"
-creator: [email protected]
-source: crates/ra_ide_api/src/completion/completion_item.rs
-expression: kind_completions
----
-[
-    CompletionItem {
-        label: "the_method",
-        source_range: [249; 249),
-        delete: [249; 249),
-        insert: "the_method()$0",
-        kind: Method,
-        detail: "fn the_method(&self)"
-    }
-]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__method_completion.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__method_completion.snap
deleted file mode 100644
index 41a10de14..000000000
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__method_completion.snap
+++ /dev/null
@@ -1,16 +0,0 @@
----
-created: "2019-02-18T09:22:23.939676100Z"
-creator: [email protected]
-source: crates/ra_ide_api/src/completion/completion_item.rs
-expression: kind_completions
----
-[
-    CompletionItem {
-        label: "the_method",
-        source_range: [144; 144),
-        delete: [144; 144),
-        insert: "the_method()$0",
-        kind: Method,
-        detail: "fn the_method(&self)"
-    }
-]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__no_non_self_method.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__no_non_self_method.snap
deleted file mode 100644
index 7cc827532..000000000
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__no_non_self_method.snap
+++ /dev/null
@@ -1,7 +0,0 @@
----
-created: "2019-01-22T14:45:00.552379600+00:00"
-creator: [email protected]
-expression: kind_completions
-source: "crates\\ra_ide_api\\src\\completion\\completion_item.rs"
----
-[]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__no_struct_field_completion_for_method_call.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__no_struct_field_completion_for_method_call.snap
deleted file mode 100644
index 7cc827532..000000000
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__no_struct_field_completion_for_method_call.snap
+++ /dev/null
@@ -1,7 +0,0 @@
----
-created: "2019-01-22T14:45:00.552379600+00:00"
-creator: [email protected]
-expression: kind_completions
-source: "crates\\ra_ide_api\\src\\completion\\completion_item.rs"
----
-[]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__param_completion_last_param.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__param_completion_last_param.snap
deleted file mode 100644
index cab77f5a2..000000000
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__param_completion_last_param.snap
+++ /dev/null
@@ -1,15 +0,0 @@
----
-created: "2019-02-18T09:22:23.949634602Z"
-creator: [email protected]
-source: crates/ra_ide_api/src/completion/completion_item.rs
-expression: kind_completions
----
-[
-    CompletionItem {
-        label: "file_id: FileId",
-        source_range: [98; 102),
-        delete: [98; 102),
-        insert: "file_id: FileId",
-        lookup: "file_id"
-    }
-]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__param_completion_nth_param.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__param_completion_nth_param.snap
deleted file mode 100644
index 8fbee160c..000000000
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__param_completion_nth_param.snap
+++ /dev/null
@@ -1,15 +0,0 @@
----
-created: "2019-02-18T09:22:23.949634355Z"
-creator: [email protected]
-source: crates/ra_ide_api/src/completion/completion_item.rs
-expression: kind_completions
----
-[
-    CompletionItem {
-        label: "file_id: FileId",
-        source_range: [98; 102),
-        delete: [98; 102),
-        insert: "file_id: FileId",
-        lookup: "file_id"
-    }
-]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__param_completion_trait_param.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__param_completion_trait_param.snap
deleted file mode 100644
index 76eeadb6d..000000000
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__param_completion_trait_param.snap
+++ /dev/null
@@ -1,15 +0,0 @@
----
-created: "2019-02-18T09:22:23.974417169Z"
-creator: [email protected]
-source: crates/ra_ide_api/src/completion/completion_item.rs
-expression: kind_completions
----
-[
-    CompletionItem {
-        label: "file_id: FileId",
-        source_range: [269; 273),
-        delete: [269; 273),
-        insert: "file_id: FileId",
-        lookup: "file_id"
-    }
-]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__return_type.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__return_type.snap
index 0738cf466..ff36df707 100644
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__return_type.snap
+++ b/crates/ra_ide_api/src/completion/snapshots/completion_item__return_type.snap
@@ -1,6 +1,6 @@
 ---
-created: "2019-02-18T09:22:24.182964414Z"
-creator: insta@0.6.2
+created: "2019-04-04T14:52:24.525395600Z"
+creator: insta@0.7.4
 source: crates/ra_ide_api/src/completion/completion_item.rs
 expression: kind_completions
 ---
@@ -18,6 +18,6 @@ expression: kind_completions
         delete: [47; 47),
         insert: "x()$0",
         kind: Function,
-        detail: "fn x() ->"
+        detail: "fn x()"
     }
 ]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion.snap
deleted file mode 100644
