| `assert( test, [msg] )` | Ensures that `test` is true.|
| `refute( test, [msg] )` | Ensures that `test` is false.|
| `assert_not( test, [msg] )` | Ensures that `test` is false.|
| `assert_equal( expected, actual, [msg] )` | Ensures that `expected == actual` is true.|
| `refute_equal( expected, actual, [msg] )` | Ensures that `expected != actual` is true.|
| `assert_not_equal( expected, actual, [msg] )` | Ensures that `expected != actual` is true.|
| `assert_same( expected, actual, [msg] )` | Ensures that `expected.equal?(actual)` is true.|
| `refute_same( expected, actual, [msg] )` | Ensures that `expected.equal?(actual)` is false.|
| `assert_not_same( expected, actual, [msg] )` | Ensures that `expected.equal?(actual)` is false.|
| `assert_nil( obj, [msg] )` | Ensures that `obj.nil?` is true.|
| `refute_nil( obj, [msg] )` | Ensures that `obj.nil?` is false.|
| `assert_not_nil( obj, [msg] )` | Ensures that `obj.nil?` is false.|
| `assert_match( regexp, string, [msg] )` | Ensures that a string matches the regular expression.|
| `refute_match( regexp, string, [msg] )` | Ensures that a string doesn't match the regular expression.|
| `assert_no_match( regexp, string, [msg] )` | Ensures that a string doesn't match the regular expression.|
| `assert_in_delta( expecting, actual, [delta], [msg] )` | Ensures that the numbers `expected` and `actual` are within `delta` of each other.|
| `refute_in_delta( expecting, actual, [delta], [msg] )` | Ensures that the numbers `expected` and `actual` are not within `delta` of each other.|
| `assert_not_in_delta( expecting, actual, [delta], [msg] )` | Ensures that the numbers `expected` and `actual` are not within `delta` of each other.|
| `assert_throws( symbol, [msg] ) { block }` | Ensures that the given block throws the symbol.|
| `assert_raises( exception1, exception2, ... ) { block }` | Ensures that the given block raises one of the given exceptions.|
| `assert_nothing_raised( exception1, exception2, ... ) { block }` | Ensures that the given block doesn't raise one of the given exceptions.|
| `assert_instance_of( class, obj, [msg] )` | Ensures that `obj` is an instance of `class`.|
| `refute_instance_of( class, obj, [msg] )` | Ensures that `obj` is not an instance of `class`.|
| `assert_not_instance_of( class, obj, [msg] )` | Ensures that `obj` is not an instance of `class`.|
| `assert_kind_of( class, obj, [msg] )` | Ensures that `obj` is or descends from `class`.|
| `refute_kind_of( class, obj, [msg] )` | Ensures that `obj` is not an instance of `class` and is not descending from it.|
| `assert_not_kind_of( class, obj, [msg] )` | Ensures that `obj` is not an instance of `class` and is not descending from it.|
| `assert_respond_to( obj, symbol, [msg] )` | Ensures that `obj` responds to `symbol`.|
| `refute_respond_to( obj, symbol, [msg] )` | Ensures that `obj` does not respond to `symbol`.|
| `assert_not_respond_to( obj, symbol, [msg] )` | Ensures that `obj` does not respond to `symbol`.|
| `assert_operator( obj1, operator, [obj2], [msg] )` | Ensures that `obj1.operator(obj2)` is true.|
| `refute_operator( obj1, operator, [obj2], [msg] )` | Ensures that `obj1.operator(obj2)` is false.|
| `assert_not_operator( obj1, operator, [obj2], [msg] )` | Ensures that `obj1.operator(obj2)` is false.|
| `assert_send( array, [msg] )` | Ensures that executing the method listed in `array[1]` on the object in `array[0]` with the parameters of `array[2 and up]` is true. This one is weird eh?|
| `flunk( [msg] )` | Ensures failure. This is useful to explicitly mark a test that isn't finished yet.|