15 files changed, 712 insertions, 198 deletions

diff --git a/crates/ra_analysis/src/completion.rs b/crates/ra_analysis/src/completion.rs
index 0141d132e..869ab5afb 100644
--- a/crates/ra_analysis/src/completion.rs
+++ b/crates/ra_analysis/src/completion.rs
@@ -1,14 +1,15 @@
 use ra_editor::{CompletionItem, find_node_at_offset};
 use ra_syntax::{
     AtomEdit, File, TextUnit, AstNode,
-    ast::{self, ModuleItemOwner, AstChildren},
+    ast,
 };
 
 use crate::{
     FileId, Cancelable,
     input::FilesDatabase,
     db::{self, SyntaxDatabase},
-    descriptors::module::{ModulesDatabase, ModuleTree, ModuleId, scope::ModuleScope},
+    descriptors::DescriptorDatabase,
+    descriptors::module::{ModuleTree, ModuleId},
 };
 
 pub(crate) fn resolve_based_completion(db: &db::RootDatabase, file_id: FileId, offset: TextUnit) -> Cancelable<Option<Vec<CompletionItem>>> {
diff --git a/crates/ra_analysis/src/db.rs b/crates/ra_analysis/src/db.rs
index e7a5d5e2f..fe6587f20 100644
--- a/crates/ra_analysis/src/db.rs
+++ b/crates/ra_analysis/src/db.rs
@@ -9,7 +9,10 @@ use salsa;
 use crate::{
     db,
     Cancelable, Canceled,
-    descriptors::module::{SubmodulesQuery, ModuleTreeQuery, ModulesDatabase, ModuleScopeQuery},
+    descriptors::{
+        DescriptorDatabase, SubmodulesQuery, ModuleTreeQuery, ModuleScopeQuery,
+        FnSyntaxQuery, FnScopesQuery
+    },
     symbol_index::SymbolIndex,
     syntax_ptr::{SyntaxPtrDatabase, ResolveSyntaxPtrQuery},
     FileId,
@@ -63,10 +66,12 @@ salsa::database_storage! {
             fn file_lines() for FileLinesQuery;
             fn file_symbols() for FileSymbolsQuery;
         }
-        impl ModulesDatabase {
+        impl DescriptorDatabase {
             fn module_tree() for ModuleTreeQuery;
             fn module_descriptor() for SubmodulesQuery;
             fn module_scope() for ModuleScopeQuery;
+            fn fn_syntax() for FnSyntaxQuery;
+            fn fn_scopes() for FnScopesQuery;
         }
         impl SyntaxPtrDatabase {
             fn resolve_syntax_ptr() for ResolveSyntaxPtrQuery;
diff --git a/crates/ra_analysis/src/descriptors/function/imp.rs b/crates/ra_analysis/src/descriptors/function/imp.rs
new file mode 100644
index 000000000..0a006f733
--- /dev/null
+++ b/crates/ra_analysis/src/descriptors/function/imp.rs
@@ -0,0 +1,26 @@
+use std::sync::Arc;
+
+use ra_syntax::{
+    ast::{AstNode, FnDef, FnDefNode},
+};
+
+use crate::{
+    descriptors::{
+        DescriptorDatabase,
+        function::{FnId, FnScopes},
+    },
+};
+
+/// Resolve `FnId` to the corresponding `SyntaxNode`
+/// TODO: this should return something more type-safe then `SyntaxNode`
+pub(crate) fn fn_syntax(db: &impl DescriptorDatabase, fn_id: FnId) -> FnDefNode {
+    let syntax = db.resolve_syntax_ptr(fn_id.0);
+    let fn_def = FnDef::cast(syntax.borrowed()).unwrap();
+    FnDefNode::new(fn_def)
+}
+
+pub(crate) fn fn_scopes(db: &impl DescriptorDatabase, fn_id: FnId) -> Arc<FnScopes> {
+    let syntax = db.fn_syntax(fn_id);
+    let res = FnScopes::new(syntax.ast());
+    Arc::new(res)
+}
diff --git a/crates/ra_analysis/src/descriptors/function/mod.rs b/crates/ra_analysis/src/descriptors/function/mod.rs
new file mode 100644
index 000000000..687413ddc
--- /dev/null
+++ b/crates/ra_analysis/src/descriptors/function/mod.rs
@@ -0,0 +1,83 @@
+pub(super) mod imp;
+mod scope;
+
+use ra_syntax::{
+    ast::{self, AstNode, NameOwner}
+};
+
+use crate::{
+    FileId,
+    syntax_ptr::SyntaxPtr
+};
+
+pub(crate) use self::scope::FnScopes;
+
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub(crate) struct FnId(SyntaxPtr);
+
+impl FnId {
+    pub(crate) fn new(file_id: FileId, fn_def: ast::FnDef) -> FnId {
+        let ptr = SyntaxPtr::new(file_id, fn_def.syntax());
+        FnId(ptr)
+    }
+}
+
+
+#[derive(Debug, Clone)]
+pub struct FnDescriptor {
+    pub name: String,
+    pub label: String,
+    pub ret_type: Option<String>,
+    pub params: Vec<String>,
+}
+
+impl FnDescriptor {
+    pub fn new(node: ast::FnDef) -> Option<Self> {
+        let name = node.name()?.text().to_string();
+
+        // Strip the body out for the label.
+        let label: String = if let Some(body) = node.body() {
+            let body_range = body.syntax().range();
+            let label: String = node
+                .syntax()
+                .children()
+                .filter(|child| !child.range().is_subrange(&body_range))
+                .map(|node| node.text().to_string())
+                .collect();
+            label
+        } else {
+            node.syntax().text().to_string()
+        };
+
+        let params = FnDescriptor::param_list(node);
+        let ret_type = node.ret_type().map(|r| r.syntax().text().to_string());
+
+        Some(FnDescriptor {
+            name,
+            ret_type,
+            params,
+            label,
+        })
+    }
+
+    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()),
+            );
+        }
+        res
+    }
+}
+
diff --git a/crates/ra_analysis/src/descriptors/function/scope.rs b/crates/ra_analysis/src/descriptors/function/scope.rs
new file mode 100644
index 000000000..5333a0a3b
--- /dev/null
+++ b/crates/ra_analysis/src/descriptors/function/scope.rs
@@ -0,0 +1,435 @@
+use rustc_hash::FxHashMap;
+
+use ra_syntax::{
+    algo::generate,
+    ast::{self, ArgListOwner, LoopBodyOwner, NameOwner},
+    AstNode, SmolStr, SyntaxNodeRef,
+};
+
+use crate::syntax_ptr::LocalSyntaxPtr;
+
+#[derive(Clone, Copy, PartialEq, Eq, Debug)]
+pub(crate) struct ScopeId(u32);
+
+#[derive(Debug, PartialEq, Eq)]
+pub struct FnScopes {
+    pub(crate) self_param: Option<LocalSyntaxPtr>,
+    scopes: Vec<ScopeData>,
+    scope_for: FxHashMap<LocalSyntaxPtr, ScopeId>,
+}
+
+#[derive(Debug, PartialEq, Eq)]
+pub struct ScopeEntry {
+    name: SmolStr,
+    ptr: LocalSyntaxPtr,
+}
+
+#[derive(Debug, PartialEq, Eq)]
+struct ScopeData {
+    parent: Option<ScopeId>,
+    entries: Vec<ScopeEntry>,
+}
+
+impl FnScopes {
+    pub(crate) fn new(fn_def: ast::FnDef) -> FnScopes {
+        let mut scopes = FnScopes {
+            self_param: fn_def
+                .param_list()
+                .and_then(|it| it.self_param())
+                .map(|it| LocalSyntaxPtr::new(it.syntax())),
+            scopes: Vec::new(),
+            scope_for: FxHashMap::default(),
+        };
+        let root = scopes.root_scope();
+        scopes.add_params_bindings(root, fn_def.param_list());
+        if let Some(body) = fn_def.body() {
+            compute_block_scopes(body, &mut scopes, root)
+        }
+        scopes
+    }
+    pub(crate) fn entries(&self, scope: ScopeId) -> &[ScopeEntry] {
+        &self.get(scope).entries
+    }
+    pub fn scope_chain<'a>(&'a self, node: SyntaxNodeRef) -> impl Iterator<Item = ScopeId> + 'a {
+        generate(self.scope_for(node), move |&scope| {
+            self.get(scope).parent
+        })
+    }
+    fn root_scope(&mut self) -> ScopeId {
+        let res = ScopeId(self.scopes.len() as u32);
+        self.scopes.push(ScopeData {
+            parent: None,
+            entries: vec![],
+        });
+        res
+    }
+    fn new_scope(&mut self, parent: ScopeId) -> ScopeId {
+        let res = ScopeId(self.scopes.len() as u32);
+        self.scopes.push(ScopeData {
+            parent: Some(parent),
+            entries: vec![],
+        });
+        res
+    }
+    fn add_bindings(&mut self, scope: ScopeId, pat: ast::Pat) {
+        let entries = pat
+            .syntax()
+            .descendants()
+            .filter_map(ast::BindPat::cast)
+            .filter_map(ScopeEntry::new);
+        self.get_mut(scope).entries.extend(entries);
+    }
+    fn add_params_bindings(&mut self, scope: ScopeId, params: Option<ast::ParamList>) {
+        params
+            .into_iter()
+            .flat_map(|it| it.params())
+            .filter_map(|it| it.pat())
+            .for_each(|it| self.add_bindings(scope, it));
+    }
+    fn set_scope(&mut self, node: SyntaxNodeRef, scope: ScopeId) {
+        self.scope_for.insert(LocalSyntaxPtr::new(node), scope);
+    }
+    fn scope_for(&self, node: SyntaxNodeRef) -> Option<ScopeId> {
+        node.ancestors()
+            .map(LocalSyntaxPtr::new)
+            .filter_map(|it| self.scope_for.get(&it).map(|&scope| scope))
+            .next()
+    }
+    fn get(&self, scope: ScopeId) -> &ScopeData {
+        &self.scopes[scope.0 as usize]
+    }
+    fn get_mut(&mut self, scope: ScopeId) -> &mut ScopeData {
+        &mut self.scopes[scope.0 as usize]
+    }
+}
+
+impl ScopeEntry {
+    fn new(pat: ast::BindPat) -> Option<ScopeEntry> {
+        let name = pat.name()?;
+        let res = ScopeEntry {
+            name: name.text(),
+            ptr: LocalSyntaxPtr::new(pat.syntax()),
+        };
+        Some(res)
+    }
+    pub(crate) fn name(&self) -> &SmolStr {
+        &self.name
+    }
+    pub(crate) fn ptr(&self) -> LocalSyntaxPtr {
+        self.ptr
+    }
+}
+
+fn compute_block_scopes(block: ast::Block, scopes: &mut FnScopes, mut scope: ScopeId) {
+    for stmt in block.statements() {
+        match stmt {
+            ast::Stmt::LetStmt(stmt) => {
+                if let Some(expr) = stmt.initializer() {
+                    scopes.set_scope(expr.syntax(), scope);
+                    compute_expr_scopes(expr, scopes, scope);
