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Koans/src/test/scala/org/functionalkoans/forscala/Flight03.scala

@@ -4,7 +4,7 @@ import support.BlankValues._
 import support.KoanSuite
 
 class Flight03 extends KoanSuite with ShouldMatchers {
-
+ 
  // Flight 03 exercise - uncomment the tests below, and then define a class
  // called ComplexNum that:
  // 1. Has class parameters real and imaginary
@@ -21,10 +21,25 @@ class Flight03 extends KoanSuite with ShouldMatchers {
  // The tests below should exercise all of these requirements although they
  // are far from exhaustive
 
- // class ...
+ class ComplexNum( val real: Double, val imaginary: Double ) {
+ def this( real: Double ) { this( real, 0d) }
+
+ override def toString = this.imaginary match {
+ case x: Double if(x < 0) => real + " - " + math.abs(imaginary) + "i" 
+ case x: Double => real + " + " + imaginary + "i" 
+ }
+
+ def +( other: ComplexNum ) : ComplexNum = { 
+ new ComplexNum( this.real + other.real, this.imaginary + other.imaginary )
+ }
+
+ def +( num: Double ) = new ComplexNum( this.real + num, this.imaginary )
+ }
+
+ implicit def double2ComplexNum( double: Double ) = new ComplexNum( double )
 
  // UNCOMMENT BELOW
- /*test ("Create a new Complex number and check the values for the real/imaginary parts") {
+ test ("Create a new Complex number and check the values for the real/imaginary parts") {
  val complex = new ComplexNum(4, 2)
 
  complex.real should be (4)
@@ -67,32 +82,31 @@ class Flight03 extends KoanSuite with ShouldMatchers {
 
  complex.real should be (12)
  complex.imaginary should be (3.2)
- }
- */
+ } 
  // Extra credit - numbers with a negative imaginary part should be output
  // as 6.0 - 5.0i instead of 6.0 + -5.0i - if you have time, write a new test
  // for this outcome, and then adapt the toString in the class to work correctly
  // Hint: scala.math.abs will give the absolute value of a double
-
+ 
  // UNCOMMENT BELOW
- /*test ("Format for negative imaginary part should be R.R - I.Ii") {
+ test ("Format for negative imaginary part should be R.R - I.Ii") {
  val complex = new ComplexNum(5, -6)
  val complex2 = new ComplexNum(5.5, -6.6)
 
  complex.toString should be ("5.0 - 6.0i")
  complex2.toString should be ("5.5 - 6.6i")
- }*/
+ }
 
  // Extra extra credit - adding a double to a complex works, but adding a complex
  // to a double does not. If you add an implicit conversion you can make this work
  // if you have time, write a test, and add an implicit to make it work
 
  // UNCOMMENT BELOW
- /*test ("Add a complex to a double") {
+ test ("Add a complex to a double") {
  val complex = 5.6 + new ComplexNum(3.4, 4.5)
 
  complex.real should be (9)
  complex.imaginary should be (4.5)
- }*/
+ }
 }