index 58271b873..000000000
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion.snap
+++ /dev/null
@@ -1,16 +0,0 @@
----
-created: "2019-02-18T09:22:23.939645902Z"
-creator: [email protected]
-source: crates/ra_ide_api/src/completion/completion_item.rs
-expression: kind_completions
----
-[
-    CompletionItem {
-        label: "the_field",
-        source_range: [85; 85),
-        delete: [85; 85),
-        insert: "the_field",
-        kind: Field,
-        detail: "u32"
-    }
-]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_autoderef.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_autoderef.snap
deleted file mode 100644
index b38867b81..000000000
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_autoderef.snap
+++ /dev/null
@@ -1,24 +0,0 @@
----
-created: "2019-02-18T09:22:23.940872916Z"
-creator: [email protected]
-source: crates/ra_ide_api/src/completion/completion_item.rs
-expression: kind_completions
----
-[
-    CompletionItem {
-        label: "foo",
-        source_range: [126; 126),
-        delete: [126; 126),
-        insert: "foo()$0",
-        kind: Method,
-        detail: "fn foo(&self)"
-    },
-    CompletionItem {
-        label: "the_field",
-        source_range: [126; 126),
-        delete: [126; 126),
-        insert: "the_field",
-        kind: Field,
-        detail: "(u32, i32)"
-    }
-]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_self.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_self.snap
deleted file mode 100644
index 8e5cab43e..000000000
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__struct_field_completion_self.snap
+++ /dev/null
@@ -1,27 +0,0 @@
----
-created: "2019-02-18T09:22:23.940872918Z"
-creator: [email protected]
-source: crates/ra_ide_api/src/completion/completion_item.rs
-expression: kind_completions
----
-[
-    CompletionItem {
-        label: "foo",
-        source_range: [187; 187),
-        delete: [187; 187),
-        insert: "foo()$0",
-        kind: Method,
-        detail: "fn foo(self)"
-    },
-    CompletionItem {
-        label: "the_field",
-        source_range: [187; 187),
-        delete: [187; 187),
-        insert: "the_field",
-        kind: Field,
-        detail: "(u32,)",
-        documentation: Documentation(
-            "This is the_field"
-        )
-    }
-]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__tuple_field_completion.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__tuple_field_completion.snap
deleted file mode 100644
index 3f2780621..000000000
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__tuple_field_completion.snap
+++ /dev/null
@@ -1,24 +0,0 @@
----
-created: "2019-02-18T09:22:23.939710971Z"
-creator: [email protected]
-source: crates/ra_ide_api/src/completion/completion_item.rs
-expression: kind_completions
----
-[
-    CompletionItem {
-        label: "0",
-        source_range: [75; 75),
-        delete: [75; 75),
-        insert: "0",
-        kind: Field,
-        detail: "i32"
-    },
-    CompletionItem {
-        label: "1",
-        source_range: [75; 75),
-        delete: [75; 75),
-        insert: "1",
-        kind: Field,
-        detail: "f64"
-    }
-]
diff --git a/crates/ra_ide_api/src/completion/snapshots/completion_item__tuple_field_inference.snap b/crates/ra_ide_api/src/completion/snapshots/completion_item__tuple_field_inference.snap
deleted file mode 100644
index 72c8973b8..000000000
--- a/crates/ra_ide_api/src/completion/snapshots/completion_item__tuple_field_inference.snap
+++ /dev/null
@@ -1,16 +0,0 @@
----
-created: "2019-04-05T23:00:18.283812700Z"
-creator: [email protected]
-source: crates/ra_ide_api/src/completion/completion_item.rs
-expression: kind_completions
----
-[
-    CompletionItem {
-        label: "blah",
-        source_range: [299; 300),
-        delete: [299; 300),
-        insert: "blah()$0",
-        kind: Method,
-        detail: "pub fn blah(&self)"
-    }
-]
diff --git a/crates/ra_ide_api/src/db.rs b/crates/ra_ide_api/src/db.rs
index ea4255d35..33d3903bb 100644
--- a/crates/ra_ide_api/src/db.rs
+++ b/crates/ra_ide_api/src/db.rs
@@ -20,7 +20,6 @@ use crate::{LineIndex, symbol_index::{self, SymbolsDatabase}};
 #[derive(Debug)]
 pub(crate) struct RootDatabase {
     runtime: salsa::Runtime<RootDatabase>,
-    interner: Arc<hir::HirInterner>,
     pub(crate) last_gc: time::Instant,
     pub(crate) last_gc_check: time::Instant,
 }
@@ -38,7 +37,6 @@ impl Default for RootDatabase {
     fn default() -> RootDatabase {
         let mut db = RootDatabase {
             runtime: salsa::Runtime::default(),
-            interner: Default::default(),
             last_gc: time::Instant::now(),
             last_gc_check: time::Instant::now(),
         };
@@ -53,19 +51,12 @@ impl salsa::ParallelDatabase for RootDatabase {
     fn snapshot(&self) -> salsa::Snapshot<RootDatabase> {
         salsa::Snapshot::new(RootDatabase {
             runtime: self.runtime.snapshot(self),
-            interner: Arc::clone(&self.interner),
             last_gc: self.last_gc.clone(),
             last_gc_check: self.last_gc_check.clone(),
         })
     }
 }
 
