added test for valid movement of black farmer

fh.fd.ci.client/src/main/java/de/fd/fh/FigureFarmer.java

@@ -15,12 +15,17 @@ public class FigureFarmer extends Figure
     {
         int rowDiff = src / fieldLength - dst / fieldLength; // hoch/runter
 
-        if (rowDiff > 1) // weißer Bauer nicht mehr als 1 Schritt nach "oben"
+        if (mColor == Color.Black)
+        {
+            rowDiff *= -1;
+        }
+
+        if (rowDiff > 1) // Bauer nicht mehr als 1 Schritt
         {
             return false;
         }
 
-        if (rowDiff <= 0) // weißer Bauer kein Schritt "runter"
+        if (rowDiff <= 0) // Bauer nur Schritte in erlaubte Richtung (weiß -> hoch, schwarz -> runter)
         {
             return false;
         }

fh.fd.ci.client/src/test/java/de/fd/fh/FigureFarmerTest.java

@@ -10,19 +10,30 @@ class FigureFarmerTest
 {
     Figure[] field = new Figure[Figure.fieldLength * Figure.fieldLength];
 
-    // weißer Bauer
     @ParameterizedTest
-    // row (src), col (src), row (dst), col (dst)
+    // color (0 white/1 black), row (src), col (src), row (dst), col (dst)
     @CsvSource({
-            "6, 0, 5, 0", // a2 -> a3
-            "4, 4, 3, 4"  // e4 -> e5
+            "0, 6, 0, 5, 0", // white: a2 -> a3
+            "0, 4, 4, 3, 4", // white: e4 -> e5
+
+            "1, 1, 0, 2, 0"  // black: a1 -> a2
     })
-    void whiteFarmerValidDestination(int srcRow, int srcCol, int dstRow, int dstCol)
+    void whiteFarmerValidDestination(int color, int srcRow, int srcCol, int dstRow, int dstCol)
     {
         int src = Figure.fieldLength * srcRow + srcCol;
         int dst = Figure.fieldLength * dstRow + dstCol;
 
-        Figure f = new FigureFarmer(FigureFarmer.Color.White);
+        Figure f = null;
+
+        if (color == 0)
+        {
+            f = new FigureFarmer(FigureFarmer.Color.White);
+        }
+        else if (color == 1)
+        {
+            f = new FigureFarmer(FigureFarmer.Color.Black);
+        }
+
         assertTrue(f.moveAllowed(src, dst, field));
     }