Fix a false positive for Minitest/EmptyLineBeforeAssertionMethods and assert_raises

changelog/fix_false_positive_for_empty_line_before_assertion_methods_and_assert_raises.md

@@ -0,0 +1 @@
+* [#271](https://github.com/rubocop/rubocop-minitest/issues/271): Fix a false positive for `Minitest/EmptyLineBeforeAssertionMethods` and `assert_raises`. ([@fatkodima][])

lib/rubocop/cop/mixin/minitest_exploration_helpers.rb

@@ -100,6 +100,7 @@ def assertions_count(node)
       end
 
       def assertion_method?(node)
+        return assertion_method?(node.expression) if node.assignment?
         return false if !node.send_type? && !node.block_type? && !node.numblock_type?
 
         ASSERTION_PREFIXES.any? do |prefix|

test/rubocop/cop/minitest/empty_line_before_assertion_methods_test.rb

@@ -110,18 +110,30 @@ def test_do_something
   def test_registers_offense_when_using_method_call_with_block_arg_before_assertion_method
     assert_offense(<<~RUBY)
       def test_do_something
-        block = -> { raise CustomError, 'This is really bad' }
-        error = assert_raises(CustomError, &block)
-        assert_equal 'This is really bad', error.message
-        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Add empty line before assertion.
+        do_something do
+          do_something_more
+        end
+        assert_equal(expected, actual)
+        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Add empty line before assertion.
       end
     RUBY
 
     assert_correction(<<~RUBY)
+      def test_do_something
+        do_something do
+          do_something_more
+        end
+
+        assert_equal(expected, actual)
+      end
+    RUBY
+  end
+
+  def test_does_not_register_offense_when_using_assertion_method_with_assignment_before_assertion_method
+    assert_no_offenses(<<~RUBY)
       def test_do_something
         block = -> { raise CustomError, 'This is really bad' }
         error = assert_raises(CustomError, &block)
-
         assert_equal 'This is really bad', error.message
       end
     RUBY