Should it be “Arrange-Assert-Act-Assert”?

Question

Regarding the classic test pattern of Arrange-Act-Assert, I frequently find myself adding a counter-assertion that precedes Act. This way I know that the passing assertion

Answer 1

I don't use that pattern, because I think doing something like:

Arrange
Assert-Not
Act
Assert

May be pointless, because supposedly you know your Arrange part works correctly, which means that whatever is in the Arrange part must be tested aswell or be simple enough to not need tests.

Using your answer's example:

public void testEncompass() throws Exception {
    Range range = new Range(0, 5);
    assertFalse(range.includes(7)); // <-- Pointless and against DRY if there 
                                    // are unit tests for Range(int, int)
    range.encompass(7);
    assertTrue(range.includes(7));
}