feat(gem): add option to omit private methods

README.md

@@ -188,6 +188,9 @@ Options:
                                                                                                      # Default: false
   --typed, -t, [--typed-overrides=gem:level [gem:level ...]]                                         # Override for typed sigils for generated gem RBIs
                                                                                                      # Default: {"activesupport" => "false"}
+               [--private-methods], [--no-private-methods], [--skip-private-methods]                 # Include private methods in generated gem RBIs
+                                                                                                     # Default: true
+               [--private-methods-for=gem [gem ...]]                                                 # Always include private methods for the given gems
                [--verify], [--no-verify], [--skip-verify]                                            # Verify RBIs are up-to-date
                                                                                                      # Default: false
                [--doc], [--no-doc], [--skip-doc]                                                     # Include documentation from sources when generating RBIs
@@ -1014,6 +1017,16 @@ gem:
   doc: true
 ```
 
+Private methods are included by default. To omit them and keep them only for selected gems, configure `private_methods` and `private_methods_for`:
+
+```yaml
+gem:
+  private_methods: false
+  private_methods_for:
+  - rake
+  - activerecord
+```
+
 Additionally, if you always want to exclude the `AASM` and `ActiveRecordFixtures` DSL compilers in your DSL RBI generation runs, your config file would then look like this:
 
 ```yaml
@@ -1060,6 +1073,8 @@ gem:
   include_dependencies: false
   typed_overrides:
     activesupport: 'false'
+  private_methods: true
+  private_methods_for: []
   verify: false
   doc: true
   loc: true

lib/tapioca/cli.rb

@@ -228,6 +228,15 @@ def dsl(*constant_or_paths)
       banner: "gem:level [gem:level ...]",
       desc: "Override for typed sigils for generated gem RBIs",
       default: DEFAULT_OVERRIDES
+    option :private_methods,
+      type: :boolean,
+      desc: "Include private methods in generated gem RBIs",
+      default: true
+    option :private_methods_for,
+      type: :array,
+      banner: "gem [gem ...]",
+      desc: "Always include private methods for the given gems",
+      default: []
     option :verify,
       type: :boolean,
       desc: "Verify RBIs are up-to-date",
@@ -299,6 +308,8 @@ def gem(*gems)
         prerequire: options[:prerequire],
         postrequire: options[:postrequire],
         typed_overrides: options[:typed_overrides],
+        private_methods: options[:private_methods],
+        private_methods_for: options[:private_methods_for],
         outpath: Pathname.new(options[:outdir]),
         file_header: options[:file_header],
         include_doc: options[:doc],

lib/tapioca/commands/abstract_gem.rb

@@ -15,6 +15,8 @@ class AbstractGem < Command
       #|   prerequire: String?,
       #|   postrequire: String,
       #|   typed_overrides: Hash[String, String],
+      #|   private_methods: bool,
+      #|   private_methods_for: Array[String],
       #|   outpath: Pathname,
       #|   file_header: bool,
       #|   include_doc: bool,
@@ -35,6 +37,8 @@ def initialize(
         prerequire:,
         postrequire:,
         typed_overrides:,
+        private_methods:,
+        private_methods_for:,
         outpath:,
         file_header:,
         include_doc:,
@@ -54,6 +58,8 @@ def initialize(
         @prerequire = prerequire
         @postrequire = postrequire
         @typed_overrides = typed_overrides
+        @private_methods = private_methods
+        @private_methods_for = private_methods_for
         @outpath = outpath
         @file_header = file_header
         @number_of_workers = number_of_workers
@@ -102,6 +108,7 @@ def compile_gem_rbi(gem)
         end
 
         merge_with_exported_rbi(gem, rbi) if @include_exported_rbis
+        remove_private_methods(rbi.root) if omit_private_methods?(gem)
 
         if rbi.empty?
           @rbi_formatter.write_empty_body_comment!(rbi)
@@ -288,6 +295,22 @@ def merge_with_exported_rbi(gem, file)
         say_error("\n\n  RBIs exported by `#{gem.name}` contain errors and can't be used:", :yellow)
         say_error("Cause: #{e.message} (#{e.location})")
       end
+
+      #: (Gemfile::GemSpec gem) -> bool
+      def omit_private_methods?(gem)
+        !@private_methods && !@private_methods_for.include?(gem.name)
+      end
+
+      #: (RBI::Tree tree) -> void
+      def remove_private_methods(tree)
+        tree.nodes.dup.each do |node|
+          if node.is_a?(RBI::Tree)
+            remove_private_methods(node)
+          elsif (node.is_a?(RBI::Method) || node.is_a?(RBI::Attr)) && node.visibility.private?
+            node.detach
+          end
+        end
+      end
     end
   end
 end