+                }
+                scope = scopes.new_scope(scope);
+                if let Some(pat) = stmt.pat() {
+                    scopes.add_bindings(scope, pat);
+                }
+            }
+            ast::Stmt::ExprStmt(expr_stmt) => {
+                if let Some(expr) = expr_stmt.expr() {
+                    scopes.set_scope(expr.syntax(), scope);
+                    compute_expr_scopes(expr, scopes, scope);
+                }
+            }
+        }
+    }
+    if let Some(expr) = block.expr() {
+        scopes.set_scope(expr.syntax(), scope);
+        compute_expr_scopes(expr, scopes, scope);
+    }
+}
+
+fn compute_expr_scopes(expr: ast::Expr, scopes: &mut FnScopes, scope: ScopeId) {
+    match expr {
+        ast::Expr::IfExpr(e) => {
+            let cond_scope = e
+                .condition()
+                .and_then(|cond| compute_cond_scopes(cond, scopes, scope));
+            if let Some(block) = e.then_branch() {
+                compute_block_scopes(block, scopes, cond_scope.unwrap_or(scope));
+            }
+            if let Some(block) = e.else_branch() {
+                compute_block_scopes(block, scopes, scope);
+            }
+        }
+        ast::Expr::BlockExpr(e) => {
+            if let Some(block) = e.block() {
+                compute_block_scopes(block, scopes, scope);
+            }
+        }
+        ast::Expr::LoopExpr(e) => {
+            if let Some(block) = e.loop_body() {
+                compute_block_scopes(block, scopes, scope);
+            }
+        }
+        ast::Expr::WhileExpr(e) => {
+            let cond_scope = e
+                .condition()
+                .and_then(|cond| compute_cond_scopes(cond, scopes, scope));
+            if let Some(block) = e.loop_body() {
+                compute_block_scopes(block, scopes, cond_scope.unwrap_or(scope));
+            }
+        }
+        ast::Expr::ForExpr(e) => {
+            if let Some(expr) = e.iterable() {
+                compute_expr_scopes(expr, scopes, scope);
+            }
+            let mut scope = scope;
+            if let Some(pat) = e.pat() {
+                scope = scopes.new_scope(scope);
+                scopes.add_bindings(scope, pat);
+            }
+            if let Some(block) = e.loop_body() {
+                compute_block_scopes(block, scopes, scope);
+            }
+        }
+        ast::Expr::LambdaExpr(e) => {
+            let scope = scopes.new_scope(scope);
+            scopes.add_params_bindings(scope, e.param_list());
+            if let Some(body) = e.body() {
+                scopes.set_scope(body.syntax(), scope);
+                compute_expr_scopes(body, scopes, scope);
+            }
+        }
+        ast::Expr::CallExpr(e) => {
+            compute_call_scopes(e.expr(), e.arg_list(), scopes, scope);
+        }
+        ast::Expr::MethodCallExpr(e) => {
+            compute_call_scopes(e.expr(), e.arg_list(), scopes, scope);
+        }
+        ast::Expr::MatchExpr(e) => {
+            if let Some(expr) = e.expr() {
+                compute_expr_scopes(expr, scopes, scope);
+            }
+            for arm in e.match_arm_list().into_iter().flat_map(|it| it.arms()) {
+                let scope = scopes.new_scope(scope);
+                for pat in arm.pats() {
+                    scopes.add_bindings(scope, pat);
+                }
+                if let Some(expr) = arm.expr() {
+                    compute_expr_scopes(expr, scopes, scope);
+                }
+            }
+        }
+        _ => expr
+            .syntax()
+            .children()
+            .filter_map(ast::Expr::cast)
+            .for_each(|expr| compute_expr_scopes(expr, scopes, scope)),
+    };
+
+    fn compute_call_scopes(
+        receiver: Option<ast::Expr>,
+        arg_list: Option<ast::ArgList>,
+        scopes: &mut FnScopes,
+        scope: ScopeId,
+    ) {
+        arg_list
+            .into_iter()
+            .flat_map(|it| it.args())
+            .chain(receiver)
+            .for_each(|expr| compute_expr_scopes(expr, scopes, scope));
+    }
+
+    fn compute_cond_scopes(
+        cond: ast::Condition,
+        scopes: &mut FnScopes,
+        scope: ScopeId,
+    ) -> Option<ScopeId> {
+        if let Some(expr) = cond.expr() {
+            compute_expr_scopes(expr, scopes, scope);
+        }
+        if let Some(pat) = cond.pat() {
+            let s = scopes.new_scope(scope);
+            scopes.add_bindings(s, pat);
+            Some(s)
+        } else {
+            None
+        }
+    }
+}
+
+pub fn resolve_local_name<'a>(
+    name_ref: ast::NameRef,
+    scopes: &'a FnScopes,
+) -> Option<&'a ScopeEntry> {
+    use rustc_hash::FxHashSet;
+
+    let mut shadowed = FxHashSet::default();
+    let ret = scopes
+        .scope_chain(name_ref.syntax())
+        .flat_map(|scope| scopes.entries(scope).iter())
+        .filter(|entry| shadowed.insert(entry.name()))
+        .filter(|entry| entry.name() == &name_ref.text())
+        .nth(0);
+    ret
+}
+
+#[cfg(test)]
+mod tests {
+    use ra_syntax::File;
+    use test_utils::extract_offset;
+    use ra_editor::{find_node_at_offset};
+
+    use super::*;
+
+
+    fn do_check(code: &str, expected: &[&str]) {
+        let (off, code) = extract_offset(code);
+        let code = {
+            let mut buf = String::new();
+            let off = u32::from(off) as usize;
+            buf.push_str(&code[..off]);
+            buf.push_str("marker");
+            buf.push_str(&code[off..]);
+            buf
+        };
+        let file = File::parse(&code);
+        let marker: ast::PathExpr = find_node_at_offset(file.syntax(), off).unwrap();
+        let fn_def: ast::FnDef = find_node_at_offset(file.syntax(), off).unwrap();
+        let scopes = FnScopes::new(fn_def);
+        let actual = scopes
+            .scope_chain(marker.syntax())
+            .flat_map(|scope| scopes.entries(scope))
+            .map(|it| it.name())
+            .collect::<Vec<_>>();
+        assert_eq!(actual.as_slice(), expected);
+    }
+
+    #[test]
+    fn test_lambda_scope() {
+        do_check(
+            r"
+            fn quux(foo: i32) {
+                let f = |bar, baz: i32| {
+                    <|>
+                };
+            }",
+            &["bar", "baz", "foo"],
+        );
+    }
+
+    #[test]
+    fn test_call_scope() {
+        do_check(
+            r"
+            fn quux() {
+                f(|x| <|> );
+            }",
+            &["x"],
+        );
+    }
+
+    #[test]
+    fn test_metod_call_scope() {
+        do_check(
+            r"
+            fn quux() {
+                z.f(|x| <|> );
+            }",
+            &["x"],
+        );
+    }
+
+    #[test]
+    fn test_loop_scope() {
+        do_check(
+            r"
+            fn quux() {
+                loop {
+                    let x = ();
+                    <|>
+                };
+            }",
+            &["x"],
+        );
+    }
+
+    #[test]
+    fn test_match() {
+        do_check(
+            r"
+            fn quux() {
+                match () {
+                    Some(x) => {
+                        <|>
+                    }
+                };
+            }",
+            &["x"],
+        );
+    }
+
+    #[test]
+    fn test_shadow_variable() {
+        do_check(
+            r"
+            fn foo(x: String) {
+                let x : &str = &x<|>;
+            }",
+            &["x"],
+        );
+    }
+
+    fn do_check_local_name(code: &str, expected_offset: u32) {
+        let (off, code) = extract_offset(code);
+        let file = File::parse(&code);
+        let fn_def: ast::FnDef = find_node_at_offset(file.syntax(), off).unwrap();
+        let name_ref: ast::NameRef = find_node_at_offset(file.syntax(), off).unwrap();
+
+        let scopes = FnScopes::new(fn_def);
+
+        let local_name_entry = resolve_local_name(name_ref, &scopes).unwrap();
+        let local_name = local_name_entry.ptr().resolve(&file);
+        let expected_name =
+            find_node_at_offset::<ast::Name>(file.syntax(), expected_offset.into()).unwrap();
+        assert_eq!(local_name.range(), expected_name.syntax().range());
+    }
+
+    #[test]
+    fn test_resolve_local_name() {
+        do_check_local_name(
+            r#"
+            fn foo(x: i32, y: u32) {
+                {
+                    let z = x * 2;
+                }
+                {
+                    let t = x<|> * 3;
+                }
+            }"#,
+            21,
+        );
+    }
+
+    #[test]
+    fn test_resolve_local_name_declaration() {
+        do_check_local_name(
+            r#"
+            fn foo(x: String) {
+                let x : &str = &x<|>;
+            }"#,
+            21,
+        );
+    }
+
+    #[test]
+    fn test_resolve_local_name_shadow() {
+        do_check_local_name(
+            r"
+        fn foo(x: String) {
+            let x : &str = &x;
+            x<|>
+        }",
+            46,
+        );
+    }
+}
diff --git a/crates/ra_analysis/src/descriptors/mod.rs b/crates/ra_analysis/src/descriptors/mod.rs
index 0220f7d5d..0c4991757 100644
--- a/crates/ra_analysis/src/descriptors/mod.rs
+++ b/crates/ra_analysis/src/descriptors/mod.rs
@@ -1,62 +1,46 @@
 pub(crate) mod module;
+pub(crate) mod function;
+
+use std::sync::Arc;
 
