Merge pull request #2103 from Shopify/atvs-types-hierarchy

Add support for type hierarchy requests

lib/ruby_lsp/requests.rb

@@ -47,6 +47,8 @@ module Requests
     autoload :ShowSyntaxTree, "ruby_lsp/requests/show_syntax_tree"
     autoload :WorkspaceSymbol, "ruby_lsp/requests/workspace_symbol"
     autoload :SignatureHelp, "ruby_lsp/requests/signature_help"
+    autoload :PrepareTypeHierarchy, "ruby_lsp/requests/prepare_type_hierarchy"
+    autoload :TypeHierarchySupertypes, "ruby_lsp/requests/type_hierarchy_supertypes"
 
     # :nodoc:
     module Support

lib/ruby_lsp/requests/prepare_type_hierarchy.rb

@@ -0,0 +1,88 @@
+# typed: strict
+# frozen_string_literal: true
+
+module RubyLsp
+  module Requests
+    # ![Prepare type hierarchy demo](../../prepare_type_hierarchy.gif)
+    #
+    # The [prepare type hierarchy
+    # request](https://microsoft.github.io/language-server-protocol/specification#textDocument_prepareTypeHierarchy)
+    # displays the list of ancestors (supertypes) and descendants (subtypes) for the selected type.
+    #
+    # Currently only supports supertypes due to a limitation of the index.
+    #
+    # # Example
+    #
+    # ```ruby
+    # class Foo; end
+    # class Bar < Foo; end
+    #
+    # puts Bar # <-- right click on `Bar` and select "Show Type Hierarchy"
+    # ```
+    class PrepareTypeHierarchy < Request
+      extend T::Sig
+
+      include Support::Common
+
+      class << self
+        extend T::Sig
+
+        sig { returns(Interface::TypeHierarchyOptions) }
+        def provider
+          Interface::TypeHierarchyOptions.new
+        end
+      end
+
+      sig do
+        params(
+          document: Document,
+          index: RubyIndexer::Index,
+          position: T::Hash[Symbol, T.untyped],
+        ).void
+      end
+      def initialize(document, index, position)
+        super()
+
+        @document = document
+        @index = index
+        @position = position
+      end
+
+      sig { override.returns(T.nilable(T::Array[Interface::TypeHierarchyItem])) }
+      def perform
+        context = @document.locate_node(
+          @position,
+          node_types: [
+            Prism::ConstantReadNode,
+            Prism::ConstantWriteNode,
+            Prism::ConstantPathNode,
+          ],
+        )
+
+        node = context.node
+        parent = context.parent
+        return unless node && parent
+
+        target = determine_target(node, parent, @position)
+        entries = @index.resolve(target.slice, context.nesting)
+        return unless entries
+
+        # While the spec allows for multiple entries, VSCode seems to only support one
+        # We'll just return the first one for now
+        first_entry = T.must(entries.first)
+
+        range = range_from_location(first_entry.location)
+
+        [
+          Interface::TypeHierarchyItem.new(
+            name: first_entry.name,
+            kind: kind_for_entry(first_entry),
+            uri: URI::Generic.from_path(path: first_entry.file_path).to_s,
+            range: range,
+            selection_range: range,
+          ),
+        ]
+      end
+    end
+  end
+end

lib/ruby_lsp/requests/support/common.rb

@@ -26,7 +26,7 @@ def range_from_node(node)
           )
         end
 
-        sig { params(location: Prism::Location).returns(Interface::Range) }
+        sig { params(location: T.any(Prism::Location, RubyIndexer::Location)).returns(Interface::Range) }
         def range_from_location(location)
           Interface::Range.new(
             start: Interface::Position.new(
@@ -186,6 +186,24 @@ def each_constant_path_part(node, &block)
             current = current.parent
           end
         end
+
+        sig { params(entry: RubyIndexer::Entry).returns(T.nilable(Integer)) }
+        def kind_for_entry(entry)
+          case entry
+          when RubyIndexer::Entry::Class
+            Constant::SymbolKind::CLASS
+          when RubyIndexer::Entry::Module
+            Constant::SymbolKind::NAMESPACE
+          when RubyIndexer::Entry::Constant
+            Constant::SymbolKind::CONSTANT
+          when RubyIndexer::Entry::Method
+            entry.name == "initialize" ? Constant::SymbolKind::CONSTRUCTOR : Constant::SymbolKind::METHOD
+          when RubyIndexer::Entry::Accessor
+            Constant::SymbolKind::PROPERTY
+          when RubyIndexer::Entry::InstanceVariable
+            Constant::SymbolKind::FIELD
+          end
+        end
       end
     end
   end