lib/tapioca/commands/configure.rb

@@ -52,6 +52,9 @@ def create_tapioca_config
             # - gem_name
             # doc: true
             # workers: 5
+            # private_methods: false
+            # private_methods_for:
+            # - gem_name
           dsl:
             # Add your `dsl` command parameters here:
             #

spec/tapioca/cli/config_spec.rb

@@ -72,9 +72,11 @@ class ConfigTest < SpecWithProject
         @project.write!("sorbet/tapioca/config.yml", <<~YAML)
           gem:
             doc: "true"
+            private_methods: "false"
             typed_overrides:
             - "true"
             - "false"
+            private_methods_for: [1, false]
             workers: "foo"
           dsl:
             exclude: true
@@ -87,7 +89,9 @@ class ConfigTest < SpecWithProject
           Configuration file sorbet/tapioca/config.yml has the following errors:
 
           - invalid value for option doc for key gem - expected Boolean but found String
+          - invalid value for option private_methods for key gem - expected Boolean but found String
           - invalid value for option typed_overrides for key gem - expected Hash but found Array
+          - invalid value for option private_methods_for for key gem - expected Array[String] but found [1, false]
           - invalid value for option workers for key gem - expected Numeric but found String
           - invalid value for option exclude for key dsl - expected Array but found Boolean
         ERR

spec/tapioca/cli/gem_spec.rb

@@ -381,6 +381,130 @@ module Reopened; end
           assert_success_status(result)
         end
 
+        it "must filter every private method from the complete gem RBI when configured" do
+          foo = mock_gem("foo", "0.0.1") do
+            write!("lib/foo.rb", <<~RB)
+              module Foo
+                def public_method; end
+
+                private
+
+                def private_a; end
+                def private_b; end
+                def private_c; end
+                def private_d; end
+
+                class << self
+                  def public_class_method; end
+
+                  private
+
+                  def private_class_a; end
+                  def private_class_b; end
+                end
+              end
+            RB
+
+            write!("rbi/foo.rbi", <<~RBI)
+              module Foo
+                def exported_method; end
+
+                private def exported_private_a; end
+                private def exported_private_b; end
+
+                class << self
+                  def exported_class_method; end
+
+                  private def exported_private_class_a; end
+                  private def exported_private_class_b; end
+                end
+              end
+            RBI
+          end
+
+          @project.require_mock_gem(foo)
+          @project.bundle_install!
+
+          expected_with_private_methods = <<~RBI
+            # typed: true
+
+            # DO NOT EDIT MANUALLY
+            # This is an autogenerated file for types exported from the `foo` gem.
+            # Please instead update this file by running `bin/tapioca gem foo`.
+
+
+            module Foo
+              def exported_method; end
+              def public_method; end
+
+              private
+
+              def exported_private_a; end
+              def exported_private_b; end
+              def private_a; end
+              def private_b; end
+              def private_c; end
+              def private_d; end
+
+              class << self
+                def exported_class_method; end
+                def public_class_method; end
+
+                private
+
+                def exported_private_class_a; end
+                def exported_private_class_b; end
+                def private_class_a; end
+                def private_class_b; end
+              end
+            end
+          RBI
+
+          result = @project.tapioca("gem foo")
+
+          assert_success_status(result)
+          assert_project_file_equal("sorbet/rbi/gems/foo@0.0.1.rbi", expected_with_private_methods)
+
+          @project.write!("sorbet/tapioca/config.yml", <<~YAML)
+            gem:
+              private_methods: false
+          YAML
+
+          result = @project.tapioca("gem foo")
+
+          assert_success_status(result)
+          assert_project_file_equal("sorbet/rbi/gems/foo@0.0.1.rbi", <<~RBI)
+            # typed: true
+
+            # DO NOT EDIT MANUALLY
+            # This is an autogenerated file for types exported from the `foo` gem.
+            # Please instead update this file by running `bin/tapioca gem foo`.
+
+
+            module Foo
+              def exported_method; end
+              def public_method; end
+
+              class << self
+                def exported_class_method; end
+                def public_class_method; end
+              end
+            end
+          RBI
+
+          @project.write!("sorbet/tapioca/config.yml", <<~YAML)
+            gem:
+              private_methods: false
+              private_methods_for:
+              - foo
+          YAML
+
+          result = @project.tapioca("gem foo")
+
+          assert_success_status(result)
+          assert_project_file_equal("sorbet/rbi/gems/foo@0.0.1.rbi", expected_with_private_methods)
+        end
+
         it "must output currently compiling status with verbose flag" do
           foo = mock_gem("foo", "0.0.1") do
             write!("lib/foo.rb", FOO_RB)