import tester.*;

/**
 * Test cases for Posn rewritten using Viera's tester library.
 * 
 * @author Stephen Bloch
 * @version 9 (Feb. 10, 2009)
 */
public class Examples
{
    Posn origin = new Posn(0.,0.);
    Posn p1 = new Posn(0.,3.);
    Posn p2 = new Posn(-4.2,0.);
    Posn p2flipped = new Posn(4.2,0.);
    Posn p3 = new Posn(3.,-4.);
    Posn p4 = new Posn(-7.1, -9.7);

    public static void testEverything()
    {
        Tester.run (new Examples());
	// Automatically runs all non-static methods in Examples whose names
	// start with  "test", e.g. testBasics, testDistanceToOrigin,
	// testSwapCoords, etc.
    }
    
    /**
     * testBasics: make sure constructor and fields work.
     * 
     * @param   t   the Tester to use
     * No return value; either succeeds or fails.
     */
    public void testBasics (Tester t)
    {
        t.checkExpect(origin.x, 0.);
        t.checkExpect(origin.y, 0.);
        t.checkExpect(p1.x, 0.);
        t.checkExpect(p1.y, 3.);
        t.checkExpect(p3.x, 3.);
        t.checkExpect(p3.y, -4.);
    }
    
    /**
     * testDistanceToOrigin: make sure distance to (0,0) works.
     * 
     * @param   t   the Tester to use
     * No return value; either succeeds or fails.
     */
    public void testDistanceToOrigin (Tester t)
    {
        t.checkExpect(origin.distanceToOrigin(), 0.);
        t.checkExpect(p1.distanceToOrigin(), 3.);
        t.checkExpect(p2.distanceToOrigin(), 4.2);
        t.checkExpect(p2flipped.distanceToOrigin(), 4.2);
        t.checkExpect(p3.distanceToOrigin(), 5.);
        t.setTolerance (0.1);
        t.checkExpect(p4.distanceToOrigin(), 12.);
        // fails if you ask for exact equality
    }
 
    /**
     * testCoordDifference: similar; fill it in for yourself.
     */
    
    /**
     * testToString: make sure toString works.
     * 
     * @param   t   the Tester to use
     * No return value; either succeeds or fails.
     */
    public void testToString (Tester t)
    {
        t.checkExpect(origin.toString(), "Posn(0.0, 0.0)");
        t.checkExpect(p1.toString(), "Posn(0.0, 3.0)");
        t.checkExpect(p2.toString(), "Posn(-4.2, 0.0)");
        t.checkExpect(p3.toString(), "Posn(3.0, -4.0)");
        t.checkExpect(p4.toString(), "Posn(-7.1, -9.7)");
    }

    /**
     * testSwapCoords: make sure swapCoords works.
     * 
     * @param   t   the Tester to use
     * No return value; either succeeds or fails.
     * 
     * Note: since swapCoords returns a Posn, it's MUCH easier to
     * test using the tester library than using JUnit.
     */
    public void testSwapCoords (Tester t)
    {
        t.checkExpect (origin.swapCoords(), origin);
        t.checkExpect (p1.swapCoords(), new Posn(3., 0.));
        t.checkExpect (p2.swapCoords(), new Posn(0., -4.2));
        t.checkExpect (p3.swapCoords(), new Posn(-4., 3.));
        t.checkExpect (p4.swapCoords(), new Posn(-9.7, -7.1));
        t.checkExpect (p4.swapCoords(), p3); // should fail
    }
}