-impl AsRef<hir::HirInterner> for RootDatabase {
-    fn as_ref(&self) -> &hir::HirInterner {
-        &self.interner
-    }
-}
-
 #[salsa::query_group(LineIndexDatabaseStorage)]
 pub(crate) trait LineIndexDatabase: ra_db::SourceDatabase + CheckCanceled {
     fn line_index(&self, file_id: FileId) -> Arc<LineIndex>;
diff --git a/crates/ra_ide_api/src/display.rs b/crates/ra_ide_api/src/display.rs
new file mode 100644
index 000000000..1b06abf94
--- /dev/null
+++ b/crates/ra_ide_api/src/display.rs
@@ -0,0 +1,82 @@
+//! This module contains utilities for turning SyntaxNodes and HIR types
+//! into types that may be used to render in a UI.
+
+mod function_signature;
+mod navigation_target;
+mod structure;
+
+use crate::db::RootDatabase;
+use ra_syntax::{ast::{self, AstNode, TypeParamsOwner}, SyntaxKind::{ATTR, COMMENT}};
+
+pub use navigation_target::NavigationTarget;
+pub use structure::{StructureNode, file_structure};
+pub use function_signature::FunctionSignature;
+
+pub(crate) fn function_label(node: &ast::FnDef) -> String {
+    FunctionSignature::from(node).to_string()
+}
+
+pub(crate) fn const_label(node: &ast::ConstDef) -> String {
+    let label: String = node
+        .syntax()
+        .children_with_tokens()
+        .filter(|child| !(child.kind() == COMMENT || child.kind() == ATTR))
+        .map(|node| node.to_string())
+        .collect();
+
+    label.trim().to_owned()
+}
+
+pub(crate) fn type_label(node: &ast::TypeAliasDef) -> String {
+    let label: String = node
+        .syntax()
+        .children_with_tokens()
+        .filter(|child| !(child.kind() == COMMENT || child.kind() == ATTR))
+        .map(|node| node.to_string())
+        .collect();
+
+    label.trim().to_owned()
+}
+
+pub(crate) fn generic_parameters<N: TypeParamsOwner>(node: &N) -> Vec<String> {
+    let mut res = vec![];
+    if let Some(type_params) = node.type_param_list() {
+        res.extend(type_params.lifetime_params().map(|p| p.syntax().text().to_string()));
+        res.extend(type_params.type_params().map(|p| p.syntax().text().to_string()));
+    }
+    res
+}
+
+pub(crate) fn where_predicates<N: TypeParamsOwner>(node: &N) -> Vec<String> {
+    let mut res = vec![];
+    if let Some(clause) = node.where_clause() {
+        res.extend(clause.predicates().map(|p| p.syntax().text().to_string()));
+    }
+    res
+}
+
+pub(crate) fn rust_code_markup<CODE: AsRef<str>>(val: CODE) -> String {
+    rust_code_markup_with_doc::<_, &str>(val, None)
+}
+
+pub(crate) fn rust_code_markup_with_doc<CODE, DOC>(val: CODE, doc: Option<DOC>) -> String
+where
+    CODE: AsRef<str>,
+    DOC: AsRef<str>,
+{
+    if let Some(doc) = doc {
+        format!("```rust\n{}\n```\n\n{}", val.as_ref(), doc.as_ref())
+    } else {
+        format!("```rust\n{}\n```", val.as_ref())
+    }
+}
+
+// FIXME: this should not really use navigation target. Rather, approximately
+// resolved symbol should return a `DefId`.
+pub(crate) fn doc_text_for(db: &RootDatabase, nav: NavigationTarget) -> Option<String> {
+    match (nav.description(db), nav.docs(db)) {
+        (Some(desc), docs) => Some(rust_code_markup_with_doc(desc, docs)),
+        (None, Some(docs)) => Some(docs),
+        _ => None,
+    }
+}
diff --git a/crates/ra_ide_api/src/display/function_signature.rs b/crates/ra_ide_api/src/display/function_signature.rs
new file mode 100644
index 000000000..d09950bce
--- /dev/null
+++ b/crates/ra_ide_api/src/display/function_signature.rs
@@ -0,0 +1,101 @@
+use super::{where_predicates, generic_parameters};
+use crate::db;
+use std::fmt::{self, Display};
+use join_to_string::join;
+use ra_syntax::ast::{self, AstNode, NameOwner, VisibilityOwner};
+use std::convert::From;
+use hir::{Docs, Documentation};
+
+/// Contains information about a function signature
+#[derive(Debug)]
+pub struct FunctionSignature {
+    /// Optional visibility
+    pub visibility: Option<String>,
+    /// Name of the function
+    pub name: Option<String>,
+    /// Documentation for the function
+    pub doc: Option<Documentation>,
+    /// Generic parameters
+    pub generic_parameters: Vec<String>,
+    /// Parameters of the function
+    pub parameters: Vec<String>,
+    /// Optional return type
+    pub ret_type: Option<String>,
+    /// Where predicates
+    pub where_predicates: Vec<String>,
+}
+
+impl FunctionSignature {
+    pub(crate) fn with_doc_opt(mut self, doc: Option<Documentation>) -> Self {
+        self.doc = doc;
+        self
+    }
+
+    pub(crate) fn from_hir(db: &db::RootDatabase, function: hir::Function) -> Self {
+        let doc = function.docs(db);
+        let (_, ast_node) = function.source(db);
+        FunctionSignature::from(&*ast_node).with_doc_opt(doc)
+    }
+}
+
+impl From<&'_ ast::FnDef> for FunctionSignature {
+    fn from(node: &ast::FnDef) -> FunctionSignature {
+        fn param_list(node: &ast::FnDef) -> Vec<String> {
+            let mut res = vec![];
+            if let Some(param_list) = node.param_list() {
+                if let Some(self_param) = param_list.self_param() {
+                    res.push(self_param.syntax().text().to_string())
+                }
+
+                res.extend(param_list.params().map(|param| param.syntax().text().to_string()));
+            }
+            res
+        }
+
+        FunctionSignature {
+            visibility: node.visibility().map(|n| n.syntax().text().to_string()),
+            name: node.name().map(|n| n.text().to_string()),
+            ret_type: node
+                .ret_type()
+                .and_then(|r| r.type_ref())
+                .map(|n| n.syntax().text().to_string()),
+            parameters: param_list(node),
+            generic_parameters: generic_parameters(node),
+            where_predicates: where_predicates(node),
+            // docs are processed separately
+            doc: None,
+        }
+    }
+}
+
+impl Display for FunctionSignature {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        if let Some(t) = &self.visibility {
+            write!(f, "{} ", t)?;
+        }
+
+        if let Some(name) = &self.name {
+            write!(f, "fn {}", name)?;
+        }
+
+        if !self.generic_parameters.is_empty() {
+            join(self.generic_parameters.iter())
+                .separator(", ")
+                .surround_with("<", ">")
+                .to_fmt(f)?;
+        }
+
+        join(self.parameters.iter()).separator(", ").surround_with("(", ")").to_fmt(f)?;
+
+        if let Some(t) = &self.ret_type {
+            write!(f, " -> {}", t)?;
+        }
+
+        if !self.where_predicates.is_empty() {
+            write!(f, "\nwhere ")?;
+            join(self.where_predicates.iter()).separator(",\n      ").to_fmt(f)?;
+        }
+
+        Ok(())
+    }
+}
diff --git a/crates/ra_ide_api/src/navigation_target.rs b/crates/ra_ide_api/src/display/navigation_target.rs
index f6d7f3192..84645287d 100644
--- a/crates/ra_ide_api/src/navigation_target.rs
+++ b/crates/ra_ide_api/src/display/navigation_target.rs
@@ -1,9 +1,11 @@
-use ra_db::FileId;
+use ra_db::{FileId, SourceDatabase};
 use ra_syntax::{
-    SyntaxNode, SyntaxNodePtr, AstNode, SmolStr, TextRange, ast,
+    SyntaxNode, AstNode, SmolStr, TextRange, TreeArc, AstPtr,
     SyntaxKind::{self, NAME},
+    ast::{self, NameOwner, VisibilityOwner, TypeAscriptionOwner},
+    algo::visit::{visitor, Visitor},
 };
-use hir::{ModuleSource, FieldSource, Name, ImplItem};
+use hir::{ModuleSource, FieldSource, ImplItem, Either};
 
