3 files changed, 155 insertions, 0 deletions
diff --git a/ci/custom_cops/test/custom_cops/assert_not_test.rb b/ci/custom_cops/test/custom_cops/assert_not_test.rb
new file mode 100644
index 0000000000..abb151aeb4
--- /dev/null
+++ b/ci/custom_cops/test/custom_cops/assert_not_test.rb
@@ -0,0 +1,42 @@
+# frozen_string_literal: true
+
+require "support/cop_helper"
+require_relative "../../lib/custom_cops/assert_not"
+
+class AssertNotTest < ActiveSupport::TestCase
+  include CopHelper
+
+  setup do
+    @cop = CustomCops::AssertNot.new
+  end
+
+  test "rejects 'assert !'" do
+    inspect_source @cop, "assert !x"
+    assert_offense @cop, "^^^^^^^^^ Prefer `assert_not` over `assert !`"
+  end
+
+  test "rejects 'assert !' with a complex value" do
+    inspect_source @cop, "assert !a.b(c)"
+    assert_offense @cop, "^^^^^^^^^^^^^^ Prefer `assert_not` over `assert !`"
+  end
+
+  test "autocorrects `assert !`" do
+    corrected = autocorrect_source(@cop, "assert !false")
+    assert_equal "assert_not false", corrected
+  end
+
+  test "autocorrects `assert !` with extra spaces" do
+    corrected = autocorrect_source(@cop, "assert   !  false")
+    assert_equal "assert_not false", corrected
+  end
+
+  test "autocorrects `assert !` with parentheses" do
+    corrected = autocorrect_source(@cop, "assert(!false)")
+    assert_equal "assert_not(false)", corrected
+  end
+
+  test "accepts `assert_not`" do
+    inspect_source @cop, "assert_not x"
+    assert_empty @cop.offenses
+  end
+end
diff --git a/ci/custom_cops/test/custom_cops/refute_not_test.rb b/ci/custom_cops/test/custom_cops/refute_not_test.rb
new file mode 100644
index 0000000000..f0f6eaeda0
--- /dev/null
+++ b/ci/custom_cops/test/custom_cops/refute_not_test.rb
@@ -0,0 +1,66 @@
+# frozen_string_literal: true
+
+require "support/cop_helper"
+require_relative "../../lib/custom_cops/refute_not"
+
+class RefuteNotTest < ActiveSupport::TestCase
+  include CopHelper
+
+  setup do
+    @cop = CustomCops::RefuteNot.new
+  end
+
+  {
+    refute:             :assert_not,
+    refute_empty:       :assert_not_empty,
+    refute_equal:       :assert_not_equal,
+    refute_in_delta:    :assert_not_in_delta,
+    refute_in_epsilon:  :assert_not_in_epsilon,
+    refute_includes:    :assert_not_includes,
+    refute_instance_of: :assert_not_instance_of,
+    refute_kind_of:     :assert_not_kind_of,
+    refute_nil:         :assert_not_nil,
+    refute_operator:    :assert_not_operator,
+    refute_predicate:   :assert_not_predicate,
+    refute_respond_to:  :assert_not_respond_to,
+    refute_same:        :assert_not_same,
+    refute_match:       :assert_no_match
+  }.each do |refute_method, assert_method|
+    test "rejects `#{refute_method}` with a single argument" do
+      inspect_source(@cop, "#{refute_method} a")
+      assert_offense @cop, offense_message(refute_method, assert_method)
+    end
+
+    test "rejects `#{refute_method}` with multiple arguments" do
+      inspect_source(@cop, "#{refute_method} a, b, c")
+      assert_offense @cop, offense_message(refute_method, assert_method)
+    end
+
+    test "autocorrects `#{refute_method}` with a single argument" do
+      corrected = autocorrect_source(@cop, "#{refute_method} a")
+      assert_equal "#{assert_method} a", corrected
+    end
+
+    test "autocorrects `#{refute_method}` with multiple arguments" do
+      corrected = autocorrect_source(@cop, "#{refute_method} a, b, c")
+      assert_equal "#{assert_method} a, b, c", corrected
+    end
+
+    test "accepts `#{assert_method}` with a single argument" do
+      inspect_source(@cop, "#{assert_method} a")
+      assert_empty @cop.offenses
+    end
+
+    test "accepts `#{assert_method}` with multiple arguments" do
+      inspect_source(@cop, "#{assert_method} a, b, c")
+      assert_empty @cop.offenses
+    end
+  end
+
+  private
+
+    def offense_message(refute_method, assert_method)
+      carets = "^" * refute_method.to_s.length
+      "#{carets} Prefer `#{assert_method}` over `#{refute_method}`"
+    end
+end
diff --git a/ci/custom_cops/test/support/cop_helper.rb b/ci/custom_cops/test/support/cop_helper.rb
new file mode 100644
index 0000000000..c2c6b969dd
--- /dev/null
+++ b/ci/custom_cops/test/support/cop_helper.rb
@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+require "rubocop"
+
+module CopHelper
+  def inspect_source(cop, source)
+    processed_source = parse_source(source)
+    raise "Error parsing example code" unless processed_source.valid_syntax?
+    investigate(cop, processed_source)
+    processed_source
+  end
+
+  def autocorrect_source(cop, source)
+    cop.instance_variable_get(:@options)[:auto_correct] = true
+    processed_source = inspect_source(cop, source)
+    rewrite(cop, processed_source)
+  end
+
+  def assert_offense(cop, expected_message)
+    assert_not_empty(
+      cop.offenses,
+      "Expected offense with message \"#{expected_message}\", but got no offense"
+    )
+
+    offense = cop.offenses.first
+    carets = "^" * offense.column_length
+
+    assert_equal expected_message, "#{carets} #{offense.message}"
+  end
+
+  private
+    TARGET_RUBY_VERSION = 2.4
+
+    def parse_source(source)
+      RuboCop::ProcessedSource.new(source, TARGET_RUBY_VERSION)
+    end
+
+    def rewrite(cop, processed_source)
+      RuboCop::Cop::Corrector.new(processed_source.buffer, cop.corrections)
+        .rewrite
+    end
+
+    def investigate(cop, processed_source)
+      RuboCop::Cop::Commissioner.new([cop], [], raise_error: true)
+        .investigate(processed_source)
+    end
+end