 use ra_syntax::{
-    ast::{self, AstNode, NameOwner},
+    SmolStr,
+    ast::{FnDefNode},
 };
 
-#[derive(Debug, Clone)]
-pub struct FnDescriptor {
-    pub name: String,
-    pub label: String,
-    pub ret_type: Option<String>,
-    pub params: Vec<String>,
-}
-
-impl FnDescriptor {
-    pub fn new(node: ast::FnDef) -> Option<Self> {
-        let name = node.name()?.text().to_string();
-
-        // Strip the body out for the label.
-        let label: String = if let Some(body) = node.body() {
-            let body_range = body.syntax().range();
-            let label: String = node
-                .syntax()
-                .children()
-                .filter(|child| !child.range().is_subrange(&body_range))
-                .map(|node| node.text().to_string())
-                .collect();
-            label
-        } else {
-            node.syntax().text().to_string()
-        };
-
-        let params = FnDescriptor::param_list(node);
-        let ret_type = node.ret_type().map(|r| r.syntax().text().to_string());
-
-        Some(FnDescriptor {
-            name,
-            ret_type,
-            params,
-            label,
-        })
-    }
+use crate::{
+    FileId, Cancelable,
+    db::SyntaxDatabase,
+    descriptors::module::{ModuleTree, ModuleId, ModuleScope},
+    descriptors::function::{FnId, FnScopes},
+    input::SourceRootId,
+    syntax_ptr::SyntaxPtrDatabase,
+};
 
-    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()),
-            );
+salsa::query_group! {
+    pub(crate) trait DescriptorDatabase: SyntaxDatabase + SyntaxPtrDatabase {
+        fn module_tree(source_root_id: SourceRootId) -> Cancelable<Arc<ModuleTree>> {
+            type ModuleTreeQuery;
+            use fn module::imp::module_tree;
+        }
+        fn submodules(file_id: FileId) -> Cancelable<Arc<Vec<SmolStr>>> {
+            type SubmodulesQuery;
+            use fn module::imp::submodules;
+        }
+        fn module_scope(source_root_id: SourceRootId, module_id: ModuleId) -> Cancelable<Arc<ModuleScope>> {
+            type ModuleScopeQuery;
+            use fn module::imp::module_scope;
+        }
+        fn fn_syntax(fn_id: FnId) -> FnDefNode {
+            type FnSyntaxQuery;
+            // Don't retain syntax trees in memory
+            storage volatile;
+            use fn function::imp::fn_syntax;
+        }
+        fn fn_scopes(fn_id: FnId) -> Arc<FnScopes> {
+            type FnScopesQuery;
+            use fn function::imp::fn_scopes;
         }
-        res
     }
 }
diff --git a/crates/ra_analysis/src/descriptors/module/imp.rs b/crates/ra_analysis/src/descriptors/module/imp.rs
index 5fdaad137..dae3a356d 100644
--- a/crates/ra_analysis/src/descriptors/module/imp.rs
+++ b/crates/ra_analysis/src/descriptors/module/imp.rs
@@ -10,14 +10,15 @@ use ra_syntax::{
 use crate::{
     FileId, Cancelable, FileResolverImp, db,
     input::{SourceRoot, SourceRootId},
+    descriptors::DescriptorDatabase,
 };
 
 use super::{
-    ModuleData, ModuleTree, ModuleId, LinkId, LinkData, Problem, ModulesDatabase, ModuleScope
+    ModuleData, ModuleTree, ModuleId, LinkId, LinkData, Problem, ModuleScope
 };
 
 
-pub(super) fn submodules(db: &impl ModulesDatabase, file_id: FileId) -> Cancelable<Arc<Vec<SmolStr>>> {
+pub(crate) fn submodules(db: &impl DescriptorDatabase, file_id: FileId) -> Cancelable<Arc<Vec<SmolStr>>> {
     db::check_canceled(db)?;
     let file = db.file_syntax(file_id);
     let root = file.ast();
@@ -25,7 +26,7 @@ pub(super) fn submodules(db: &impl ModulesDatabase, file_id: FileId) -> Cancelab
     Ok(Arc::new(submodules))
 }
 
-pub(super) fn modules(root: ast::Root<'_>) -> impl Iterator<Item = (SmolStr, ast::Module<'_>)> {
+pub(crate) fn modules(root: ast::Root<'_>) -> impl Iterator<Item = (SmolStr, ast::Module<'_>)> {
     root.modules().filter_map(|module| {
         let name = module.name()?.text();
         if !module.has_semi() {
@@ -35,8 +36,8 @@ pub(super) fn modules(root: ast::Root<'_>) -> impl Iterator<Item = (SmolStr, ast
     })
 }
 
-pub(super) fn module_scope(
-    db: &impl ModulesDatabase,
+pub(crate) fn module_scope(
+    db: &impl DescriptorDatabase,
     source_root_id: SourceRootId,
     module_id: ModuleId,
 ) -> Cancelable<Arc<ModuleScope>> {
@@ -47,8 +48,8 @@ pub(super) fn module_scope(
     Ok(Arc::new(res))
 }
 
-pub(super) fn module_tree(
-    db: &impl ModulesDatabase,
+pub(crate) fn module_tree(
+    db: &impl DescriptorDatabase,
     source_root: SourceRootId,
 ) -> Cancelable<Arc<ModuleTree>> {
     db::check_canceled(db)?;
@@ -64,7 +65,7 @@ pub struct Submodule {
 
 
 fn create_module_tree<'a>(
-    db: &impl ModulesDatabase,
+    db: &impl DescriptorDatabase,
     source_root: SourceRootId,
 ) -> Cancelable<ModuleTree> {
     let mut tree = ModuleTree {
@@ -88,7 +89,7 @@ fn create_module_tree<'a>(
 }
 
 fn build_subtree(
-    db: &impl ModulesDatabase,
+    db: &impl DescriptorDatabase,
     source_root: &SourceRoot,
     tree: &mut ModuleTree,
     visited: &mut FxHashSet<FileId>,
diff --git a/crates/ra_analysis/src/descriptors/module/mod.rs b/crates/ra_analysis/src/descriptors/module/mod.rs
index 9e5d73f94..667553f74 100644
--- a/crates/ra_analysis/src/descriptors/module/mod.rs
+++ b/crates/ra_analysis/src/descriptors/module/mod.rs
@@ -1,37 +1,13 @@
-mod imp;
+pub(super) mod imp;
 pub(crate) mod scope;
 
-use std::sync::Arc;
-
 use relative_path::RelativePathBuf;
 use ra_syntax::{ast::{self, NameOwner, AstNode}, SmolStr, SyntaxNode};
 
-use crate::{
-    FileId, Cancelable,
-    db::SyntaxDatabase,
-    input::SourceRootId,
-};
+use crate::FileId;
 
 pub(crate) use self::scope::ModuleScope;
 