lib/ruby_lsp/requests/type_hierarchy_supertypes.rb

@@ -0,0 +1,91 @@
+# typed: strict
+# frozen_string_literal: true
+
+module RubyLsp
+  module Requests
+    # ![Type hierarchy supertypes demo](../../type_hierarchy_supertypes.gif)
+    #
+    # The [type hierarchy supertypes
+    # request](https://microsoft.github.io/language-server-protocol/specification#typeHierarchy_supertypes)
+    # displays the list of ancestors (supertypes) for the selected type.
+    #
+    # # Example
+    #
+    # ```ruby
+    # class Foo; end
+    # class Bar < Foo; end
+    #
+    # puts Bar # <-- right click on `Bar` and select "Show Type Hierarchy"
+    # ```
+    class TypeHierarchySupertypes < Request
+      extend T::Sig
+
+      include Support::Common
+
+      sig { params(index: RubyIndexer::Index, item: T::Hash[Symbol, T.untyped]).void }
+      def initialize(index, item)
+        super()
+
+        @index = index
+        @item = item
+      end
+
+      sig { override.returns(T.nilable(T::Array[Interface::TypeHierarchyItem])) }
+      def perform
+        name = @item[:name]
+        entries = @index[name]
+
+        parents = T.let(Set.new, T::Set[RubyIndexer::Entry::Namespace])
+        return unless entries&.any?
+
+        entries.each do |entry|
+          next unless entry.is_a?(RubyIndexer::Entry::Namespace)
+
+          if entry.is_a?(RubyIndexer::Entry::Class)
+            parent_class_name = entry.parent_class
+            if parent_class_name
+              resolved_parent_entries = @index.resolve(parent_class_name, entry.nesting)
+              resolved_parent_entries&.each do |entry|
+                next unless entry.is_a?(RubyIndexer::Entry::Class)
+
+                parents << entry
+              end
+            end
+          end
+
+          entry.mixin_operations.each do |mixin_operation|
+            next if mixin_operation.is_a?(RubyIndexer::Entry::Extend)
+
+            mixin_name = mixin_operation.module_name
+            resolved_mixin_entries = @index.resolve(mixin_name, entry.nesting)
+            next unless resolved_mixin_entries
+
+            resolved_mixin_entries.each do |mixin_entry|
+              next unless mixin_entry.is_a?(RubyIndexer::Entry::Module)
+
+              parents << mixin_entry
+            end
+          end
+        end
+
+        parents.map { |entry| hierarchy_item(entry) }
+      end
+
+      private
+
+      sig { params(entry: RubyIndexer::Entry).returns(Interface::TypeHierarchyItem) }
+      def hierarchy_item(entry)
+        range = range_from_location(entry.location)
+
+        Interface::TypeHierarchyItem.new(
+          name: entry.name,
+          kind: kind_for_entry(entry),
+          uri: URI::Generic.from_path(path: entry.file_path).to_s,
+          range: range,
+          selection_range: range,
+          detail: entry.file_name,
+        )
+      end
+    end
+  end
+end

lib/ruby_lsp/requests/workspace_symbol.rb

@@ -64,26 +64,6 @@ def perform
           )
         end
       end
-
-      private
-
-      sig { params(entry: RubyIndexer::Entry).returns(T.nilable(Integer)) }
-      def kind_for_entry(entry)
-        case entry
-        when RubyIndexer::Entry::Class
-          Constant::SymbolKind::CLASS
-        when RubyIndexer::Entry::Module
-          Constant::SymbolKind::NAMESPACE
-        when RubyIndexer::Entry::Constant
-          Constant::SymbolKind::CONSTANT
-        when RubyIndexer::Entry::Method
-          entry.name == "initialize" ? Constant::SymbolKind::CONSTRUCTOR : Constant::SymbolKind::METHOD
-        when RubyIndexer::Entry::Accessor
-          Constant::SymbolKind::PROPERTY
-        when RubyIndexer::Entry::InstanceVariable
-          Constant::SymbolKind::FIELD
-        end
-      end
     end
   end
 end

lib/ruby_lsp/server.rb

@@ -68,6 +68,12 @@ def process_message(message)
         text_document_signature_help(message)
       when "textDocument/definition"
         text_document_definition(message)
+      when "textDocument/prepareTypeHierarchy"
+        text_document_prepare_type_hierarchy(message)
+      when "typeHierarchy/supertypes"
+        type_hierarchy_supertypes(message)
+      when "typeHierarchy/subtypes"
+        type_hierarchy_subtypes(message)
       when "workspace/didChangeWatchedFiles"
         workspace_did_change_watched_files(message)
       when "workspace/symbol"
@@ -162,6 +168,7 @@ def run_initialize(message)
       inlay_hint_provider = Requests::InlayHints.provider if enabled_features["inlayHint"]
       completion_provider = Requests::Completion.provider if enabled_features["completion"]
       signature_help_provider = Requests::SignatureHelp.provider if enabled_features["signatureHelp"]
+      type_hierarchy_provider = Requests::PrepareTypeHierarchy.provider if enabled_features["typeHierarchy"]
 
       response = {
         capabilities: Interface::ServerCapabilities.new(
@@ -187,6 +194,7 @@ def run_initialize(message)
           definition_provider: enabled_features["definition"],
           workspace_symbol_provider: enabled_features["workspaceSymbol"] && !@global_state.has_type_checker,
           signature_help_provider: signature_help_provider,
+          type_hierarchy_provider: type_hierarchy_provider,
           experimental: {
             addon_detection: true,
           },
@@ -673,6 +681,33 @@ def text_document_show_syntax_tree(message)
       send_message(Result.new(id: message[:id], response: response))
     end
 
+    sig { params(message: T::Hash[Symbol, T.untyped]).void }
+    def text_document_prepare_type_hierarchy(message)
+      params = message[:params]
+      response = Requests::PrepareTypeHierarchy.new(
+        @store.get(params.dig(:textDocument, :uri)),
+        @global_state.index,
+        params[:position],
+      ).perform
+      send_message(Result.new(id: message[:id], response: response))
+    end
+
+    sig { params(message: T::Hash[Symbol, T.untyped]).void }
+    def type_hierarchy_supertypes(message)
+      response = Requests::TypeHierarchySupertypes.new(
+        @global_state.index,
+        message.dig(:params, :item),
+      ).perform
+      send_message(Result.new(id: message[:id], response: response))
+    end
+
+    sig { params(message: T::Hash[Symbol, T.untyped]).void }
+    def type_hierarchy_subtypes(message)
+      # TODO: implement subtypes
+      # The current index representation doesn't allow us to find the children of an entry.
+      send_message(Result.new(id: message[:id], response: nil))
+    end
+
     sig { params(message: T::Hash[Symbol, T.untyped]).void }
     def workspace_dependencies(message)
       response = begin