Simplify Assists interface

Instead of building a physical tree structure, just "tag" related
assists with the same group

1 files changed, 48 insertions, 28 deletions

diff --git a/crates/ra_lsp_server/src/main_loop/handlers.rs b/crates/ra_lsp_server/src/main_loop/handlers.rs
index 282f6e8fc..65e8bc856 100644
--- a/crates/ra_lsp_server/src/main_loop/handlers.rs
+++ b/crates/ra_lsp_server/src/main_loop/handlers.rs
@@ -2,20 +2,21 @@
 //! The majority of requests are fulfilled by calling into the `ra_ide` crate.
 
 use std::{
+    collections::hash_map::Entry,
     fmt::Write as _,
     io::Write as _,
     process::{self, Stdio},
 };
 
-use either::Either;
 use lsp_server::ErrorCode;
 use lsp_types::{
     CallHierarchyIncomingCall, CallHierarchyIncomingCallsParams, CallHierarchyItem,
     CallHierarchyOutgoingCall, CallHierarchyOutgoingCallsParams, CallHierarchyPrepareParams,
-    CodeAction, CodeActionResponse, CodeLens, Command, CompletionItem, Diagnostic,
-    DocumentFormattingParams, DocumentHighlight, DocumentSymbol, FoldingRange, FoldingRangeParams,
-    Hover, HoverContents, Location, MarkupContent, MarkupKind, Position, PrepareRenameResponse,
-    Range, RenameParams, SymbolInformation, TextDocumentIdentifier, TextEdit, WorkspaceEdit,
+    CodeAction, CodeActionOrCommand, CodeActionResponse, CodeLens, Command, CompletionItem,
+    Diagnostic, DocumentFormattingParams, DocumentHighlight, DocumentSymbol, FoldingRange,
+    FoldingRangeParams, Hover, HoverContents, Location, MarkupContent, MarkupKind, Position,
+    PrepareRenameResponse, Range, RenameParams, SymbolInformation, TextDocumentIdentifier,
+    TextEdit, WorkspaceEdit,
 };
 use ra_ide::{
     AssistId, FileId, FilePosition, FileRange, Query, RangeInfo, Runnable, RunnableKind,
@@ -685,34 +686,53 @@ pub fn handle_code_action(
         res.push(fix.action.clone());
     }
 
+    let mut groups = FxHashMap::default();
     for assist in world.analysis().assists(FileRange { file_id, range })?.into_iter() {
-        let title = assist.label.clone();
+        let arg = to_value(assist.source_change.try_conv_with(&world)?)?;
+
+        let (command, title, arg) = match assist.group_label {
+            None => ("rust-analyzer.applySourceChange", assist.label.clone(), arg),
+
+            // Group all assists with the same `group_label` into a single CodeAction.
+            Some(group_label) => {
+                match groups.entry(group_label.clone()) {
+                    Entry::Occupied(entry) => {
+                        let idx: usize = *entry.get();
+                        match &mut res[idx] {
+                            CodeActionOrCommand::CodeAction(CodeAction {
+                                command: Some(Command { arguments: Some(arguments), .. }),
+                                ..
+                            }) => match arguments.as_mut_slice() {
+                                [serde_json::Value::Array(arguments)] => arguments.push(arg),
+                                _ => panic!("invalid group"),
+                            },
+                            _ => panic!("invalid group"),
+                        }
+                        continue;
+                    }
+                    Entry::Vacant(entry) => {
+                        entry.insert(res.len());
+                    }
+                }
+                ("rust-analyzer.selectAndApplySourceChange", group_label, to_value(vec![arg])?)
+            }
+        };
 
-        let command = match assist.change_data {
-            Either::Left(change) => Command {
-                title,
-                command: "rust-analyzer.applySourceChange".to_string(),
-                arguments: Some(vec![to_value(change.try_conv_with(&world)?)?]),
-            },
-            Either::Right(changes) => Command {
-                title,
-                command: "rust-analyzer.selectAndApplySourceChange".to_string(),
-                arguments: Some(vec![to_value(
-                    changes
-                        .into_iter()
-                        .map(|change| change.try_conv_with(&world))
-                        .collect::<Result<Vec<_>>>()?,
-                )?]),
-            },
+        let command = Command {
+            title: assist.label.clone(),
+            command: command.to_string(),
+            arguments: Some(vec![arg]),
+        };
+
+        let kind = match assist.id {
+            AssistId("introduce_variable") => Some("refactor.extract.variable".to_string()),
+            AssistId("add_custom_impl") => Some("refactor.rewrite.add_custom_impl".to_string()),
+            _ => None,
         };
 
         let action = CodeAction {
-            title: command.title.clone(),
-            kind: match assist.id {
-                AssistId("introduce_variable") => Some("refactor.extract.variable".to_string()),
-                AssistId("add_custom_impl") => Some("refactor.rewrite.add_custom_impl".to_string()),
-                _ => None,
-            },
+            title,
+            kind,
             diagnostics: None,
             edit: None,
             command: Some(command),