LSP: code action to preview a particular component

tools/lsp/main.rs

@@ -16,11 +16,12 @@ use std::path::Path;
 
 use lsp_server::{Connection, Message, Request, RequestId, Response};
 use lsp_types::notification::{DidChangeTextDocument, DidOpenTextDocument, Notification};
-use lsp_types::request::GotoDefinition;
+use lsp_types::request::{CodeActionRequest, ExecuteCommand, GotoDefinition};
 use lsp_types::request::{Completion, HoverRequest};
 use lsp_types::{
-    CompletionItem, CompletionItemKind, CompletionOptions, DidChangeTextDocumentParams,
-    DidOpenTextDocumentParams, GotoDefinitionResponse, Hover, HoverProviderCapability,
+    CodeActionOrCommand, CodeActionProviderCapability, Command, CompletionItem, CompletionItemKind,
+    CompletionOptions, DidChangeTextDocumentParams, DidOpenTextDocumentParams,
+    ExecuteCommandOptions, GotoDefinitionResponse, Hover, HoverProviderCapability,
     InitializeParams, LocationLink, OneOf, Position, PublishDiagnosticsParams, Range,
     ServerCapabilities, TextDocumentSyncCapability, Url, WorkDoneProgressOptions,
 };
@@ -33,6 +34,8 @@ use sixtyfps_compilerlib::{object_tree, CompilerConfiguration};
 
 type Error = Box<dyn std::error::Error>;
 
+const SHOW_PREVIEW_COMMAND: &str = "showPreview";
+
 struct DocumentCache<'a> {
     documents: TypeLoader<'a>,
     newline_offsets: HashMap<Url, Vec<u32>>,
@@ -76,7 +79,11 @@ fn run_lsp_server() -> Result<(), Error> {
         text_document_sync: Some(TextDocumentSyncCapability::Kind(
             lsp_types::TextDocumentSyncKind::Full,
         )),
-
+        code_action_provider: Some(CodeActionProviderCapability::Simple(true)),
+        execute_command_provider: Some(ExecuteCommandOptions {
+            commands: vec![SHOW_PREVIEW_COMMAND.into()],
+            ..Default::default()
+        }),
         ..ServerCapabilities::default()
     };
     let server_capabilities = serde_json::to_value(&capabilities).unwrap();
@@ -118,12 +125,20 @@ fn handle_request(
 ) -> Result<(), Error> {
     let mut req = Some(req);
     if let Some((id, params)) = cast::<GotoDefinition>(&mut req) {
-        let result = token_descr(document_cache, params.text_document_position_params)
+        let result = token_descr(
+            document_cache,
+            params.text_document_position_params.text_document,
+            params.text_document_position_params.position,
+        )
         .and_then(|token| goto_definition(document_cache, token.parent()));
         let resp = Response::new_ok(id, result);
         connection.sender.send(Message::Response(resp))?;
     } else if let Some((id, params)) = cast::<Completion>(&mut req) {
-        let result = token_descr(document_cache, params.text_document_position)
+        let result = token_descr(
+            document_cache,
+            params.text_document_position.text_document,
+            params.text_document_position.position,
+        )
         .and_then(|token| completion_at(document_cache, token.parent()));
         let resp = Response::new_ok(id, result);
         connection.sender.send(Message::Response(resp))?;
@@ -139,6 +154,18 @@ fn handle_request(
         let resp = Response::new_ok(id, result);
         connection.sender.send(Message::Response(resp))?;*/
         connection.sender.send(Message::Response(Response::new_ok(id, None::<Hover>)))?;
+    } else if let Some((id, params)) = cast::<CodeActionRequest>(&mut req) {
+        let result = token_descr(document_cache, params.text_document, params.range.start)
+            .and_then(|token| get_code_actions(document_cache, token.parent()));
+        connection.sender.send(Message::Response(Response::new_ok(id, result)))?;
+    } else if let Some((id, params)) = cast::<ExecuteCommand>(&mut req) {
+        match params.command.as_str() {
+            SHOW_PREVIEW_COMMAND => show_preview_command(&params.arguments, connection)?,
+            _ => (),
+        }
+        connection
+            .sender
+            .send(Message::Response(Response::new_ok(id, None::<serde_json::Value>)))?;
     };
     Ok(())
 }
@@ -180,21 +207,31 @@ fn handle_notification(
             )?;
         }
         "sixtyfps/showPreview" => {
+            show_preview_command(req.params.as_array().map_or(&[], |x| x.as_slice()), connection)?;
+        }
+        _ => (),
+    }
+    Ok(())
+}
+
+fn show_preview_command(
+    params: &[serde_json::Value],
+    connection: &Connection,
+) -> Result<(), Error> {
     let e = || -> Error { "InvalidParameter".into() };
-            let path = if let serde_json::Value::String(s) = req.params.get(0).ok_or_else(e)? {
+    let path = if let serde_json::Value::String(s) = params.get(0).ok_or_else(e)? {
         std::path::PathBuf::from(s)
     } else {
         return Err(e());
     };
     let path_canon = path.canonicalize().unwrap_or_else(|_| path.to_owned());
+    let component = params.get(1).and_then(|v| v.as_str()).map(|v| v.to_string());
     preview::load_preview(
         connection.sender.clone(),
         path_canon.into(),
+        component,
         preview::PostLoadBehavior::ShowAfterLoad,
     );
-        }
-        _ => (),
-    }
     Ok(())
 }
 