-salsa::query_group! {
-    pub(crate) trait ModulesDatabase: SyntaxDatabase {
-        fn module_tree(source_root_id: SourceRootId) -> Cancelable<Arc<ModuleTree>> {
-            type ModuleTreeQuery;
-            use fn imp::module_tree;
-        }
-        fn submodules(file_id: FileId) -> Cancelable<Arc<Vec<SmolStr>>> {
-            type SubmodulesQuery;
-            use fn imp::submodules;
-        }
-        fn module_scope(source_root_id: SourceRootId, module_id: ModuleId) -> Cancelable<Arc<ModuleScope>> {
-            type ModuleScopeQuery;
-            use fn imp::module_scope;
-        }
-    }
-}
-
-
 #[derive(Debug, PartialEq, Eq, Hash)]
 pub(crate) struct ModuleTree {
     mods: Vec<ModuleData>,
diff --git a/crates/ra_analysis/src/descriptors/module/scope.rs b/crates/ra_analysis/src/descriptors/module/scope.rs
index da58ddce0..0f8f325ab 100644
--- a/crates/ra_analysis/src/descriptors/module/scope.rs
+++ b/crates/ra_analysis/src/descriptors/module/scope.rs
@@ -2,8 +2,8 @@
 
 
 use ra_syntax::{
-    ast::{self, AstChildren, ModuleItemOwner},
-    File, AstNode, SmolStr, SyntaxNode, SyntaxNodeRef,
+    ast::{self, ModuleItemOwner},
+    File, AstNode, SmolStr,
 };
 
 use crate::syntax_ptr::LocalSyntaxPtr;
@@ -99,7 +99,7 @@ fn collect_imports(tree: ast::UseTree, acc: &mut Vec<Entry>) {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use ra_syntax::{ast::ModuleItemOwner, File};
+    use ra_syntax::{File};
 
     fn do_check(code: &str, expected: &[&str]) {
         let file = File::parse(&code);
diff --git a/crates/ra_analysis/src/imp.rs b/crates/ra_analysis/src/imp.rs
index efb3182a6..49b693ae8 100644
--- a/crates/ra_analysis/src/imp.rs
+++ b/crates/ra_analysis/src/imp.rs
@@ -21,8 +21,9 @@ use crate::{
         self, SyntaxDatabase, FileSyntaxQuery,
     },
     input::{SourceRootId, FilesDatabase, SourceRoot, WORKSPACE},
-    descriptors::module::{ModulesDatabase, ModuleTree, Problem},
-    descriptors::{FnDescriptor},
+    descriptors::DescriptorDatabase,
+    descriptors::module::{ModuleTree, Problem},
+    descriptors::function::{FnDescriptor},
     symbol_index::SymbolIndex,
     CrateGraph, CrateId, Diagnostic, FileId, FileResolver, FileSystemEdit, Position,
     Query, SourceChange, SourceFileEdit, Cancelable,
diff --git a/crates/ra_analysis/src/lib.rs b/crates/ra_analysis/src/lib.rs
index 363c72c0b..a77c9a5fa 100644
--- a/crates/ra_analysis/src/lib.rs
+++ b/crates/ra_analysis/src/lib.rs
@@ -29,7 +29,7 @@ use crate::{
 };
 
 pub use crate::{
-    descriptors::FnDescriptor,
+    descriptors::function::FnDescriptor,
     input::{FileId, FileResolver, CrateGraph, CrateId}
 };
 pub use ra_editor::{
diff --git a/crates/ra_analysis/src/syntax_ptr.rs b/crates/ra_analysis/src/syntax_ptr.rs
index adbff4806..aee214318 100644
--- a/crates/ra_analysis/src/syntax_ptr.rs
+++ b/crates/ra_analysis/src/syntax_ptr.rs
@@ -12,6 +12,7 @@ salsa::query_group! {
     pub(crate) trait SyntaxPtrDatabase: SyntaxDatabase {
         fn resolve_syntax_ptr(ptr: SyntaxPtr) -> SyntaxNode {
             type ResolveSyntaxPtrQuery;
+            // Don't retain syntax trees in memory
             storage volatile;
         }
     }
diff --git a/crates/ra_editor/src/scope/fn_scope.rs b/crates/ra_editor/src/scope/fn_scope.rs
index f10bdf657..f5c113fd9 100644
--- a/crates/ra_editor/src/scope/fn_scope.rs
+++ b/crates/ra_editor/src/scope/fn_scope.rs
@@ -83,6 +83,7 @@ impl FnScopes {
     }
 }
 
+#[derive(PartialEq, Eq)]
 pub struct ScopeEntry {
     syntax: SyntaxNode,
 }
@@ -251,7 +252,7 @@ fn compute_expr_scopes(expr: ast::Expr, scopes: &mut FnScopes, scope: ScopeId) {
     }
 }
 
-#[derive(Debug)]
+#[derive(Debug, PartialEq, Eq)]
 struct ScopeData {
     parent: Option<ScopeId>,
     entries: Vec<ScopeEntry>,
diff --git a/crates/ra_syntax/src/ast/generated.rs b/crates/ra_syntax/src/ast/generated.rs
index 9ba775e1c..d0cd060d3 100644
--- a/crates/ra_syntax/src/ast/generated.rs
+++ b/crates/ra_syntax/src/ast/generated.rs
@@ -15,7 +15,7 @@ use crate::{
 pub struct ArgListNode(SyntaxNode);
 
 impl ArgListNode {
-    pub fn new(&self, ast: ArgList) -> ArgListNode {
+    pub fn new(ast: ArgList) -> ArgListNode {
         let syntax = ast.syntax().owned();
         ArgListNode(syntax)
     }
@@ -50,7 +50,7 @@ impl<'a> ArgList<'a> {
 pub struct ArrayExprNode(SyntaxNode);
 
 impl ArrayExprNode {
-    pub fn new(&self, ast: ArrayExpr) -> ArrayExprNode {
+    pub fn new(ast: ArrayExpr) -> ArrayExprNode {
         let syntax = ast.syntax().owned();
         ArrayExprNode(syntax)
     }
@@ -81,7 +81,7 @@ impl<'a> ArrayExpr<'a> {}
 pub struct ArrayTypeNode(SyntaxNode);
 
 impl ArrayTypeNode {
-    pub fn new(&self, ast: ArrayType) -> ArrayTypeNode {
+    pub fn new(ast: ArrayType) -> ArrayTypeNode {
         let syntax = ast.syntax().owned();
         ArrayTypeNode(syntax)
     }
@@ -112,7 +112,7 @@ impl<'a> ArrayType<'a> {}
 pub struct AttrNode(SyntaxNode);
 
 impl AttrNode {
-    pub fn new(&self, ast: Attr) -> AttrNode {
+    pub fn new(ast: Attr) -> AttrNode {
         let syntax = ast.syntax().owned();
         AttrNode(syntax)
     }
@@ -147,7 +147,7 @@ impl<'a> Attr<'a> {
 pub struct BinExprNode(SyntaxNode);
 
 impl BinExprNode {
-    pub fn new(&self, ast: BinExpr) -> BinExprNode {
+    pub fn new(ast: BinExpr) -> BinExprNode {
         let syntax = ast.syntax().owned();
         BinExprNode(syntax)
     }
@@ -178,7 +178,7 @@ impl<'a> BinExpr<'a> {}
 pub struct BindPatNode(SyntaxNode);
 
 impl BindPatNode {
-    pub fn new(&self, ast: BindPat) -> BindPatNode {
+    pub fn new(ast: BindPat) -> BindPatNode {
         let syntax = ast.syntax().owned();
         BindPatNode(syntax)
     }
@@ -210,7 +210,7 @@ impl<'a> BindPat<'a> {}
 pub struct BlockNode(SyntaxNode);
 
 impl BlockNode {
-    pub fn new(&self, ast: Block) -> BlockNode {
+    pub fn new(ast: Block) -> BlockNode {
         let syntax = ast.syntax().owned();
         BlockNode(syntax)
     }
@@ -249,7 +249,7 @@ impl<'a> Block<'a> {
 pub struct BlockExprNode(SyntaxNode);
 
 impl BlockExprNode {
-    pub fn new(&self, ast: BlockExpr) -> BlockExprNode {
+    pub fn new(ast: BlockExpr) -> BlockExprNode {
         let syntax = ast.syntax().owned();
         BlockExprNode(syntax)
     }
@@ -284,7 +284,7 @@ impl<'a> BlockExpr<'a> {
 pub struct BreakExprNode(SyntaxNode);
 
 impl BreakExprNode {
-    pub fn new(&self, ast: BreakExpr) -> BreakExprNode {
+    pub fn new(ast: BreakExpr) -> BreakExprNode {
         let syntax = ast.syntax().owned();
         BreakExprNode(syntax)
     }
@@ -315,7 +315,7 @@ impl<'a> BreakExpr<'a> {}
 pub struct CallExprNode(SyntaxNode);
 
 impl CallExprNode {
-    pub fn new(&self, ast: CallExpr) -> CallExprNode {
+    pub fn new(ast: CallExpr) -> CallExprNode {
         let syntax = ast.syntax().owned();
         CallExprNode(syntax)
     }
@@ -351,7 +351,7 @@ impl<'a> CallExpr<'a> {
 pub struct CastExprNode(SyntaxNode);
 
