Merge pull request #229 from fatkodima/hidden_test_method-cop

Add new `Minitest/NonPublicTestMethod` cop

changelog/new_non_public_test_method_cop.md

@@ -0,0 +1 @@
+* [#220](https://github.com/rubocop/rubocop-minitest/issues/220): Add new `Minitest/NonPublicTestMethod` cop. ([@fatkodima][])

config/default.yml

@@ -175,6 +175,12 @@ Minitest/NoAssertions:
   Enabled: false
   VersionAdded: '0.12'
 
+Minitest/NonPublicTestMethod:
+  Description: 'Detects non `public` (marked as `private` or `protected`) test methods.'
+  Enabled: pending
+  Severity: warning
+  VersionAdded: '<<next>>'
+
 Minitest/RefuteEmpty:
   Description: 'This cop enforces to use `refute_empty` instead of using `refute(object.empty?)`.'
   StyleGuide: 'https://minitest.rubystyle.guide#refute-empty'

lib/rubocop/cop/minitest/non_public_test_method.rb

@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+module RuboCop
+  module Cop
+    module Minitest
+      # Detects non `public` (marked as `private` or `protected`) test methods.
+      # Minitest runs only test methods which are `public`.
+      #
+      # @example
+      #   # bad
+      #   class FooTest
+      #     private # or protected
+      #     def test_does_something
+      #       assert_equal 42, do_something
+      #     end
+      #   end
+      #
+      #   # good
+      #   class FooTest
+      #     def test_does_something
+      #       assert_equal 42, do_something
+      #     end
+      #   end
+      #
+      #   # good (not a test case name)
+      #   class FooTest
+      #     private # or protected
+      #     def does_something
+      #       assert_equal 42, do_something
+      #     end
+      #   end
+      #
+      #   # good (no assertions)
+      #   class FooTest
+      #     private # or protected
+      #     def test_does_something
+      #       do_something
+      #     end
+      #   end
+      #
+      class NonPublicTestMethod < Base
+        include MinitestExplorationHelpers
+        include DefNode
+
+        MSG = 'Non `public` test method detected. Make it `public` for it to run.'
+
+        def on_class(node)
+          test_cases(node).each do |test_case|
+            add_offense(test_case) if non_public?(test_case) && assertions(test_case).any?
+          end
+        end
+      end
+    end
+  end
+end

lib/rubocop/cop/minitest_cops.rb

@@ -33,6 +33,7 @@
 require_relative 'minitest/literal_as_actual_argument'
 require_relative 'minitest/multiple_assertions'
 require_relative 'minitest/no_assertions'
+require_relative 'minitest/non_public_test_method'
 require_relative 'minitest/refute_empty'
 require_relative 'minitest/refute_false'
 require_relative 'minitest/refute_equal'

test/rubocop/cop/minitest/non_public_test_method_test.rb

@@ -0,0 +1,75 @@
+# frozen_string_literal: true
+
+require 'test_helper'
+
+class NonPublicTestMethodTest < Minitest::Test
+  def test_registers_offense_when_using_private_test_method
+    assert_offense(<<~RUBY)
+      class FooTest < Minitest::Test
+        private
+        def test_does_something
+        ^^^^^^^^^^^^^^^^^^^^^^^ Non `public` test method detected. Make it `public` for it to run.
+          assert_equal 42, do_something
+        end
+      end
+    RUBY
+  end
+
+  def test_registers_offense_when_using_protected_test_method
+    assert_offense(<<~RUBY)
+      class FooTest < Minitest::Test
+        protected
+        def test_does_something
+        ^^^^^^^^^^^^^^^^^^^^^^^ Non `public` test method detected. Make it `public` for it to run.
+          assert_equal 42, do_something
+        end
+      end
+    RUBY
+  end
+
+  def test_registers_offense_when_using_private_test_method_outside_of_test_class
+    assert_offense(<<~RUBY)
+      class FooTest
+        private
+        def test_does_something
+        ^^^^^^^^^^^^^^^^^^^^^^^ Non `public` test method detected. Make it `public` for it to run.
+          assert_equal 42, do_something
+        end
+      end
+    RUBY
+  end
+
+  def test_registers_offense_when_using_private_active_support_test_method
+    assert_offense(<<~RUBY)
+      class FooTest
+        private
+        test "does something"  do
+        ^^^^^^^^^^^^^^^^^^^^^^^^^ Non `public` test method detected. Make it `public` for it to run.
+          assert_equal 42, do_something
+        end
+      end
+    RUBY
+  end
+
+  def test_does_not_register_offense_when_using_private_non_test_method_with_assertions
+    assert_no_offenses(<<~RUBY)
+      class FooTest < Minitest::Test
+        private
+        def does_something
+          assert_equal 42, do_something
+        end
+      end
+    RUBY
+  end
+
+  def test_does_not_register_offense_when_using_private_test_method_without_assertions
+    assert_no_offenses(<<~RUBY)
+      class FooTest < Minitest::Test
+        private
+        def test_does_something
+          do_something
+        end
+      end
+    RUBY
+  end
+end