 use crate::{FileSymbol, db::RootDatabase};
 
@@ -72,15 +74,25 @@ impl NavigationTarget {
         }
     }
 
-    pub(crate) fn from_scope_entry(
+    pub(crate) fn from_pat(
+        db: &RootDatabase,
         file_id: FileId,
-        name: Name,
-        ptr: SyntaxNodePtr,
+        pat: Either<AstPtr<ast::Pat>, AstPtr<ast::SelfParam>>,
     ) -> NavigationTarget {
+        let file = db.parse(file_id);
+        let (name, full_range) = match pat {
+            Either::A(pat) => match pat.to_node(&file).kind() {
+                ast::PatKind::BindPat(pat) => {
+                    return NavigationTarget::from_bind_pat(file_id, &pat)
+                }
+                _ => ("_".into(), pat.syntax_node_ptr().range()),
+            },
+            Either::B(slf) => ("self".into(), slf.syntax_node_ptr().range()),
+        };
         NavigationTarget {
             file_id,
-            name: name.to_string().into(),
-            full_range: ptr.range(),
+            name,
+            full_range,
             focus_range: None,
             kind: NAME,
             container_name: None,
@@ -227,6 +239,7 @@ impl NavigationTarget {
 
     /// Allows `NavigationTarget` to be created from a `NameOwner`
     pub(crate) fn from_named(file_id: FileId, node: &impl ast::NameOwner) -> NavigationTarget {
+        //FIXME: use `_` instead of empty string
         let name = node.name().map(|it| it.text().clone()).unwrap_or_default();
         let focus_range = node.name().map(|it| it.syntax().range());
         NavigationTarget::from_syntax(file_id, name, focus_range, node.syntax())
@@ -248,4 +261,80 @@ impl NavigationTarget {
             container_name: None,
         }
     }
+
+    pub(crate) fn node(&self, db: &RootDatabase) -> Option<TreeArc<SyntaxNode>> {
+        let source_file = db.parse(self.file_id());
+        let source_file = source_file.syntax();
+        let node = source_file
+            .descendants()
+            .find(|node| node.kind() == self.kind() && node.range() == self.full_range())?
+            .to_owned();
+        Some(node)
+    }
+
+    pub(crate) fn docs(&self, db: &RootDatabase) -> Option<String> {
+        let node = self.node(db)?;
+        fn doc_comments<N: ast::DocCommentsOwner>(node: &N) -> Option<String> {
+            node.doc_comment_text()
+        }
+
+        visitor()
+            .visit(doc_comments::<ast::FnDef>)
+            .visit(doc_comments::<ast::StructDef>)
+            .visit(doc_comments::<ast::EnumDef>)
+            .visit(doc_comments::<ast::TraitDef>)
+            .visit(doc_comments::<ast::Module>)
+            .visit(doc_comments::<ast::TypeAliasDef>)
+            .visit(doc_comments::<ast::ConstDef>)
+            .visit(doc_comments::<ast::StaticDef>)
+            .visit(doc_comments::<ast::NamedFieldDef>)
+            .visit(doc_comments::<ast::EnumVariant>)
+            .accept(&node)?
+    }
+
+    /// Get a description of this node.
+    ///
+    /// e.g. `struct Name`, `enum Name`, `fn Name`
+    pub(crate) fn description(&self, db: &RootDatabase) -> Option<String> {
+        // FIXME: After type inference is done, add type information to improve the output
+        let node = self.node(db)?;
+
+        fn visit_ascribed_node<T>(node: &T, prefix: &str) -> Option<String>
+        where
+            T: NameOwner + VisibilityOwner + TypeAscriptionOwner,
+        {
+            let mut string = visit_node(node, prefix)?;
+
+            if let Some(type_ref) = node.ascribed_type() {
+                string.push_str(": ");
+                type_ref.syntax().text().push_to(&mut string);
+            }
+
+            Some(string)
+        }
+
+        fn visit_node<T>(node: &T, label: &str) -> Option<String>
+        where
+            T: NameOwner + VisibilityOwner,
+        {
+            let mut string =
+                node.visibility().map(|v| format!("{} ", v.syntax().text())).unwrap_or_default();
+            string.push_str(label);
+            string.push_str(node.name()?.text().as_str());
+            Some(string)
+        }
+
+        visitor()
+            .visit(|node: &ast::FnDef| Some(crate::display::function_label(node)))
+            .visit(|node: &ast::StructDef| visit_node(node, "struct "))
+            .visit(|node: &ast::EnumDef| visit_node(node, "enum "))
+            .visit(|node: &ast::TraitDef| visit_node(node, "trait "))
+            .visit(|node: &ast::Module| visit_node(node, "mod "))
+            .visit(|node: &ast::TypeAliasDef| visit_node(node, "type "))
+            .visit(|node: &ast::ConstDef| visit_ascribed_node(node, "const "))
+            .visit(|node: &ast::StaticDef| visit_ascribed_node(node, "static "))
+            .visit(|node: &ast::NamedFieldDef| visit_ascribed_node(node, ""))
+            .visit(|node: &ast::EnumVariant| Some(node.name()?.text().to_string()))
+            .accept(&node)?
+    }
 }
diff --git a/crates/ra_ide_api/src/snapshots/tests__file_structure.snap b/crates/ra_ide_api/src/display/snapshots/tests__file_structure.snap
index 2efa8e22c..32dd99484 100644
--- a/crates/ra_ide_api/src/snapshots/tests__file_structure.snap
+++ b/crates/ra_ide_api/src/display/snapshots/tests__file_structure.snap
@@ -1,7 +1,7 @@
 ---
-created: "2019-02-05T22:03:50.763530100Z"
-creator: insta@0.6.1
-source: crates/ra_ide_api/src/structure.rs
+created: "2019-04-08T09:44:50.196004400Z"
+creator: insta@0.7.4
+source: crates/ra_ide_api/src/display/structure.rs
 expression: structure
 ---
 [
diff --git a/crates/ra_ide_api/src/structure.rs b/crates/ra_ide_api/src/display/structure.rs
index ec2c9bbc6..ec2c9bbc6 100644
--- a/crates/ra_ide_api/src/structure.rs
+++ b/crates/ra_ide_api/src/display/structure.rs
diff --git a/crates/ra_ide_api/src/goto_definition.rs b/crates/ra_ide_api/src/goto_definition.rs
index 660b43cfa..40a2bd148 100644
--- a/crates/ra_ide_api/src/goto_definition.rs
+++ b/crates/ra_ide_api/src/goto_definition.rs
@@ -5,7 +5,6 @@ use ra_syntax::{
     SyntaxNode,
 };
 use test_utils::tested_by;
-use hir::Resolution;
 