 impl CastExprNode {
-    pub fn new(&self, ast: CastExpr) -> CastExprNode {
+    pub fn new(ast: CastExpr) -> CastExprNode {
         let syntax = ast.syntax().owned();
         CastExprNode(syntax)
     }
@@ -382,7 +382,7 @@ impl<'a> CastExpr<'a> {}
 pub struct CommentNode(SyntaxNode);
 
 impl CommentNode {
-    pub fn new(&self, ast: Comment) -> CommentNode {
+    pub fn new(ast: Comment) -> CommentNode {
         let syntax = ast.syntax().owned();
         CommentNode(syntax)
     }
@@ -413,7 +413,7 @@ impl<'a> Comment<'a> {}
 pub struct ConditionNode(SyntaxNode);
 
 impl ConditionNode {
-    pub fn new(&self, ast: Condition) -> ConditionNode {
+    pub fn new(ast: Condition) -> ConditionNode {
         let syntax = ast.syntax().owned();
         ConditionNode(syntax)
     }
@@ -452,7 +452,7 @@ impl<'a> Condition<'a> {
 pub struct ConstDefNode(SyntaxNode);
 
 impl ConstDefNode {
-    pub fn new(&self, ast: ConstDef) -> ConstDefNode {
+    pub fn new(ast: ConstDef) -> ConstDefNode {
         let syntax = ast.syntax().owned();
         ConstDefNode(syntax)
     }
@@ -486,7 +486,7 @@ impl<'a> ConstDef<'a> {}
 pub struct ContinueExprNode(SyntaxNode);
 
 impl ContinueExprNode {
-    pub fn new(&self, ast: ContinueExpr) -> ContinueExprNode {
+    pub fn new(ast: ContinueExpr) -> ContinueExprNode {
         let syntax = ast.syntax().owned();
         ContinueExprNode(syntax)
     }
@@ -517,7 +517,7 @@ impl<'a> ContinueExpr<'a> {}
 pub struct DynTraitTypeNode(SyntaxNode);
 
 impl DynTraitTypeNode {
-    pub fn new(&self, ast: DynTraitType) -> DynTraitTypeNode {
+    pub fn new(ast: DynTraitType) -> DynTraitTypeNode {
         let syntax = ast.syntax().owned();
         DynTraitTypeNode(syntax)
     }
@@ -548,7 +548,7 @@ impl<'a> DynTraitType<'a> {}
 pub struct EnumDefNode(SyntaxNode);
 
 impl EnumDefNode {
-    pub fn new(&self, ast: EnumDef) -> EnumDefNode {
+    pub fn new(ast: EnumDef) -> EnumDefNode {
         let syntax = ast.syntax().owned();
         EnumDefNode(syntax)
     }
@@ -582,7 +582,7 @@ impl<'a> EnumDef<'a> {}
 pub struct ExprNode(SyntaxNode);
 
 impl ExprNode {
-    pub fn new(&self, ast: Expr) -> ExprNode {
+    pub fn new(ast: Expr) -> ExprNode {
         let syntax = ast.syntax().owned();
         ExprNode(syntax)
     }
@@ -710,7 +710,7 @@ impl<'a> Expr<'a> {}
 pub struct ExprStmtNode(SyntaxNode);
 
 impl ExprStmtNode {
-    pub fn new(&self, ast: ExprStmt) -> ExprStmtNode {
+    pub fn new(ast: ExprStmt) -> ExprStmtNode {
         let syntax = ast.syntax().owned();
         ExprStmtNode(syntax)
     }
@@ -745,7 +745,7 @@ impl<'a> ExprStmt<'a> {
 pub struct ExternCrateItemNode(SyntaxNode);
 
 impl ExternCrateItemNode {
-    pub fn new(&self, ast: ExternCrateItem) -> ExternCrateItemNode {
+    pub fn new(ast: ExternCrateItem) -> ExternCrateItemNode {
         let syntax = ast.syntax().owned();
         ExternCrateItemNode(syntax)
     }
@@ -776,7 +776,7 @@ impl<'a> ExternCrateItem<'a> {}
 pub struct FieldExprNode(SyntaxNode);
 
 impl FieldExprNode {
-    pub fn new(&self, ast: FieldExpr) -> FieldExprNode {
+    pub fn new(ast: FieldExpr) -> FieldExprNode {
         let syntax = ast.syntax().owned();
         FieldExprNode(syntax)
     }
@@ -807,7 +807,7 @@ impl<'a> FieldExpr<'a> {}
 pub struct FieldPatListNode(SyntaxNode);
 
 impl FieldPatListNode {
-    pub fn new(&self, ast: FieldPatList) -> FieldPatListNode {
+    pub fn new(ast: FieldPatList) -> FieldPatListNode {
         let syntax = ast.syntax().owned();
         FieldPatListNode(syntax)
     }
@@ -838,7 +838,7 @@ impl<'a> FieldPatList<'a> {}
 pub struct FnDefNode(SyntaxNode);
 
 impl FnDefNode {
-    pub fn new(&self, ast: FnDef) -> FnDefNode {
+    pub fn new(ast: FnDef) -> FnDefNode {
         let syntax = ast.syntax().owned();
         FnDefNode(syntax)
     }
@@ -884,7 +884,7 @@ impl<'a> FnDef<'a> {
 pub struct FnPointerTypeNode(SyntaxNode);
 
 impl FnPointerTypeNode {
-    pub fn new(&self, ast: FnPointerType) -> FnPointerTypeNode {
+    pub fn new(ast: FnPointerType) -> FnPointerTypeNode {
         let syntax = ast.syntax().owned();
         FnPointerTypeNode(syntax)
     }
@@ -915,7 +915,7 @@ impl<'a> FnPointerType<'a> {}
 pub struct ForExprNode(SyntaxNode);
 
 impl ForExprNode {
-    pub fn new(&self, ast: ForExpr) -> ForExprNode {
+    pub fn new(ast: ForExpr) -> ForExprNode {
         let syntax = ast.syntax().owned();
         ForExprNode(syntax)
     }
@@ -955,7 +955,7 @@ impl<'a> ForExpr<'a> {
 pub struct ForTypeNode(SyntaxNode);
 
 impl ForTypeNode {
-    pub fn new(&self, ast: ForType) -> ForTypeNode {
+    pub fn new(ast: ForType) -> ForTypeNode {
         let syntax = ast.syntax().owned();
         ForTypeNode(syntax)
     }
@@ -986,7 +986,7 @@ impl<'a> ForType<'a> {}
 pub struct IfExprNode(SyntaxNode);
 
 impl IfExprNode {
-    pub fn new(&self, ast: IfExpr) -> IfExprNode {
+    pub fn new(ast: IfExpr) -> IfExprNode {
         let syntax = ast.syntax().owned();
         IfExprNode(syntax)
     }
@@ -1021,7 +1021,7 @@ impl<'a> IfExpr<'a> {
 pub struct ImplItemNode(SyntaxNode);
 
 impl ImplItemNode {
-    pub fn new(&self, ast: ImplItem) -> ImplItemNode {
+    pub fn new(ast: ImplItem) -> ImplItemNode {
         let syntax = ast.syntax().owned();
         ImplItemNode(syntax)
     }
@@ -1052,7 +1052,7 @@ impl<'a> ImplItem<'a> {}
 pub struct ImplTraitTypeNode(SyntaxNode);
 
 impl ImplTraitTypeNode {
-    pub fn new(&self, ast: ImplTraitType) -> ImplTraitTypeNode {
+    pub fn new(ast: ImplTraitType) -> ImplTraitTypeNode {
         let syntax = ast.syntax().owned();
         ImplTraitTypeNode(syntax)
     }
@@ -1083,7 +1083,7 @@ impl<'a> ImplTraitType<'a> {}
 pub struct IndexExprNode(SyntaxNode);
 
 impl IndexExprNode {
-    pub fn new(&self, ast: IndexExpr) -> IndexExprNode {
+    pub fn new(ast: IndexExpr) -> IndexExprNode {
         let syntax = ast.syntax().owned();
         IndexExprNode(syntax)
     }
@@ -1114,7 +1114,7 @@ impl<'a> IndexExpr<'a> {}
 pub struct ItemListNode(SyntaxNode);
 
 impl ItemListNode {
-    pub fn new(&self, ast: ItemList) -> ItemListNode {
+    pub fn new(ast: ItemList) -> ItemListNode {
         let syntax = ast.syntax().owned();
         ItemListNode(syntax)
     }
@@ -1147,7 +1147,7 @@ impl<'a> ItemList<'a> {}
 pub struct LabelNode(SyntaxNode);
 
 impl LabelNode {
-    pub fn new(&self, ast: Label) -> LabelNode {
+    pub fn new(ast: Label) -> LabelNode {
         let syntax = ast.syntax().owned();
         LabelNode(syntax)
     }
@@ -1178,7 +1178,7 @@ impl<'a> Label<'a> {}
 pub struct LambdaExprNode(SyntaxNode);
 
 impl LambdaExprNode {
-    pub fn new(&self, ast: LambdaExpr) -> LambdaExprNode {
+    pub fn new(ast: LambdaExpr) -> LambdaExprNode {
         let syntax = ast.syntax().owned();
         LambdaExprNode(syntax)
     }
@@ -1217,7 +1217,7 @@ impl<'a> LambdaExpr<'a> {
 pub struct LetStmtNode(SyntaxNode);
 
