[WIP] Handle all modules extending NodePattern::Macros

Author: sambostock

lib/tapioca/dsl/compilers/rubocop.rb

@@ -1,11 +1,7 @@
 # typed: strict
 # frozen_string_literal: true
 
-begin
-  require "rubocop"
-rescue LoadError
-  return
-end
+return unless defined?(RuboCop::AST::NodePattern::Macros)
 
 module Tapioca
   module Dsl
@@ -34,14 +30,17 @@ module Compilers
       #   `without_defaults_*` methods
       class RuboCop < Compiler
         ConstantType = type_member do
-          { fixed: T.all(T.class_of(::RuboCop::AST::NodePattern::Macros), Extensions::RuboCop) }
+          { fixed: T.all(Module, Extensions::RuboCop) }
         end
 
         class << self
           extend T::Sig
-          sig { override.returns(T::Enumerable[T.class_of(::RuboCop::AST::NodePattern::Macros)]) }
+          sig { override.returns(T::Array[T.all(Module, Extensions::RuboCop)]) }
           def gather_constants
-            descendants_of(::RuboCop::AST::NodePattern::Macros).select { |constant| name_of(constant) }
+            T.cast(
+              extenders_of(::RuboCop::AST::NodePattern::Macros).select { |constant| name_of(constant) },
+              T::Array[T.all(Module, Extensions::RuboCop)],
+            )
           end
         end
 

lib/tapioca/dsl/extensions/rubocop.rb

@@ -1,7 +1,7 @@
 # typed: strict
 # frozen_string_literal: true
 
-return unless defined?(RuboCop)
+return unless defined?(RuboCop::AST::NodePattern::Macros)
 
 module Tapioca
   module Dsl

lib/tapioca/runtime/reflection.rb

@@ -146,7 +146,7 @@ def method_of(constant, method)
         METHOD_METHOD.bind_call(constant, method)
       end
 
-      # Returns an array with all modules that are < than the supplied module.
+      # Returns an array with all classes that are < than the supplied class.
       #
       #   class C; end
       #   descendants_of(C) # => []
@@ -159,26 +159,30 @@ def method_of(constant, method)
       #
       #   class D < C; end
       #   descendants_of(C) # => [B, A, D]
-      #
-      #   module M; end
-      #   class E
-      #     include M
-      #   end
-      #   descendants_of(M) # => [E]
       sig do
         type_parameters(:U)
-          .params(mod: T.all(Module, T.type_parameter(:U)))
+          .params(klass: T.all(T::Class[T.anything], T.type_parameter(:U)))
           .returns(T::Array[T.type_parameter(:U)])
       end
-      def descendants_of(mod)
-        result = ObjectSpace
-          .each_object(Module)
-          .select { |m| T.cast(m, Module) < mod }
-          .reject { |m| T.cast(m, Module).singleton_class? || T.unsafe(m) == mod }
+      def descendants_of(klass)
+        result = ObjectSpace.each_object(klass.singleton_class).reject do |k|
+          T.cast(k, Module).singleton_class? || T.unsafe(k) == klass
+        end
 
         T.unsafe(result)
       end
 
+      # Returns an array with all modules which extend the supplied module
+      # (i.e. all modules whose singleton class, or ancestor thereof, includes the supplied module).
+      sig { params(mod: Module).returns(T::Array[Module]) }
+      def extenders_of(mod)
+        result = ObjectSpace.each_object(Module).select do |m|
+          T.cast(m, Module).singleton_class.included_modules.include?(mod)
+        end
+
+        T.cast(result, T::Array[Module])
+      end
+
       # Examines the call stack to identify the closest location where a "require" is performed
       # by searching for the label "<top (required)>". If none is found, it returns the location
       # labeled "<main>", which is the original call site.