@@ -279,18 +316,14 @@ fn to_range(span: (usize, usize)) -> Range {
 }
 
 fn token_descr(
-    document_cache: &DocumentCache,
-    lsp_position: lsp_types::TextDocumentPositionParams,
+    document_cache: &mut DocumentCache,
+    text_document: lsp_types::TextDocumentIdentifier,
+    pos: Position,
 ) -> Option<sixtyfps_compilerlib::parser::SyntaxToken> {
-    let o = document_cache
-        .newline_offsets
-        .get(&lsp_position.text_document.uri)?
-        .get(lsp_position.position.line as usize)?
-        + lsp_position.position.character as u32;
+    let o = document_cache.newline_offsets.get(&text_document.uri)?.get(pos.line as usize)?
+        + pos.character as u32;
 
-    let doc = document_cache
-        .documents
-        .get_document(&lsp_position.text_document.uri.to_file_path().ok()?)?;
+    let doc = document_cache.documents.get_document(&text_document.uri.to_file_path().ok()?)?;
     let node = doc.node.as_ref()?;
     if !node.text_range().contains(o.into()) {
         return None;
@@ -379,6 +412,34 @@ fn goto_node(
     }]))
 }
 
+fn get_code_actions(
+    _document_cache: &mut DocumentCache,
+    node: SyntaxNode,
+) -> Option<Vec<CodeActionOrCommand>> {
+    let component = syntax_nodes::Component::new(node.clone())
+        .or_else(|| {
+            syntax_nodes::DeclaredIdentifier::new(node.clone())
+                .and_then(|n| n.parent())
+                .and_then(|p| syntax_nodes::Component::new(p))
+        })
+        .or_else(|| {
+            syntax_nodes::QualifiedName::new(node.clone())
+                .and_then(|n| n.parent())
+                .and_then(|p| syntax_nodes::Element::new(p))
+                .and_then(|n| n.parent())
+                .and_then(|p| syntax_nodes::Component::new(p))
+        })?;
+
+    let component_name =
+        sixtyfps_compilerlib::parser::identifier_text(&component.DeclaredIdentifier())?;
+
+    Some(vec![CodeActionOrCommand::Command(Command::new(
+        "Show preview".into(),
+        SHOW_PREVIEW_COMMAND.into(),
+        Some(vec![component.source_file.path().to_string_lossy().into(), component_name.into()]),
+    ))])
+}
+
 fn completion_at(document_cache: &DocumentCache, token: SyntaxNode) -> Option<Vec<CompletionItem>> {
     match token.kind() {
         SyntaxKind::Element => {

tools/lsp/preview.rs

@@ -68,11 +68,12 @@ pub enum PostLoadBehavior {
 pub fn load_preview(
     sender: crossbeam_channel::Sender<Message>,
     path: std::path::PathBuf,
+    component: Option<String>,
     post_load_behavior: PostLoadBehavior,
 ) {
-    run_in_ui_thread(Box::pin(
-        async move { reload_preview(sender, &path, post_load_behavior).await },
-    ));
+    run_in_ui_thread(Box::pin(async move {
+        reload_preview(sender, &path, component, post_load_behavior).await
+    }));
 }
 
 #[derive(Default)]
@@ -80,6 +81,7 @@ struct ContentCache {
     source_code: HashMap<PathBuf, String>,
     dependency: HashSet<PathBuf>,
     current_root: PathBuf,
+    current_component: Option<String>,
     sender: Option<crossbeam_channel::Sender<Message>>,
 }
 
@@ -91,10 +93,11 @@ pub fn set_contents(path: &Path, content: String) {
     cache.source_code.insert(path.to_owned(), content);
     if cache.dependency.contains(path) {
         let current_root = cache.current_root.clone();
+        let current_component = cache.current_component.clone();
         let sender = cache.sender.take();
         drop(cache);
         if let Some(sender) = sender {
-            load_preview(sender, current_root, PostLoadBehavior::DoNothing);
+            load_preview(sender, current_root, current_component, PostLoadBehavior::DoNothing);
         }
     }
 }
@@ -111,6 +114,7 @@ fn get_file_from_cache(path: PathBuf) -> Option<String> {
 async fn reload_preview(
     sender: crossbeam_channel::Sender<Message>,
     path: &std::path::Path,
+    component: Option<String>,
     post_load_behavior: PostLoadBehavior,
 ) {
     send_notification(&sender, "Loading Preview…", Health::Ok);
@@ -127,7 +131,19 @@ async fn reload_preview(
         Box::pin(async move { get_file_from_cache(path).map(Result::Ok) })
     });
 
-    let compiled = if let Some(from_cache) = get_file_from_cache(path.to_owned()) {
+    let compiled = if let Some(mut from_cache) = get_file_from_cache(path.to_owned()) {
+        if let Some(component) = component {
+            from_cache = format!(
+                r#"{}
+_Preview := Window {{
+    {} {{
+        width <=> root.width;
+        height <=> root.height;
+    }}
+}}"#,
+                from_cache, component
+            );
+        }
         builder.build_from_source(from_cache, path.to_owned()).await
     } else {
         builder.build_from_path(path).await