 impl LetStmtNode {
-    pub fn new(&self, ast: LetStmt) -> LetStmtNode {
+    pub fn new(ast: LetStmt) -> LetStmtNode {
         let syntax = ast.syntax().owned();
         LetStmtNode(syntax)
     }
@@ -1256,7 +1256,7 @@ impl<'a> LetStmt<'a> {
 pub struct LifetimeNode(SyntaxNode);
 
 impl LifetimeNode {
-    pub fn new(&self, ast: Lifetime) -> LifetimeNode {
+    pub fn new(ast: Lifetime) -> LifetimeNode {
         let syntax = ast.syntax().owned();
         LifetimeNode(syntax)
     }
@@ -1287,7 +1287,7 @@ impl<'a> Lifetime<'a> {}
 pub struct LifetimeParamNode(SyntaxNode);
 
 impl LifetimeParamNode {
-    pub fn new(&self, ast: LifetimeParam) -> LifetimeParamNode {
+    pub fn new(ast: LifetimeParam) -> LifetimeParamNode {
         let syntax = ast.syntax().owned();
         LifetimeParamNode(syntax)
     }
@@ -1322,7 +1322,7 @@ impl<'a> LifetimeParam<'a> {
 pub struct LiteralNode(SyntaxNode);
 
 impl LiteralNode {
-    pub fn new(&self, ast: Literal) -> LiteralNode {
+    pub fn new(ast: Literal) -> LiteralNode {
         let syntax = ast.syntax().owned();
         LiteralNode(syntax)
     }
@@ -1353,7 +1353,7 @@ impl<'a> Literal<'a> {}
 pub struct LoopExprNode(SyntaxNode);
 
 impl LoopExprNode {
-    pub fn new(&self, ast: LoopExpr) -> LoopExprNode {
+    pub fn new(ast: LoopExpr) -> LoopExprNode {
         let syntax = ast.syntax().owned();
         LoopExprNode(syntax)
     }
@@ -1385,7 +1385,7 @@ impl<'a> LoopExpr<'a> {}
 pub struct MatchArmNode(SyntaxNode);
 
 impl MatchArmNode {
-    pub fn new(&self, ast: MatchArm) -> MatchArmNode {
+    pub fn new(ast: MatchArm) -> MatchArmNode {
         let syntax = ast.syntax().owned();
         MatchArmNode(syntax)
     }
@@ -1428,7 +1428,7 @@ impl<'a> MatchArm<'a> {
 pub struct MatchArmListNode(SyntaxNode);
 
 impl MatchArmListNode {
-    pub fn new(&self, ast: MatchArmList) -> MatchArmListNode {
+    pub fn new(ast: MatchArmList) -> MatchArmListNode {
         let syntax = ast.syntax().owned();
         MatchArmListNode(syntax)
     }
@@ -1463,7 +1463,7 @@ impl<'a> MatchArmList<'a> {
 pub struct MatchExprNode(SyntaxNode);
 
 impl MatchExprNode {
-    pub fn new(&self, ast: MatchExpr) -> MatchExprNode {
+    pub fn new(ast: MatchExpr) -> MatchExprNode {
         let syntax = ast.syntax().owned();
         MatchExprNode(syntax)
     }
@@ -1502,7 +1502,7 @@ impl<'a> MatchExpr<'a> {
 pub struct MatchGuardNode(SyntaxNode);
 
 impl MatchGuardNode {
-    pub fn new(&self, ast: MatchGuard) -> MatchGuardNode {
+    pub fn new(ast: MatchGuard) -> MatchGuardNode {
         let syntax = ast.syntax().owned();
         MatchGuardNode(syntax)
     }
@@ -1533,7 +1533,7 @@ impl<'a> MatchGuard<'a> {}
 pub struct MethodCallExprNode(SyntaxNode);
 
 impl MethodCallExprNode {
-    pub fn new(&self, ast: MethodCallExpr) -> MethodCallExprNode {
+    pub fn new(ast: MethodCallExpr) -> MethodCallExprNode {
         let syntax = ast.syntax().owned();
         MethodCallExprNode(syntax)
     }
@@ -1569,7 +1569,7 @@ impl<'a> MethodCallExpr<'a> {
 pub struct ModuleNode(SyntaxNode);
 
 impl ModuleNode {
-    pub fn new(&self, ast: Module) -> ModuleNode {
+    pub fn new(ast: Module) -> ModuleNode {
         let syntax = ast.syntax().owned();
         ModuleNode(syntax)
     }
@@ -1606,7 +1606,7 @@ impl<'a> Module<'a> {
 pub struct ModuleItemNode(SyntaxNode);
 
 impl ModuleItemNode {
-    pub fn new(&self, ast: ModuleItem) -> ModuleItemNode {
+    pub fn new(ast: ModuleItem) -> ModuleItemNode {
         let syntax = ast.syntax().owned();
         ModuleItemNode(syntax)
     }
@@ -1671,7 +1671,7 @@ impl<'a> ModuleItem<'a> {}
 pub struct NameNode(SyntaxNode);
 
 impl NameNode {
-    pub fn new(&self, ast: Name) -> NameNode {
+    pub fn new(ast: Name) -> NameNode {
         let syntax = ast.syntax().owned();
         NameNode(syntax)
     }
@@ -1702,7 +1702,7 @@ impl<'a> Name<'a> {}
 pub struct NameRefNode(SyntaxNode);
 
 impl NameRefNode {
-    pub fn new(&self, ast: NameRef) -> NameRefNode {
+    pub fn new(ast: NameRef) -> NameRefNode {
         let syntax = ast.syntax().owned();
         NameRefNode(syntax)
     }
@@ -1733,7 +1733,7 @@ impl<'a> NameRef<'a> {}
 pub struct NamedFieldNode(SyntaxNode);
 
 impl NamedFieldNode {
-    pub fn new(&self, ast: NamedField) -> NamedFieldNode {
+    pub fn new(ast: NamedField) -> NamedFieldNode {
         let syntax = ast.syntax().owned();
         NamedFieldNode(syntax)
     }
@@ -1764,7 +1764,7 @@ impl<'a> NamedField<'a> {}
 pub struct NamedFieldDefNode(SyntaxNode);
 
 impl NamedFieldDefNode {
-    pub fn new(&self, ast: NamedFieldDef) -> NamedFieldDefNode {
+    pub fn new(ast: NamedFieldDef) -> NamedFieldDefNode {
         let syntax = ast.syntax().owned();
         NamedFieldDefNode(syntax)
     }
@@ -1797,7 +1797,7 @@ impl<'a> NamedFieldDef<'a> {}
 pub struct NamedFieldListNode(SyntaxNode);
 
 impl NamedFieldListNode {
-    pub fn new(&self, ast: NamedFieldList) -> NamedFieldListNode {
+    pub fn new(ast: NamedFieldList) -> NamedFieldListNode {
         let syntax = ast.syntax().owned();
         NamedFieldListNode(syntax)
     }
@@ -1828,7 +1828,7 @@ impl<'a> NamedFieldList<'a> {}
 pub struct NeverTypeNode(SyntaxNode);
 
 impl NeverTypeNode {
-    pub fn new(&self, ast: NeverType) -> NeverTypeNode {
+    pub fn new(ast: NeverType) -> NeverTypeNode {
         let syntax = ast.syntax().owned();
         NeverTypeNode(syntax)
     }
@@ -1859,7 +1859,7 @@ impl<'a> NeverType<'a> {}
 pub struct NominalDefNode(SyntaxNode);
 
 impl NominalDefNode {
-    pub fn new(&self, ast: NominalDef) -> NominalDefNode {
+    pub fn new(ast: NominalDef) -> NominalDefNode {
         let syntax = ast.syntax().owned();
         NominalDefNode(syntax)
     }
@@ -1900,7 +1900,7 @@ impl<'a> NominalDef<'a> {}
 pub struct ParamNode(SyntaxNode);
 
 impl ParamNode {
-    pub fn new(&self, ast: Param) -> ParamNode {
+    pub fn new(ast: Param) -> ParamNode {
         let syntax = ast.syntax().owned();
         ParamNode(syntax)
     }
@@ -1935,7 +1935,7 @@ impl<'a> Param<'a> {
 pub struct ParamListNode(SyntaxNode);
 
 impl ParamListNode {
-    pub fn new(&self, ast: ParamList) -> ParamListNode {
+    pub fn new(ast: ParamList) -> ParamListNode {
         let syntax = ast.syntax().owned();
         ParamListNode(syntax)
     }
@@ -1974,7 +1974,7 @@ impl<'a> ParamList<'a> {
 pub struct ParenExprNode(SyntaxNode);
 
 impl ParenExprNode {
-    pub fn new(&self, ast: ParenExpr) -> ParenExprNode {
+    pub fn new(ast: ParenExpr) -> ParenExprNode {
         let syntax = ast.syntax().owned();
         ParenExprNode(syntax)
     }
@@ -2005,7 +2005,7 @@ impl<'a> ParenExpr<'a> {}
 pub struct ParenTypeNode(SyntaxNode);
 