spec/tapioca/dsl/compilers/rubocop_spec.rb

@@ -2,20 +2,20 @@
 # frozen_string_literal: true
 
 require "spec_helper"
-require "rubocop"
-require "rubocop-sorbet"
+# require "rubocop"
+# require "rubocop-sorbet"
 
 module Tapioca
   module Dsl
     module Compilers
       class RuboCopSpec < ::DslSpec
-        # Collect constants from gems, before defining any in tests.
-        EXISTING_CONSTANTS = T.let(
-          Runtime::Reflection
-            .descendants_of(::RuboCop::Cop::Base)
-            .filter_map { |constant| Runtime::Reflection.name_of(constant) },
-          T::Array[String],
-        )
+        # # Collect constants from gems, before defining any in tests.
+        # EXISTING_CONSTANTS = T.let(
+        #   Runtime::Reflection
+        #     .extenders_of(::RuboCop::AST::NodePattern::Macros)
+        #     .filter_map { |constant| Runtime::Reflection.name_of(constant) },
+        #   T::Array[String],
+        # )
 
         class << self
           extend T::Sig
@@ -30,20 +30,24 @@ def target_class_file
         describe "Tapioca::Dsl::Compilers::RuboCop" do
           sig { void }
           def before_setup
+            require "rubocop"
+            require "rubocop-sorbet"
             require "tapioca/dsl/extensions/rubocop"
             super
           end
 
           describe "initialize" do
             it "gathered constants exclude irrelevant classes" do
-              add_ruby_file("content.rb", <<~RUBY)
-                class Unrelated
-                end
-              RUBY
-              assert_empty(relevant_gathered_constants)
+              gathered_constants = gather_constants do
+                add_ruby_file("content.rb", <<~RUBY)
+                  class Unrelated
+                  end
+                RUBY
+              end
+              assert_empty(gathered_constants)
             end
 
-            it "gathers constants inheriting RuboCop::Cop::Base in gems" do
+            it "gathers constants extending RuboCop::AST::NodePattern::Macros in gems" do
               # Sample of miscellaneous constants that should be found from Rubocop and plugins
               missing_constants = [
                 "RuboCop::Cop::Bundler::GemVersion",
@@ -61,27 +65,33 @@ class Unrelated
               assert_empty(missing_constants, "expected constants to be gathered")
             end
 
-            it "gathers constants inheriting from RuboCop::Cop::Base in the host app" do
-              add_ruby_file("content.rb", <<~RUBY)
-                class MyCop < ::RuboCop::Cop::Base
-                end
+            it "gathers constants extending RuboCop::AST::NodePattern::Macros in the host app" do
+              gathered_constants = gather_constants do
+                add_ruby_file("content.rb", <<~RUBY)
+                  class MyCop < ::RuboCop::Cop::Base
+                  end
 
-                class MyLegacyCop < ::RuboCop::Cop::Cop
-                end
+                  class MyLegacyCop < ::RuboCop::Cop::Cop
+                  end
 
-                module ::RuboCop
-                  module Cop
-                    module MyApp
-                      class MyNamespacedCop < Base
+                  module MyMacroModule
+                    extend ::RuboCop::AST::NodePattern::Macros
+                  end
+
+                  module ::RuboCop
+                    module Cop
+                      module MyApp
+                        class MyNamespacedCop < Base
+                        end
                       end
                     end
                   end
-                end
-              RUBY
+                RUBY
+              end
 
               assert_equal(
-                ["MyCop", "MyLegacyCop", "RuboCop::Cop::MyApp::MyNamespacedCop"],
-                relevant_gathered_constants,
+                ["MyCop", "MyLegacyCop", "MyMacroModule", "RuboCop::Cop::MyApp::MyNamespacedCop"],
+                gathered_constants,
               )
             end
           end
@@ -155,9 +165,17 @@ def without_defaults_some_search_with_params_and_defaults(param0, param1, two:);
 
           private
 
-          sig { returns(T::Array[String]) }
-          def relevant_gathered_constants
-            gathered_constants - EXISTING_CONSTANTS
+          # Gathers constants introduced in the given block excluding constants that already existed prior to the block.
+          sig { params(block: T.proc.void).returns(T::Array[String]) }
+          def gather_constants(&block)
+            existing_constants = T.let(
+              Runtime::Reflection
+                .extenders_of(::RuboCop::AST::NodePattern::Macros)
+                .filter_map { |constant| Runtime::Reflection.name_of(constant) },
+              T::Array[String],
+            )
+            yield
+            gathered_constants - existing_constants
           end
         end
       end