 use crate::{FilePosition, NavigationTarget, db::RootDatabase, RangeInfo};
 
@@ -48,126 +47,70 @@ pub(crate) fn reference_definition(
 ) -> ReferenceResult {
     use self::ReferenceResult::*;
 
-    let function = hir::source_binder::function_from_child_node(db, file_id, name_ref.syntax());
-
-    if let Some(function) = function {
-        // Check if it is a method
-        if let Some(method_call) = name_ref.syntax().parent().and_then(ast::MethodCallExpr::cast) {
-            tested_by!(goto_definition_works_for_methods);
-            let infer_result = function.infer(db);
-            let source_map = function.body_source_map(db);
-            let expr = ast::Expr::cast(method_call.syntax()).unwrap();
-            if let Some(func) =
-                source_map.node_expr(expr).and_then(|it| infer_result.method_resolution(it))
-            {
-                return Exact(NavigationTarget::from_function(db, func));
-            };
-        }
-        // It could also be a field access
-        if let Some(field_expr) = name_ref.syntax().parent().and_then(ast::FieldExpr::cast) {
-            tested_by!(goto_definition_works_for_fields);
-            let infer_result = function.infer(db);
-            let source_map = function.body_source_map(db);
-            let expr = ast::Expr::cast(field_expr.syntax()).unwrap();
-            if let Some(field) =
-                source_map.node_expr(expr).and_then(|it| infer_result.field_resolution(it))
-            {
-                return Exact(NavigationTarget::from_field(db, field));
-            };
-        }
+    let analyzer = hir::SourceAnalyzer::new(db, file_id, name_ref.syntax(), None);
 
-        // It could also be a named field
-        if let Some(field_expr) = name_ref.syntax().parent().and_then(ast::NamedField::cast) {
-            tested_by!(goto_definition_works_for_named_fields);
+    // Special cases:
 
-            let infer_result = function.infer(db);
-            let source_map = function.body_source_map(db);
+    // Check if it is a method
+    if let Some(method_call) = name_ref.syntax().parent().and_then(ast::MethodCallExpr::cast) {
+        tested_by!(goto_definition_works_for_methods);
+        if let Some(func) = analyzer.resolve_method_call(method_call) {
+            return Exact(NavigationTarget::from_function(db, func));
+        }
+    }
+    // It could also be a field access
+    if let Some(field_expr) = name_ref.syntax().parent().and_then(ast::FieldExpr::cast) {
+        tested_by!(goto_definition_works_for_fields);
+        if let Some(field) = analyzer.resolve_field(field_expr) {
+            return Exact(NavigationTarget::from_field(db, field));
+        };
+    }
 
-            let struct_lit = field_expr.syntax().ancestors().find_map(ast::StructLit::cast);
+    // It could also be a named field
+    if let Some(field_expr) = name_ref.syntax().parent().and_then(ast::NamedField::cast) {
+        tested_by!(goto_definition_works_for_named_fields);
 
-            if let Some(expr) = struct_lit.and_then(|lit| source_map.node_expr(lit.into())) {
-                let ty = infer_result[expr].clone();
-                if let Some((hir::AdtDef::Struct(s), _)) = ty.as_adt() {
-                    let hir_path = hir::Path::from_name_ref(name_ref);
-                    let hir_name = hir_path.as_ident().unwrap();
+        let struct_lit = field_expr.syntax().ancestors().find_map(ast::StructLit::cast);
 
-                    if let Some(field) = s.field(db, hir_name) {
-                        return Exact(NavigationTarget::from_field(db, field));
-                    }
+        if let Some(ty) = struct_lit.and_then(|lit| analyzer.type_of(db, lit.into())) {
+            if let Some((hir::AdtDef::Struct(s), _)) = ty.as_adt() {
+                let hir_path = hir::Path::from_name_ref(name_ref);
+                let hir_name = hir_path.as_ident().unwrap();
+
+                if let Some(field) = s.field(db, hir_name) {
+                    return Exact(NavigationTarget::from_field(db, field));
                 }
             }
         }
     }
 