 impl ParenTypeNode {
-    pub fn new(&self, ast: ParenType) -> ParenTypeNode {
+    pub fn new(ast: ParenType) -> ParenTypeNode {
         let syntax = ast.syntax().owned();
         ParenTypeNode(syntax)
     }
@@ -2036,7 +2036,7 @@ impl<'a> ParenType<'a> {}
 pub struct PatNode(SyntaxNode);
 
 impl PatNode {
-    pub fn new(&self, ast: Pat) -> PatNode {
+    pub fn new(ast: Pat) -> PatNode {
         let syntax = ast.syntax().owned();
         PatNode(syntax)
     }
@@ -2098,7 +2098,7 @@ impl<'a> Pat<'a> {}
 pub struct PathNode(SyntaxNode);
 
 impl PathNode {
-    pub fn new(&self, ast: Path) -> PathNode {
+    pub fn new(ast: Path) -> PathNode {
         let syntax = ast.syntax().owned();
         PathNode(syntax)
     }
@@ -2137,7 +2137,7 @@ impl<'a> Path<'a> {
 pub struct PathExprNode(SyntaxNode);
 
 impl PathExprNode {
-    pub fn new(&self, ast: PathExpr) -> PathExprNode {
+    pub fn new(ast: PathExpr) -> PathExprNode {
         let syntax = ast.syntax().owned();
         PathExprNode(syntax)
     }
@@ -2172,7 +2172,7 @@ impl<'a> PathExpr<'a> {
 pub struct PathPatNode(SyntaxNode);
 
 impl PathPatNode {
-    pub fn new(&self, ast: PathPat) -> PathPatNode {
+    pub fn new(ast: PathPat) -> PathPatNode {
         let syntax = ast.syntax().owned();
         PathPatNode(syntax)
     }
@@ -2203,7 +2203,7 @@ impl<'a> PathPat<'a> {}
 pub struct PathSegmentNode(SyntaxNode);
 
 impl PathSegmentNode {
-    pub fn new(&self, ast: PathSegment) -> PathSegmentNode {
+    pub fn new(ast: PathSegment) -> PathSegmentNode {
         let syntax = ast.syntax().owned();
         PathSegmentNode(syntax)
     }
@@ -2238,7 +2238,7 @@ impl<'a> PathSegment<'a> {
 pub struct PathTypeNode(SyntaxNode);
 
 impl PathTypeNode {
-    pub fn new(&self, ast: PathType) -> PathTypeNode {
+    pub fn new(ast: PathType) -> PathTypeNode {
         let syntax = ast.syntax().owned();
         PathTypeNode(syntax)
     }
@@ -2269,7 +2269,7 @@ impl<'a> PathType<'a> {}
 pub struct PlaceholderPatNode(SyntaxNode);
 
 impl PlaceholderPatNode {
-    pub fn new(&self, ast: PlaceholderPat) -> PlaceholderPatNode {
+    pub fn new(ast: PlaceholderPat) -> PlaceholderPatNode {
         let syntax = ast.syntax().owned();
         PlaceholderPatNode(syntax)
     }
@@ -2300,7 +2300,7 @@ impl<'a> PlaceholderPat<'a> {}
 pub struct PlaceholderTypeNode(SyntaxNode);
 
 impl PlaceholderTypeNode {
-    pub fn new(&self, ast: PlaceholderType) -> PlaceholderTypeNode {
+    pub fn new(ast: PlaceholderType) -> PlaceholderTypeNode {
         let syntax = ast.syntax().owned();
         PlaceholderTypeNode(syntax)
     }
@@ -2331,7 +2331,7 @@ impl<'a> PlaceholderType<'a> {}
 pub struct PointerTypeNode(SyntaxNode);
 
 impl PointerTypeNode {
-    pub fn new(&self, ast: PointerType) -> PointerTypeNode {
+    pub fn new(ast: PointerType) -> PointerTypeNode {
         let syntax = ast.syntax().owned();
         PointerTypeNode(syntax)
     }
@@ -2362,7 +2362,7 @@ impl<'a> PointerType<'a> {}
 pub struct PrefixExprNode(SyntaxNode);
 
 impl PrefixExprNode {
-    pub fn new(&self, ast: PrefixExpr) -> PrefixExprNode {
+    pub fn new(ast: PrefixExpr) -> PrefixExprNode {
         let syntax = ast.syntax().owned();
         PrefixExprNode(syntax)
     }
@@ -2393,7 +2393,7 @@ impl<'a> PrefixExpr<'a> {}
 pub struct RangeExprNode(SyntaxNode);
 
 impl RangeExprNode {
-    pub fn new(&self, ast: RangeExpr) -> RangeExprNode {
+    pub fn new(ast: RangeExpr) -> RangeExprNode {
         let syntax = ast.syntax().owned();
         RangeExprNode(syntax)
     }
@@ -2424,7 +2424,7 @@ impl<'a> RangeExpr<'a> {}
 pub struct RangePatNode(SyntaxNode);
 
 impl RangePatNode {
-    pub fn new(&self, ast: RangePat) -> RangePatNode {
+    pub fn new(ast: RangePat) -> RangePatNode {
         let syntax = ast.syntax().owned();
         RangePatNode(syntax)
     }
@@ -2455,7 +2455,7 @@ impl<'a> RangePat<'a> {}
 pub struct RefExprNode(SyntaxNode);
 
 impl RefExprNode {
-    pub fn new(&self, ast: RefExpr) -> RefExprNode {
+    pub fn new(ast: RefExpr) -> RefExprNode {
         let syntax = ast.syntax().owned();
         RefExprNode(syntax)
     }
@@ -2486,7 +2486,7 @@ impl<'a> RefExpr<'a> {}
 pub struct RefPatNode(SyntaxNode);
 
 impl RefPatNode {
-    pub fn new(&self, ast: RefPat) -> RefPatNode {
+    pub fn new(ast: RefPat) -> RefPatNode {
         let syntax = ast.syntax().owned();
         RefPatNode(syntax)
     }
@@ -2517,7 +2517,7 @@ impl<'a> RefPat<'a> {}
 pub struct ReferenceTypeNode(SyntaxNode);
 
 impl ReferenceTypeNode {
-    pub fn new(&self, ast: ReferenceType) -> ReferenceTypeNode {
+    pub fn new(ast: ReferenceType) -> ReferenceTypeNode {
         let syntax = ast.syntax().owned();
         ReferenceTypeNode(syntax)
     }
@@ -2548,7 +2548,7 @@ impl<'a> ReferenceType<'a> {}
 pub struct RetTypeNode(SyntaxNode);
 
 impl RetTypeNode {
-    pub fn new(&self, ast: RetType) -> RetTypeNode {
+    pub fn new(ast: RetType) -> RetTypeNode {
         let syntax = ast.syntax().owned();
         RetTypeNode(syntax)
     }
@@ -2579,7 +2579,7 @@ impl<'a> RetType<'a> {}
 pub struct ReturnExprNode(SyntaxNode);
 
 impl ReturnExprNode {
-    pub fn new(&self, ast: ReturnExpr) -> ReturnExprNode {
+    pub fn new(ast: ReturnExpr) -> ReturnExprNode {
         let syntax = ast.syntax().owned();
         ReturnExprNode(syntax)
     }
@@ -2610,7 +2610,7 @@ impl<'a> ReturnExpr<'a> {}
 pub struct RootNode(SyntaxNode);
 
 impl RootNode {
-    pub fn new(&self, ast: Root) -> RootNode {
+    pub fn new(ast: Root) -> RootNode {
         let syntax = ast.syntax().owned();
         RootNode(syntax)
     }
@@ -2647,7 +2647,7 @@ impl<'a> Root<'a> {
 pub struct SelfParamNode(SyntaxNode);
 
 impl SelfParamNode {
-    pub fn new(&self, ast: SelfParam) -> SelfParamNode {
+    pub fn new(ast: SelfParam) -> SelfParamNode {
         let syntax = ast.syntax().owned();
         SelfParamNode(syntax)
     }
@@ -2678,7 +2678,7 @@ impl<'a> SelfParam<'a> {}
 pub struct SlicePatNode(SyntaxNode);
 
 impl SlicePatNode {
-    pub fn new(&self, ast: SlicePat) -> SlicePatNode {
+    pub fn new(ast: SlicePat) -> SlicePatNode {
         let syntax = ast.syntax().owned();
         SlicePatNode(syntax)
     }
@@ -2709,7 +2709,7 @@ impl<'a> SlicePat<'a> {}
 pub struct SliceTypeNode(SyntaxNode);
 
 impl SliceTypeNode {
-    pub fn new(&self, ast: SliceType) -> SliceTypeNode {
+    pub fn new(ast: SliceType) -> SliceTypeNode {
         let syntax = ast.syntax().owned();
         SliceTypeNode(syntax)
     }
@@ -2740,7 +2740,7 @@ impl<'a> SliceType<'a> {}
 pub struct StaticDefNode(SyntaxNode);
 
 impl StaticDefNode {
-    pub fn new(&self, ast: StaticDef) -> StaticDefNode {
+    pub fn new(ast: StaticDef) -> StaticDefNode {
         let syntax = ast.syntax().owned();
         StaticDefNode(syntax)
     }
@@ -2774,7 +2774,7 @@ impl<'a> StaticDef<'a> {}
 pub struct StmtNode(SyntaxNode);
 
