Use cached module scopes for completion

5 files changed, 71 insertions, 51 deletions

diff --git a/crates/ra_analysis/src/completion/mod.rs b/crates/ra_analysis/src/completion/mod.rs
index 763533012..2e082705e 100644
--- a/crates/ra_analysis/src/completion/mod.rs
+++ b/crates/ra_analysis/src/completion/mod.rs
@@ -2,6 +2,7 @@ mod reference_completion;
 
 use ra_editor::find_node_at_offset;
 use ra_syntax::{
+    algo::find_leaf_at_offset,
     algo::visit::{visitor_ctx, VisitorCtx},
     ast,
     AstNode, AtomEdit,
@@ -11,6 +12,8 @@ use rustc_hash::{FxHashMap};
 
 use crate::{
     db::{self, SyntaxDatabase},
+    descriptors::{DescriptorDatabase, module::ModuleSource},
+    input::{FilesDatabase},
     Cancelable, FilePosition
 };
 
@@ -35,12 +38,32 @@ pub(crate) fn completions(
         original_file.reparse(&edit)
     };
 
+    let leaf = match find_leaf_at_offset(original_file.syntax(), position.offset).left_biased() {
+        None => return Ok(None),
+        Some(it) => it,
+    };
+    let source_root_id = db.file_source_root(position.file_id);
+    let module_tree = db.module_tree(source_root_id)?;
+    let module_source = ModuleSource::for_node(position.file_id, leaf);
+    let module_id = match module_tree.any_module_for_source(module_source) {
+        None => return Ok(None),
+        Some(it) => it,
+    };
+
     let mut res = Vec::new();
     let mut has_completions = false;
     // First, let's try to complete a reference to some declaration.
     if let Some(name_ref) = find_node_at_offset::<ast::NameRef>(file.syntax(), position.offset) {
         has_completions = true;
-        reference_completion::completions(&mut res, db, position.file_id, &file, name_ref)?;
+        reference_completion::completions(
+            &mut res,
+            db,
+            source_root_id,
+            &module_tree,
+            module_id,
+            &file,
+            name_ref,
+        )?;
         // special case, `trait T { fn foo(i_am_a_name_ref) {} }`
         if is_node::<ast::Param>(name_ref.syntax()) {
             param_completions(name_ref.syntax(), &mut res);
diff --git a/crates/ra_analysis/src/completion/reference_completion.rs b/crates/ra_analysis/src/completion/reference_completion.rs
index b08174968..13d4de9d5 100644
--- a/crates/ra_analysis/src/completion/reference_completion.rs
+++ b/crates/ra_analysis/src/completion/reference_completion.rs
@@ -3,24 +3,26 @@ use ra_editor::find_node_at_offset;
 use ra_syntax::{
     algo::visit::{visitor, Visitor},
     SourceFileNode, AstNode,
-    ast::{self, AstChildren, ModuleItemOwner, LoopBodyOwner},
+    ast::{self, LoopBodyOwner},
     SyntaxKind::*,
 };
 
 use crate::{
     db::RootDatabase,
-    input::FilesDatabase,
+    input::{SourceRootId},
     completion::CompletionItem,
-    descriptors::module::{ModuleId, ModuleScope, ModuleTree, ModuleSource},
+    descriptors::module::{ModuleId, ModuleScope, ModuleTree},
     descriptors::function::FnScopes,
     descriptors::DescriptorDatabase,
-    FileId, Cancelable
+    Cancelable
 };
 
 pub(super) fn completions(
     acc: &mut Vec<CompletionItem>,
     db: &RootDatabase,
-    file_id: FileId,
+    source_root_id: SourceRootId,
+    module_tree: &ModuleTree,
+    module_id: ModuleId,
     file: &SourceFileNode,
     name_ref: ast::NameRef,
 ) -> Cancelable<()> {
@@ -28,14 +30,18 @@ pub(super) fn completions(
         Some(it) => it,
         None => return Ok(()),
     };
+
     match kind {
         NameRefKind::LocalRef => {
-            if let Some(fn_def) = complete_local_name(acc, &file, name_ref) {
+            let module_scope = db.module_scope(source_root_id, module_id)?;
+            if let Some(fn_def) = complete_local_name(acc, &module_scope, name_ref) {
                 complete_expr_keywords(&file, fn_def, name_ref, acc);
                 complete_expr_snippets(acc);
             }
         }
-        NameRefKind::CratePath(path) => complete_path(acc, db, file_id, path)?,
+        NameRefKind::CratePath(path) => {
+            complete_path(acc, db, source_root_id, module_tree, module_id, path)?
+        }
         NameRefKind::BareIdentInMod => {
             let name_range = name_ref.syntax().range();
             let top_node = name_ref
@@ -107,45 +113,26 @@ fn crate_path(mut path: ast::Path) -> Option<Vec<ast::NameRef>> {
 
 fn complete_local_name<'a>(
     acc: &mut Vec<CompletionItem>,
-    file: &SourceFileNode,
+    module_scope: &ModuleScope,
     name_ref: ast::NameRef<'a>,
 ) -> Option<ast::FnDef<'a>> {
-    let mut enclosing_fn = None;
-    for node in name_ref.syntax().ancestors() {
-        if let Some(items) = visitor()
-            .visit::<ast::SourceFile, _>(|it| Some(it.items()))
-            .visit::<ast::Module, _>(|it| Some(it.item_list()?.items()))
-            .accept(node)
-        {
-            if let Some(items) = items {
-                complete_module_items(file, items, Some(name_ref), acc);
-            }
-            break;
-        } else if enclosing_fn.is_none() {
-            if let Some(fn_def) = ast::FnDef::cast(node) {
-                enclosing_fn = Some(fn_def);
-                let scopes = FnScopes::new(fn_def);
-                complete_fn(name_ref, &scopes, acc);
-            }
-        }
+    let enclosing_fn = name_ref
+        .syntax()
+        .ancestors()
+        .take_while(|it| it.kind() != SOURCE_FILE && it.kind() != MODULE)
+        .find_map(ast::FnDef::cast);
+    if let Some(fn_def) = enclosing_fn {
+        let scopes = FnScopes::new(fn_def);
+        complete_fn(name_ref, &scopes, acc);
     }
-    enclosing_fn
-}
 
