Code actions for attribute accessor creation

lib/ruby_lsp/requests/code_action_resolve.rb

@@ -42,6 +42,10 @@ def perform
           refactor_method
         when CodeActions::TOGGLE_BLOCK_STYLE_TITLE
           switch_block_style
+        when CodeActions::CREATE_ATTRIBUTE_READER,
+             CodeActions::CREATE_ATTRIBUTE_WRITER,
+             CodeActions::CREATE_ATTRIBUTE_ACCESSOR
+          create_attribute_accessor
         else
           Error::UnknownCodeAction
         end
@@ -325,6 +329,90 @@ def switch_block_body(body, indentation)
 
         indentation ? body_content.gsub(";", "\n") : "#{body_content.gsub("\n", ";")} "
       end
+
+      sig { returns(T.any(Interface::CodeAction, Error)) }
+      def create_attribute_accessor
+        source_range = @code_action.dig(:data, :range)
+
+        node = if source_range[:start] != source_range[:end]
+          @document.locate_first_within_range(
+            @code_action.dig(:data, :range),
+            node_types: CodeActions::INSTANCE_VARIABLE_NODES,
+          )
+        end
+
+        if node.nil?
+          node_context = @document.locate_node(
+            source_range[:start],
+            node_types: CodeActions::INSTANCE_VARIABLE_NODES,
+          )
+          node = node_context.node
+
+          return Error::EmptySelection unless CodeActions::INSTANCE_VARIABLE_NODES.include?(node.class)
+        end
+
+        node = T.cast(
+          node,
+          T.any(
+            Prism::InstanceVariableAndWriteNode,
+            Prism::InstanceVariableOperatorWriteNode,
+            Prism::InstanceVariableOrWriteNode,
+            Prism::InstanceVariableReadNode,
+            Prism::InstanceVariableTargetNode,
+            Prism::InstanceVariableWriteNode,
+          ),
+        )
+
+        node_context = @document.locate_node(
+          {
+            line: node.location.start_line,
+            character: node.location.start_character_column,
+          },
+          node_types: [
+            Prism::ClassNode,
+            Prism::ModuleNode,
+            Prism::SingletonClassNode,
+          ],
+        )
+        closest_node = node_context.node
+        return Error::InvalidTargetRange if closest_node.nil?
+
+        attribute_name = node.name[1..]
+        indentation = " " * (closest_node.location.start_column + 2)
+        attribute_accessor_source = T.must(
+          case @code_action[:title]
+          when CodeActions::CREATE_ATTRIBUTE_READER
+            "#{indentation}attr_reader :#{attribute_name}\n\n"
+          when CodeActions::CREATE_ATTRIBUTE_WRITER
+            "#{indentation}attr_writer :#{attribute_name}\n\n"
+          when CodeActions::CREATE_ATTRIBUTE_ACCESSOR
+            "#{indentation}attr_accessor :#{attribute_name}\n\n"
+          end,
+        )
+
+        target_start_line = closest_node.location.start_line
+        target_range = {
+          start: { line: target_start_line, character: 0 },
+          end: { line: target_start_line, character: 0 },
+        }
+
+        Interface::CodeAction.new(
+          title: @code_action[:title],
+          edit: Interface::WorkspaceEdit.new(
+            document_changes: [
+              Interface::TextDocumentEdit.new(
+                text_document: Interface::OptionalVersionedTextDocumentIdentifier.new(
+                  uri: @code_action.dig(:data, :uri),
+                  version: nil,
+                ),
+                edits: [
+                  create_text_edit(target_range, attribute_accessor_source),
+                ],
+              ),
+            ],
+          ),
+        )
+      end
     end
   end
 end

lib/ruby_lsp/requests/code_actions.rb

@@ -12,6 +12,21 @@ class CodeActions < Request
       EXTRACT_TO_VARIABLE_TITLE = "Refactor: Extract Variable"
       EXTRACT_TO_METHOD_TITLE = "Refactor: Extract Method"
       TOGGLE_BLOCK_STYLE_TITLE = "Refactor: Toggle block style"
+      CREATE_ATTRIBUTE_READER = "Create Attribute Reader"
+      CREATE_ATTRIBUTE_WRITER = "Create Attribute Writer"
+      CREATE_ATTRIBUTE_ACCESSOR = "Create Attribute Accessor"
+
+      INSTANCE_VARIABLE_NODES = T.let(
+        [
+          Prism::InstanceVariableAndWriteNode,
+          Prism::InstanceVariableOperatorWriteNode,
+          Prism::InstanceVariableOrWriteNode,
+          Prism::InstanceVariableReadNode,
+          Prism::InstanceVariableTargetNode,
+          Prism::InstanceVariableWriteNode,
+        ],
+        T::Array[T.class_of(Prism::Node)],
+      )
 
       class << self
         extend T::Sig
@@ -66,9 +81,50 @@ def perform
             data: { range: @range, uri: @uri.to_s },
           )
         end
+        code_actions.concat(attribute_actions)
 
