5 files changed, 46 insertions, 0 deletions

diff --git a/crates/ide/src/lib.rs b/crates/ide/src/lib.rs
index f4b90db3a..ff2a54117 100644
--- a/crates/ide/src/lib.rs
+++ b/crates/ide/src/lib.rs
@@ -50,6 +50,7 @@ mod typing;
 mod markdown_remove;
 mod doc_links;
 mod view_crate_graph;
+mod view_item_tree;
 
 use std::sync::Arc;
 
@@ -288,6 +289,10 @@ impl Analysis {
         self.with_db(|db| view_hir::view_hir(&db, position))
     }
 
+    pub fn view_item_tree(&self, file_id: FileId) -> Cancelable<String> {
+        self.with_db(|db| view_item_tree::view_item_tree(&db, file_id))
+    }
+
     /// Renders the crate graph to GraphViz "dot" syntax.
     pub fn view_crate_graph(&self) -> Cancelable<Result<String, String>> {
         self.with_db(|db| view_crate_graph::view_crate_graph(&db))
diff --git a/crates/ide/src/view_item_tree.rs b/crates/ide/src/view_item_tree.rs
new file mode 100644
index 000000000..3dc03085d
--- /dev/null
+++ b/crates/ide/src/view_item_tree.rs
@@ -0,0 +1,16 @@
+use hir::db::DefDatabase;
+use ide_db::base_db::FileId;
+use ide_db::RootDatabase;
+
+// Feature: Debug ItemTree
+//
+// Displays the ItemTree of the currently open file, for debugging.
+//
+// |===
+// | Editor  | Action Name
+//
+// | VS Code | **Rust Analyzer: Debug ItemTree**
+// |===
+pub(crate) fn view_item_tree(db: &RootDatabase, file_id: FileId) -> String {
+    db.file_item_tree(file_id.into()).pretty_print()
+}
diff --git a/crates/rust-analyzer/src/handlers.rs b/crates/rust-analyzer/src/handlers.rs
index 51041d7a0..aa12fd94b 100644
--- a/crates/rust-analyzer/src/handlers.rs
+++ b/crates/rust-analyzer/src/handlers.rs
@@ -117,6 +117,16 @@ pub(crate) fn handle_view_hir(
     Ok(res)
 }
 
+pub(crate) fn handle_view_item_tree(
+    snap: GlobalStateSnapshot,
+    params: lsp_ext::ViewItemTreeParams,
+) -> Result<String> {
+    let _p = profile::span("handle_view_item_tree");
+    let file_id = from_proto::file_id(&snap, &params.text_document.uri)?;
+    let res = snap.analysis.view_item_tree(file_id)?;
+    Ok(res)
+}
+
 pub(crate) fn handle_view_crate_graph(snap: GlobalStateSnapshot, (): ()) -> Result<String> {
     let _p = profile::span("handle_view_crate_graph");
     let dot = snap.analysis.view_crate_graph()??;
diff --git a/crates/rust-analyzer/src/lsp_ext.rs b/crates/rust-analyzer/src/lsp_ext.rs
index 34b53a7a8..905048793 100644
--- a/crates/rust-analyzer/src/lsp_ext.rs
+++ b/crates/rust-analyzer/src/lsp_ext.rs
@@ -70,6 +70,20 @@ impl Request for ViewCrateGraph {
     const METHOD: &'static str = "rust-analyzer/viewCrateGraph";
 }
 
+#[derive(Deserialize, Serialize, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct ViewItemTreeParams {
+    pub text_document: TextDocumentIdentifier,
+}
+
+pub enum ViewItemTree {}
+
+impl Request for ViewItemTree {
+    type Params = ViewItemTreeParams;
+    type Result = String;
+    const METHOD: &'static str = "rust-analyzer/viewItemTree";
+}
+
 pub enum ExpandMacro {}
 
 impl Request for ExpandMacro {
diff --git a/crates/rust-analyzer/src/main_loop.rs b/crates/rust-analyzer/src/main_loop.rs
index 4e0791611..f837b89dd 100644
--- a/crates/rust-analyzer/src/main_loop.rs
+++ b/crates/rust-analyzer/src/main_loop.rs
@@ -514,6 +514,7 @@ impl GlobalState {
             .on::<lsp_ext::SyntaxTree>(handlers::handle_syntax_tree)
             .on::<lsp_ext::ViewHir>(handlers::handle_view_hir)
             .on::<lsp_ext::ViewCrateGraph>(handlers::handle_view_crate_graph)
+            .on::<lsp_ext::ViewItemTree>(handlers::handle_view_item_tree)
             .on::<lsp_ext::ExpandMacro>(handlers::handle_expand_macro)
             .on::<lsp_ext::ParentModule>(handlers::handle_parent_module)
             .on::<lsp_ext::Runnables>(handlers::handle_runnables)