-    // Try name resolution
-    let resolver = hir::source_binder::resolver_for_node(db, file_id, name_ref.syntax());
-    if let Some(path) =
-        name_ref.syntax().ancestors().find_map(ast::Path::cast).and_then(hir::Path::from_ast)
-    {
-        let resolved = resolver.resolve_path(db, &path);
-        match resolved.clone().take_types().or_else(|| resolved.take_values()) {
-            Some(Resolution::Def(def)) => return Exact(NavigationTarget::from_def(db, def)),
-            Some(Resolution::LocalBinding(pat)) => {
-                let body = resolver.body().expect("no body for local binding");
-                let source_map = body.owner().body_source_map(db);
-                let ptr = source_map.pat_syntax(pat).expect("pattern not found in syntax mapping");
-                let name =
-                    path.as_ident().cloned().expect("local binding from a multi-segment path");
-                let nav = NavigationTarget::from_scope_entry(file_id, name, ptr);
-                return Exact(nav);
-            }
-            Some(Resolution::GenericParam(..)) => {
-                // FIXME: go to the generic param def
-            }
-            Some(Resolution::SelfType(impl_block)) => {
-                let ty = impl_block.target_ty(db);
-
-                if let Some((def_id, _)) = ty.as_adt() {
-                    return Exact(NavigationTarget::from_adt_def(db, def_id));
+    // General case, a path or a local:
+    if let Some(path) = name_ref.syntax().ancestors().find_map(ast::Path::cast) {
+        if let Some(resolved) = analyzer.resolve_path(db, path) {
+            match resolved {
+                hir::PathResolution::Def(def) => return Exact(NavigationTarget::from_def(db, def)),
+                hir::PathResolution::LocalBinding(pat) => {
+                    let nav = NavigationTarget::from_pat(db, file_id, pat);
+                    return Exact(nav);
                 }
-            }
-            None => {
-                // If we failed to resolve then check associated items
-                if let Some(function) = function {
-                    // Resolve associated item for path expressions
-                    if let Some(path_expr) =
-                        name_ref.syntax().ancestors().find_map(ast::PathExpr::cast)
-                    {
-                        let infer_result = function.infer(db);
-                        let source_map = function.body_source_map(db);
-
-                        if let Some(expr) = ast::Expr::cast(path_expr.syntax()) {
-                            if let Some(res) = source_map
-                                .node_expr(expr)
-                                .and_then(|it| infer_result.assoc_resolutions_for_expr(it.into()))
-                            {
-                                return Exact(NavigationTarget::from_impl_item(db, res));
-                            }
-                        }
-                    }
+                hir::PathResolution::GenericParam(..) => {
+                    // FIXME: go to the generic param def
+                }
+                hir::PathResolution::SelfType(impl_block) => {
+                    let ty = impl_block.target_ty(db);
 
-                    // Resolve associated item for path patterns
-                    if let Some(path_pat) =
-                        name_ref.syntax().ancestors().find_map(ast::PathPat::cast)
-                    {
-                        let infer_result = function.infer(db);
-                        let source_map = function.body_source_map(db);
-
-                        let pat: &ast::Pat = path_pat.into();
-
-                        if let Some(res) = source_map
-                            .node_pat(pat)
-                            .and_then(|it| infer_result.assoc_resolutions_for_pat(it.into()))
-                        {
-                            return Exact(NavigationTarget::from_impl_item(db, res));
-                        }
+                    if let Some((def_id, _)) = ty.as_adt() {
+                        return Exact(NavigationTarget::from_adt_def(db, def_id));
                     }
                 }
+                hir::PathResolution::AssocItem(assoc) => {
+                    return Exact(NavigationTarget::from_impl_item(db, assoc));
+                }
             }
         }
     }
 
-    // If that fails try the index based approach.
+    // Fallback index based approach:
     let navs = crate::symbol_index::index_resolve(db, name_ref)
         .into_iter()
         .map(NavigationTarget::from_symbol)
diff --git a/crates/ra_ide_api/src/hover.rs b/crates/ra_ide_api/src/hover.rs
index bfa7cd67a..397b56786 100644
--- a/crates/ra_ide_api/src/hover.rs
+++ b/crates/ra_ide_api/src/hover.rs
@@ -1,11 +1,11 @@
 use ra_db::SourceDatabase;
 use ra_syntax::{
-    AstNode, SyntaxNode, TreeArc, ast::{self, NameOwner, VisibilityOwner, TypeAscriptionOwner},
-    algo::{find_covering_element, find_node_at_offset, find_token_at_offset, visit::{visitor, Visitor}},
+    AstNode, ast,
+    algo::{find_covering_element, find_node_at_offset, find_token_at_offset},
 };
 use hir::HirDisplay;
 
-use crate::{db::RootDatabase, RangeInfo, FilePosition, FileRange, NavigationTarget};
+use crate::{db::RootDatabase, RangeInfo, FilePosition, FileRange, display::{rust_code_markup, doc_text_for}};
 