         code_actions
       end
+
+      private
+
+      sig { returns(T::Array[Interface::CodeAction]) }
+      def attribute_actions
+        return [] unless @document.is_a?(RubyDocument)
+
+        node = if @range.dig(:start) != @range.dig(:end)
+          @document.locate_first_within_range(
+            @range,
+            node_types: INSTANCE_VARIABLE_NODES,
+          )
+        end
+
+        if node.nil?
+          node_context = @document.locate_node(
+            @range[:start],
+            node_types: CodeActions::INSTANCE_VARIABLE_NODES,
+          )
+          return [] unless INSTANCE_VARIABLE_NODES.include?(node_context.node.class)
+        end
+
+        [
+          Interface::CodeAction.new(
+            title: CREATE_ATTRIBUTE_READER,
+            kind: Constant::CodeActionKind::EMPTY,
+            data: { range: @range, uri: @uri.to_s },
+          ),
+          Interface::CodeAction.new(
+            title: CREATE_ATTRIBUTE_WRITER,
+            kind: Constant::CodeActionKind::EMPTY,
+            data: { range: @range, uri: @uri.to_s },
+          ),
+          Interface::CodeAction.new(
+            title: CREATE_ATTRIBUTE_ACCESSOR,
+            kind: Constant::CodeActionKind::EMPTY,
+            data: { range: @range, uri: @uri.to_s },
+          ),
+        ]
+      end
     end
   end
 end

test/expectations/code_action_resolve/create_attribute_accessor.exp.json

@@ -0,0 +1,47 @@
+{
+  "params": {
+    "kind": "",
+    "title": "Create Attribute Accessor",
+    "data": {
+      "range": {
+        "start": {
+          "line": 2,
+          "character": 0
+        },
+        "end": {
+          "line": 2,
+          "character": 16
+        }
+      },
+      "uri": "file:///fake"
+    }
+  },
+  "result": {
+    "title": "Create Attribute Accessor",
+    "edit": {
+      "documentChanges": [
+        {
+          "textDocument": {
+            "uri": "file:///fake",
+            "version": null
+          },
+          "edits": [
+            {
+              "range": {
+                "start": {
+                  "line": 1,
+                  "character": 0
+                },
+                "end": {
+                  "line": 1,
+                  "character": 0
+                }
+              },
+              "newText":  "  attr_accessor :foo\n\n"
+            }
+          ]
+        }
+      ]
+    }
+  }
+}

test/expectations/code_action_resolve/create_attribute_accessor_without_surrounding_class.exp.json

@@ -0,0 +1,47 @@
+{
+  "params": {
+    "kind": "",
+    "title": "Create Attribute Accessor",
+    "data": {
+      "range": {
+        "start": {
+          "line": 0,
+          "character": 1
+        },
+        "end": {
+          "line": 0,
+          "character": 1
+        }
+      },
+      "uri": "file:///fake"
+    }
+  },
+  "result": {
+    "title": "Create Attribute Accessor",
+    "edit": {
+      "documentChanges": [
+        {
+          "textDocument": {
+            "uri": "file:///fake",
+            "version": null
+          },
+          "edits": [
+            {
+              "range": {
+                "start": {
+                  "line": 1,
+                  "character": 0
+                },
+                "end": {
+                  "line": 1,
+                  "character": 0
+                }
+              },
+              "newText": "  attr_accessor :foo\n\n"
+            }
+          ]
+        }
+      ]
+    }
+  }
+}

test/expectations/code_action_resolve/create_attribute_reader.exp.json

@@ -0,0 +1,47 @@
+{
+  "params": {
+    "kind": "",
+    "title": "Create Attribute Reader",
+    "data": {
+      "range": {
+        "start": {
+          "line": 2,
+          "character": 0
+        },
+        "end": {
+          "line": 2,
+          "character": 16
+        }
+      },
+      "uri": "file:///fake"
+    }
+  },
+  "result": {
+    "title": "Create Attribute Reader",
+    "edit": {
+      "documentChanges": [
+        {
+          "textDocument": {
+            "uri": "file:///fake",
+            "version": null
+          },
+          "edits": [
+            {
+              "range": {
+                "start": {
+                  "line": 1,
+                  "character": 0
+                },
+                "end": {
+                  "line": 1,
+                  "character": 0
+                }
+              },
+              "newText": "  attr_reader :foo\n\n"
+            }
+          ]
+        }
+      ]
+    }
+  }
+}

test/expectations/code_action_resolve/create_attribute_writer.exp.json

@@ -0,0 +1,47 @@
+{
+  "params": {
+    "kind": "",
+    "title": "Create Attribute Writer",
+    "data": {
+      "range": {
+        "start": {
+          "line": 3,
+          "character": 0
+        },
+        "end": {
+          "line": 4,
+          "character": 0
+        }
+      },
+      "uri": "file:///fake"
+    }
+  },
+  "result": {
+    "title": "Create Attribute Writer",
+    "edit": {
+      "documentChanges": [
+        {
+          "textDocument": {
+            "uri": "file:///fake",
+            "version": null
+          },
+          "edits": [
+            {
+              "range": {
+                "start": {
+                  "line": 2,
+                  "character": 0
+                },
+                "end": {
+                  "line": 2,
+                  "character": 0
+                }
+              },
+              "newText": "    attr_writer :foo\n\n"
+            }
+          ]
+        }
+      ]
+    }
+  }
+}