-fn complete_module_items(
-    file: &SourceFileNode,
-    items: AstChildren<ast::ModuleItem>,
-    this_item: Option<ast::NameRef>,
-    acc: &mut Vec<CompletionItem>,
-) {
-    let scope = ModuleScope::new(items); // FIXME
     acc.extend(
-        scope
+        module_scope
             .entries()
             .iter()
             .filter(|entry| {
-                let syntax = entry.ptr().resolve(file);
-                Some(syntax.borrowed()) != this_item.map(|it| it.syntax())
+                // Don't expose this item
+                !entry.ptr().range().is_subrange(&name_ref.syntax().range())
             })
             .map(|entry| CompletionItem {
                 label: entry.name().to_string(),
@@ -153,6 +140,7 @@ fn complete_module_items(
                 snippet: None,
             }),
     );
+    enclosing_fn
 }
 
 fn complete_fn(name_ref: ast::NameRef, scopes: &FnScopes, acc: &mut Vec<CompletionItem>) {
@@ -180,16 +168,12 @@ fn complete_fn(name_ref: ast::NameRef, scopes: &FnScopes, acc: &mut Vec<Completi
 fn complete_path(
     acc: &mut Vec<CompletionItem>,
     db: &RootDatabase,
-    file_id: FileId,
+    source_root_id: SourceRootId,
+    module_tree: &ModuleTree,
+    module_id: ModuleId,
     crate_path: Vec<ast::NameRef>,
 ) -> Cancelable<()> {
-    let source_root_id = db.file_source_root(file_id);
-    let module_tree = db.module_tree(source_root_id)?;
-    let module_id = match module_tree.any_module_for_source(ModuleSource::SourceFile(file_id)) {
-        None => return Ok(()),
-        Some(it) => it,
-    };
-    let target_module_id = match find_target_module(&module_tree, module_id, crate_path) {
+    let target_module_id = match find_target_module(module_tree, module_id, crate_path) {
         None => return Ok(()),
         Some(it) => it,
     };
@@ -327,5 +311,3 @@ fn complete_expr_snippets(acc: &mut Vec<CompletionItem>) {
         snippet: Some("eprintln!(\"$0 = {:#?}\", $0);".to_string()),
     });
 }
-
-
diff --git a/crates/ra_analysis/src/descriptors/module/mod.rs b/crates/ra_analysis/src/descriptors/module/mod.rs
index 58d6abed3..bc1148b22 100644
--- a/crates/ra_analysis/src/descriptors/module/mod.rs
+++ b/crates/ra_analysis/src/descriptors/module/mod.rs
@@ -3,7 +3,7 @@ pub(crate) mod scope;
 
 use ra_syntax::{
     ast::{self, AstNode, NameOwner},
-    SmolStr, SyntaxNode,
+    SmolStr, SyntaxNode, SyntaxNodeRef,
 };
 use relative_path::RelativePathBuf;
 
@@ -154,6 +154,16 @@ struct ModuleData {
 }
 
 impl ModuleSource {
+    pub(crate) fn for_node(file_id: FileId, node: SyntaxNodeRef) -> ModuleSource {
+        for node in node.ancestors() {
+            if let Some(m) = ast::Module::cast(node) {
+                if !m.has_semi() {
+                    return ModuleSource::new_inline(file_id, m);
+                }
+            }
+        }
+        ModuleSource::SourceFile(file_id)
+    }
     pub(crate) fn new_inline(file_id: FileId, module: ast::Module) -> ModuleSource {
         assert!(!module.has_semi());
         let ptr = SyntaxPtr::new(file_id, module.syntax());
diff --git a/crates/ra_analysis/src/descriptors/module/scope.rs b/crates/ra_analysis/src/descriptors/module/scope.rs
index 5fcbc3cb0..4490228e4 100644
--- a/crates/ra_analysis/src/descriptors/module/scope.rs
+++ b/crates/ra_analysis/src/descriptors/module/scope.rs
@@ -25,7 +25,7 @@ enum EntryKind {
 }
 
 impl ModuleScope {
-    pub(crate) fn new<'a>(items: impl Iterator<Item = ast::ModuleItem<'a>>) -> ModuleScope {
+    pub(super) fn new<'a>(items: impl Iterator<Item = ast::ModuleItem<'a>>) -> ModuleScope {
         let mut entries = Vec::new();
         for item in items {
             let entry = match item {
diff --git a/crates/ra_analysis/src/syntax_ptr.rs b/crates/ra_analysis/src/syntax_ptr.rs
index e45934ce0..194b94584 100644
--- a/crates/ra_analysis/src/syntax_ptr.rs
+++ b/crates/ra_analysis/src/syntax_ptr.rs
@@ -62,6 +62,11 @@ impl LocalSyntaxPtr {
             local: self,
         }
     }
+
+    // Seems unfortunate to expose
+    pub(crate) fn range(self) -> TextRange {
+        self.range
+    }
 }
 
 #[test]