 /// Contains the results when hovering over an item
 #[derive(Debug, Clone)]
@@ -132,121 +132,15 @@ pub(crate) fn type_of(db: &RootDatabase, frange: FileRange) -> Option<String> {
         .ancestors()
         .take_while(|it| it.range() == leaf_node.range())
         .find(|&it| ast::Expr::cast(it).is_some() || ast::Pat::cast(it).is_some())?;
-    let parent_fn = node.ancestors().find_map(ast::FnDef::cast)?;
-    let function = hir::source_binder::function_from_source(db, frange.file_id, parent_fn)?;
-    let infer = function.infer(db);
-    let source_map = function.body_source_map(db);
-    if let Some(expr) = ast::Expr::cast(node).and_then(|e| source_map.node_expr(e)) {
-        Some(infer[expr].display(db).to_string())
-    } else if let Some(pat) = ast::Pat::cast(node).and_then(|p| source_map.node_pat(p)) {
-        Some(infer[pat].display(db).to_string())
+    let analyzer = hir::SourceAnalyzer::new(db, frange.file_id, node, None);
+    let ty = if let Some(ty) = ast::Expr::cast(node).and_then(|e| analyzer.type_of(db, e)) {
+        ty
+    } else if let Some(ty) = ast::Pat::cast(node).and_then(|p| analyzer.type_of_pat(db, p)) {
+        ty
     } else {
-        None
-    }
-}
-
-fn rust_code_markup<CODE: AsRef<str>>(val: CODE) -> String {
-    rust_code_markup_with_doc::<_, &str>(val, None)
-}
-
-fn rust_code_markup_with_doc<CODE, DOC>(val: CODE, doc: Option<DOC>) -> String
-where
-    CODE: AsRef<str>,
-    DOC: AsRef<str>,
-{
-    if let Some(doc) = doc {
-        format!("```rust\n{}\n```\n\n{}", val.as_ref(), doc.as_ref())
-    } else {
-        format!("```rust\n{}\n```", val.as_ref())
-    }
-}
-
-// FIXME: this should not really use navigation target. Rather, approximately
-// resolved symbol should return a `DefId`.
-fn doc_text_for(db: &RootDatabase, nav: NavigationTarget) -> Option<String> {
-    match (nav.description(db), nav.docs(db)) {
-        (Some(desc), docs) => Some(rust_code_markup_with_doc(desc, docs)),
-        (None, Some(docs)) => Some(docs),
-        _ => None,
-    }
-}
-
-impl NavigationTarget {
-    fn node(&self, db: &RootDatabase) -> Option<TreeArc<SyntaxNode>> {
-        let source_file = db.parse(self.file_id());
-        let source_file = source_file.syntax();
-        let node = source_file
-            .descendants()
-            .find(|node| node.kind() == self.kind() && node.range() == self.full_range())?
-            .to_owned();
-        Some(node)
-    }
-
-    fn docs(&self, db: &RootDatabase) -> Option<String> {
-        let node = self.node(db)?;
-        fn doc_comments<N: ast::DocCommentsOwner>(node: &N) -> Option<String> {
-            node.doc_comment_text()
-        }
-
-        visitor()
-            .visit(doc_comments::<ast::FnDef>)
-            .visit(doc_comments::<ast::StructDef>)
-            .visit(doc_comments::<ast::EnumDef>)
-            .visit(doc_comments::<ast::TraitDef>)
-            .visit(doc_comments::<ast::Module>)
-            .visit(doc_comments::<ast::TypeAliasDef>)
-            .visit(doc_comments::<ast::ConstDef>)
-            .visit(doc_comments::<ast::StaticDef>)
-            .visit(doc_comments::<ast::NamedFieldDef>)
-            .visit(doc_comments::<ast::EnumVariant>)
-            .accept(&node)?
-    }
-
-    /// Get a description of this node.
-    ///
-    /// e.g. `struct Name`, `enum Name`, `fn Name`
-    fn description(&self, db: &RootDatabase) -> Option<String> {
-        // FIXME: After type inference is done, add type information to improve the output
-        let node = self.node(db)?;
-
-        fn visit_ascribed_node<T>(node: &T, prefix: &str) -> Option<String>
-        where
-            T: NameOwner + VisibilityOwner + TypeAscriptionOwner,
-        {
-            let mut string = visit_node(node, prefix)?;
-
-            if let Some(type_ref) = node.ascribed_type() {
-                string.push_str(": ");
-                type_ref.syntax().text().push_to(&mut string);
-            }
-
-            Some(string)
-        }
-
-        fn visit_node<T>(node: &T, label: &str) -> Option<String>
-        where
-            T: NameOwner + VisibilityOwner,
-        {
-            let mut string =
-                node.visibility().map(|v| format!("{} ", v.syntax().text())).unwrap_or_default();
-            string.push_str(label);
-            string.push_str(node.name()?.text().as_str());
-            Some(string)
-        }
-
-        visitor()
-            .visit(crate::completion::function_label)
-            .visit(|node: &ast::StructDef| visit_node(node, "struct "))
-            .visit(|node: &ast::EnumDef| visit_node(node, "enum "))
-            .visit(|node: &ast::TraitDef| visit_node(node, "trait "))
-            .visit(|node: &ast::Module| visit_node(node, "mod "))
-            .visit(|node: &ast::TypeAliasDef| visit_node(node, "type "))
-            .visit(|node: &ast::ConstDef| visit_ascribed_node(node, "const "))
-            .visit(|node: &ast::StaticDef| visit_ascribed_node(node, "static "))
-            .visit(|node: &ast::NamedFieldDef| visit_ascribed_node(node, ""))
-            .visit(|node: &ast::EnumVariant| Some(node.name()?.text().to_string()))
-            .accept(&node)?
-    }
+        return None;
+    };
+    Some(ty.display(db).to_string())
 }
 
 #[cfg(test)]
diff --git a/crates/ra_ide_api/src/lib.rs b/crates/ra_ide_api/src/lib.rs
index 9063f78a9..d25795adc 100644
--- a/crates/ra_ide_api/src/lib.rs
+++ b/crates/ra_ide_api/src/lib.rs
@@ -13,7 +13,6 @@
 mod db;
 pub mod mock_analysis;
 mod symbol_index;
-mod navigation_target;
 mod change;
 
 mod status;
@@ -34,9 +33,9 @@ mod folding_ranges;
 mod line_index;
 mod line_index_utils;
 mod join_lines;
-mod structure;
 mod typing;
 mod matching_brace;
+mod display;
 
 #[cfg(test)]
 mod marks;
@@ -62,7 +61,6 @@ pub use crate::{
     change::{AnalysisChange, LibraryData},
     completion::{CompletionItem, CompletionItemKind, InsertTextFormat},
     runnables::{Runnable, RunnableKind},
-    navigation_target::NavigationTarget,
     references::ReferenceSearchResult,
     assists::{Assist, AssistId},
     hover::{HoverResult},
@@ -70,8 +68,8 @@ pub use crate::{
     line_index_utils::translate_offset_with_edit,
     folding_ranges::{Fold, FoldKind},
     syntax_highlighting::HighlightedRange,
-    structure::{StructureNode, file_structure},
     diagnostics::Severity,
+    display::{FunctionSignature, NavigationTarget, StructureNode, file_structure},
 };
 
 pub use ra_db::{
@@ -243,9 +241,7 @@ impl<T> RangeInfo<T> {
 
 #[derive(Debug)]
 pub struct CallInfo {
-    pub label: String,
-    pub doc: Option<Documentation>,
-    pub parameters: Vec<String>,
+    pub signature: FunctionSignature,
     pub active_parameter: Option<usize>,
 }
 