 impl StmtNode {
-    pub fn new(&self, ast: Stmt) -> StmtNode {
+    pub fn new(ast: Stmt) -> StmtNode {
         let syntax = ast.syntax().owned();
         StmtNode(syntax)
     }
@@ -2812,7 +2812,7 @@ impl<'a> Stmt<'a> {}
 pub struct StructDefNode(SyntaxNode);
 
 impl StructDefNode {
-    pub fn new(&self, ast: StructDef) -> StructDefNode {
+    pub fn new(ast: StructDef) -> StructDefNode {
         let syntax = ast.syntax().owned();
         StructDefNode(syntax)
     }
@@ -2850,7 +2850,7 @@ impl<'a> StructDef<'a> {
 pub struct StructLitNode(SyntaxNode);
 
 impl StructLitNode {
-    pub fn new(&self, ast: StructLit) -> StructLitNode {
+    pub fn new(ast: StructLit) -> StructLitNode {
         let syntax = ast.syntax().owned();
         StructLitNode(syntax)
     }
@@ -2881,7 +2881,7 @@ impl<'a> StructLit<'a> {}
 pub struct StructPatNode(SyntaxNode);
 
 impl StructPatNode {
-    pub fn new(&self, ast: StructPat) -> StructPatNode {
+    pub fn new(ast: StructPat) -> StructPatNode {
         let syntax = ast.syntax().owned();
         StructPatNode(syntax)
     }
@@ -2912,7 +2912,7 @@ impl<'a> StructPat<'a> {}
 pub struct TokenTreeNode(SyntaxNode);
 
 impl TokenTreeNode {
-    pub fn new(&self, ast: TokenTree) -> TokenTreeNode {
+    pub fn new(ast: TokenTree) -> TokenTreeNode {
         let syntax = ast.syntax().owned();
         TokenTreeNode(syntax)
     }
@@ -2943,7 +2943,7 @@ impl<'a> TokenTree<'a> {}
 pub struct TraitDefNode(SyntaxNode);
 
 impl TraitDefNode {
-    pub fn new(&self, ast: TraitDef) -> TraitDefNode {
+    pub fn new(ast: TraitDef) -> TraitDefNode {
         let syntax = ast.syntax().owned();
         TraitDefNode(syntax)
     }
@@ -2976,7 +2976,7 @@ impl<'a> TraitDef<'a> {}
 pub struct TryExprNode(SyntaxNode);
 
 impl TryExprNode {
-    pub fn new(&self, ast: TryExpr) -> TryExprNode {
+    pub fn new(ast: TryExpr) -> TryExprNode {
         let syntax = ast.syntax().owned();
         TryExprNode(syntax)
     }
@@ -3007,7 +3007,7 @@ impl<'a> TryExpr<'a> {}
 pub struct TupleExprNode(SyntaxNode);
 
 impl TupleExprNode {
-    pub fn new(&self, ast: TupleExpr) -> TupleExprNode {
+    pub fn new(ast: TupleExpr) -> TupleExprNode {
         let syntax = ast.syntax().owned();
         TupleExprNode(syntax)
     }
@@ -3038,7 +3038,7 @@ impl<'a> TupleExpr<'a> {}
 pub struct TuplePatNode(SyntaxNode);
 
 impl TuplePatNode {
-    pub fn new(&self, ast: TuplePat) -> TuplePatNode {
+    pub fn new(ast: TuplePat) -> TuplePatNode {
         let syntax = ast.syntax().owned();
         TuplePatNode(syntax)
     }
@@ -3069,7 +3069,7 @@ impl<'a> TuplePat<'a> {}
 pub struct TupleStructPatNode(SyntaxNode);
 
 impl TupleStructPatNode {
-    pub fn new(&self, ast: TupleStructPat) -> TupleStructPatNode {
+    pub fn new(ast: TupleStructPat) -> TupleStructPatNode {
         let syntax = ast.syntax().owned();
         TupleStructPatNode(syntax)
     }
@@ -3100,7 +3100,7 @@ impl<'a> TupleStructPat<'a> {}
 pub struct TupleTypeNode(SyntaxNode);
 
 impl TupleTypeNode {
-    pub fn new(&self, ast: TupleType) -> TupleTypeNode {
+    pub fn new(ast: TupleType) -> TupleTypeNode {
         let syntax = ast.syntax().owned();
         TupleTypeNode(syntax)
     }
@@ -3131,7 +3131,7 @@ impl<'a> TupleType<'a> {}
 pub struct TypeDefNode(SyntaxNode);
 
 impl TypeDefNode {
-    pub fn new(&self, ast: TypeDef) -> TypeDefNode {
+    pub fn new(ast: TypeDef) -> TypeDefNode {
         let syntax = ast.syntax().owned();
         TypeDefNode(syntax)
     }
@@ -3165,7 +3165,7 @@ impl<'a> TypeDef<'a> {}
 pub struct TypeParamNode(SyntaxNode);
 
 impl TypeParamNode {
-    pub fn new(&self, ast: TypeParam) -> TypeParamNode {
+    pub fn new(ast: TypeParam) -> TypeParamNode {
         let syntax = ast.syntax().owned();
         TypeParamNode(syntax)
     }
@@ -3197,7 +3197,7 @@ impl<'a> TypeParam<'a> {}
 pub struct TypeParamListNode(SyntaxNode);
 
 impl TypeParamListNode {
-    pub fn new(&self, ast: TypeParamList) -> TypeParamListNode {
+    pub fn new(ast: TypeParamList) -> TypeParamListNode {
         let syntax = ast.syntax().owned();
         TypeParamListNode(syntax)
     }
@@ -3236,7 +3236,7 @@ impl<'a> TypeParamList<'a> {
 pub struct TypeRefNode(SyntaxNode);
 
 impl TypeRefNode {
-    pub fn new(&self, ast: TypeRef) -> TypeRefNode {
+    pub fn new(ast: TypeRef) -> TypeRefNode {
         let syntax = ast.syntax().owned();
         TypeRefNode(syntax)
     }
@@ -3307,7 +3307,7 @@ impl<'a> TypeRef<'a> {}
 pub struct UseItemNode(SyntaxNode);
 
 impl UseItemNode {
-    pub fn new(&self, ast: UseItem) -> UseItemNode {
+    pub fn new(ast: UseItem) -> UseItemNode {
         let syntax = ast.syntax().owned();
         UseItemNode(syntax)
     }
@@ -3342,7 +3342,7 @@ impl<'a> UseItem<'a> {
 pub struct UseTreeNode(SyntaxNode);
 
 impl UseTreeNode {
-    pub fn new(&self, ast: UseTree) -> UseTreeNode {
+    pub fn new(ast: UseTree) -> UseTreeNode {
         let syntax = ast.syntax().owned();
         UseTreeNode(syntax)
     }
@@ -3381,7 +3381,7 @@ impl<'a> UseTree<'a> {
 pub struct UseTreeListNode(SyntaxNode);
 
 impl UseTreeListNode {
-    pub fn new(&self, ast: UseTreeList) -> UseTreeListNode {
+    pub fn new(ast: UseTreeList) -> UseTreeListNode {
         let syntax = ast.syntax().owned();
         UseTreeListNode(syntax)
     }
@@ -3416,7 +3416,7 @@ impl<'a> UseTreeList<'a> {
 pub struct WhereClauseNode(SyntaxNode);
 
 impl WhereClauseNode {
-    pub fn new(&self, ast: WhereClause) -> WhereClauseNode {
+    pub fn new(ast: WhereClause) -> WhereClauseNode {
         let syntax = ast.syntax().owned();
         WhereClauseNode(syntax)
     }
@@ -3447,7 +3447,7 @@ impl<'a> WhereClause<'a> {}
 pub struct WhileExprNode(SyntaxNode);
 
 impl WhileExprNode {
-    pub fn new(&self, ast: WhileExpr) -> WhileExprNode {
+    pub fn new(ast: WhileExpr) -> WhileExprNode {
         let syntax = ast.syntax().owned();
         WhileExprNode(syntax)
     }
@@ -3483,7 +3483,7 @@ impl<'a> WhileExpr<'a> {
 pub struct WhitespaceNode(SyntaxNode);
 
 impl WhitespaceNode {
-    pub fn new(&self, ast: Whitespace) -> WhitespaceNode {
+    pub fn new(ast: Whitespace) -> WhitespaceNode {
         let syntax = ast.syntax().owned();
         WhitespaceNode(syntax)
     }
diff --git a/crates/ra_syntax/src/ast/generated.rs.tera b/crates/ra_syntax/src/ast/generated.rs.tera
index c61c3e80b..d30038cba 100644
--- a/crates/ra_syntax/src/ast/generated.rs.tera
+++ b/crates/ra_syntax/src/ast/generated.rs.tera
@@ -17,7 +17,7 @@ use crate::{
 pub struct {{ node }}Node(SyntaxNode);
 
 impl {{ node }}Node {
-    pub fn new(&self, ast: {{ node }}) -> {{ node }}Node {
+    pub fn new(ast: {{ node }}) -> {{ node }}Node {
         let syntax = ast.syntax().owned();
         {{ node }}Node(syntax)
     }