Auto indent after end keyword (#1014)

* audo indent after end keyword

* fix code review appointments

* fix sorbet appointments

* solve code review appointments

* code review updates

* add sorbet signature

* solve linter report problems

lib/ruby_lsp/executor.rb

@@ -670,7 +670,7 @@ def initialize_request(options)
       on_type_formatting_provider = if enabled_features["onTypeFormatting"]
         Interface::DocumentOnTypeFormattingOptions.new(
           first_trigger_character: "{",
-          more_trigger_character: ["\n", "|"],
+          more_trigger_character: ["\n", "|", "d"],
         )
       end
 

lib/ruby_lsp/requests/on_type_formatting.rb

@@ -60,6 +60,8 @@ def run
               handle_statement_end
             end
           end
+        when "d"
+          auto_indent_after_end_keyword
         end
 
         @edits
@@ -185,6 +187,32 @@ def find_indentation(line)
 
         count
       end
+
+      sig { void }
+      def auto_indent_after_end_keyword
+        current_line = @lines[@position[:line]]
+        return unless current_line&.strip == "end"
+
+        target, _parent, _nesting = @document.locate_node({
+          line: @position[:line],
+          character: @position[:character] - 1,
+        })
+
+        statements = case target
+        when Prism::IfNode, Prism::UnlessNode, Prism::ForNode, Prism::WhileNode, Prism::UntilNode
+          target.statements
+        end
+        return unless statements
+
+        statements.body.each do |node|
+          loc = node.location
+          next unless loc.start_column == @indentation
+
+          add_edit_with_text("  ", { line: loc.start_line - 1, character: 0 })
+        end
+
+        move_cursor_to(@position[:line], @position[:character])
+      end
     end
   end
 end

test/requests/on_type_formatting_test.rb

@@ -352,6 +352,24 @@ def test_breaking_line_immediately_after_keyword
     assert_equal(expected_edits.to_json, T.must(edits).to_json)
   end
 
+  def test_auto_indent_after_end_keyword
+    document = RubyLsp::RubyDocument.new(source: +"if foo\nbar\nend", version: 1, uri: URI("file:///fake.rb"))
+    edits = RubyLsp::Requests::OnTypeFormatting.new(document, { line: 2, character: 2 }, "d").run
+
+    expected_edits = [
+      {
+        range: { start: { line: 1, character: 0 }, end: { line: 1, character: 0 } },
+        newText: "  ",
+      },
+      {
+        range: { start: { line: 2, character: 2 }, end: { line: 2, character: 2 } },
+        newText: "$0",
+      },
+    ]
+
+    assert_equal(expected_edits.to_json, T.must(edits).to_json)
+  end
+
   def test_breaking_line_if_a_keyword_is_part_of_method_call
     document = RubyLsp::RubyDocument.new(source: +"  force({", version: 1, uri: URI("file:///fake.rb"))
     edits = RubyLsp::Requests::OnTypeFormatting.new(document, { line: 1, character: 2 }, "\n").run