@@ -387,7 +383,7 @@ impl Analysis {
     /// file outline.
     pub fn file_structure(&self, file_id: FileId) -> Vec<StructureNode> {
         let file = self.db.parse(file_id);
-        structure::file_structure(&file)
+        file_structure(&file)
     }
 
     /// Returns the set of folding ranges.
diff --git a/crates/ra_ide_api/src/references.rs b/crates/ra_ide_api/src/references.rs
index 20bbf11a3..9f655d83c 100644
--- a/crates/ra_ide_api/src/references.rs
+++ b/crates/ra_ide_api/src/references.rs
@@ -1,5 +1,5 @@
 use relative_path::{RelativePath, RelativePathBuf};
-use hir::{ModuleSource, source_binder};
+use hir::{ModuleSource, source_binder, Either};
 use ra_db::{SourceDatabase};
 use ra_syntax::{
     AstNode, SyntaxNode, SourceFile,
@@ -61,11 +61,10 @@ pub(crate) fn find_all_refs(
     position: FilePosition,
 ) -> Option<ReferenceSearchResult> {
     let file = db.parse(position.file_id);
-    let (binding, descr) = find_binding(db, &file, position)?;
+    let (binding, analyzer) = find_binding(db, &file, position)?;
     let declaration = NavigationTarget::from_bind_pat(position.file_id, binding);
 
-    let references = descr
-        .scopes(db)
+    let references = analyzer
         .find_all_refs(binding)
         .into_iter()
         .map(move |ref_desc| FileRange { file_id: position.file_id, range: ref_desc.range })
@@ -77,21 +76,21 @@ pub(crate) fn find_all_refs(
         db: &RootDatabase,
         source_file: &'a SourceFile,
         position: FilePosition,
-    ) -> Option<(&'a ast::BindPat, hir::Function)> {
+    ) -> Option<(&'a ast::BindPat, hir::SourceAnalyzer)> {
         let syntax = source_file.syntax();
         if let Some(binding) = find_node_at_offset::<ast::BindPat>(syntax, position.offset) {
-            let descr =
-                source_binder::function_from_child_node(db, position.file_id, binding.syntax())?;
-            return Some((binding, descr));
+            let analyzer = hir::SourceAnalyzer::new(db, position.file_id, binding.syntax(), None);
+            return Some((binding, analyzer));
         };
         let name_ref = find_node_at_offset::<ast::NameRef>(syntax, position.offset)?;
-        let descr =
-            source_binder::function_from_child_node(db, position.file_id, name_ref.syntax())?;
-        let scope = descr.scopes(db);
-        let resolved = scope.resolve_local_name(name_ref)?;
-        let resolved = resolved.ptr().to_node(source_file);
-        let binding = find_node_at_offset::<ast::BindPat>(syntax, resolved.range().end())?;
-        Some((binding, descr))
+        let analyzer = hir::SourceAnalyzer::new(db, position.file_id, name_ref.syntax(), None);
+        let resolved = analyzer.resolve_local_name(name_ref)?;
+        if let Either::A(ptr) = resolved.ptr() {
+            if let ast::PatKind::BindPat(binding) = ptr.to_node(source_file).kind() {
+                return Some((binding, analyzer));
+            }
+        }
+        None
     }
 }
 
diff --git a/crates/ra_ide_api/src/runnables.rs b/crates/ra_ide_api/src/runnables.rs
index 2395930f0..3969076a8 100644
--- a/crates/ra_ide_api/src/runnables.rs
+++ b/crates/ra_ide_api/src/runnables.rs
@@ -65,7 +65,6 @@ fn runnable_mod(db: &RootDatabase, file_id: FileId, module: &ast::Module) -> Opt
     let range = module.syntax().range();
     let module = hir::source_binder::module_from_child_node(db, file_id, module.syntax())?;
 
-    // FIXME: thread cancellation instead of `.ok`ing
     let path = module.path_to_root(db).into_iter().rev().filter_map(|it| it.name(db)).join("::");
     Some(Runnable { range, kind: RunnableKind::TestMod { path } })
 }
diff --git a/crates/ra_ide_api/src/status.rs b/crates/ra_ide_api/src/status.rs
index e0fc1c123..d99a4e750 100644
--- a/crates/ra_ide_api/src/status.rs
+++ b/crates/ra_ide_api/src/status.rs
@@ -23,16 +23,11 @@ pub(crate) fn status(db: &RootDatabase) -> String {
     let files_stats = db.query(FileTextQuery).entries::<FilesStats>();
     let syntax_tree_stats = syntax_tree_stats(db);
     let symbols_stats = db.query(LibrarySymbolsQuery).entries::<LibrarySymbolsStats>();
-    let n_defs = {
-        let interner: &hir::HirInterner = db.as_ref();
-        interner.len()
-    };
     format!(
-        "{}\n{}\n{}\n{} defs\n\nmemory:\n{}\ngc {:?} seconds ago",
+        "{}\n{}\n{}\n\n\nmemory:\n{}\ngc {:?} seconds ago",
         files_stats,
         symbols_stats,
         syntax_tree_stats,
-        n_defs,
         MemoryStats::current(),
         db.last_gc.elapsed().as_secs(),
     )
diff --git a/crates/ra_ide_api/src/symbol_index.rs b/crates/ra_ide_api/src/symbol_index.rs
index 0eadc4e71..914d3fc71 100644
--- a/crates/ra_ide_api/src/symbol_index.rs
+++ b/crates/ra_ide_api/src/symbol_index.rs
@@ -275,7 +275,7 @@ fn to_file_symbol(node: &SyntaxNode, file_id: FileId) -> Option<FileSymbol> {
 mod tests {
     use ra_syntax::SmolStr;
     use crate::{
-        navigation_target::NavigationTarget,
+        display::NavigationTarget,
         mock_analysis::single_file,
         Query,
 };