@@ -0,0 +1,677 @@
+package org.jboss.forge.furnace;%0A%0Aimport java.io.File;%0A%0Aimport org.jboss.forge.furnace.impl.FurnaceImpl;%0Aimport org.jboss.forge.furnace.repositories.AddonRepositoryMode;%0Aimport org.junit.Test;%0A%0Apublic class FurnaceImplTest%0A%7B%0A   @Test(expected = IllegalArgumentException.class)%0A   public void shouldValidateAddRepositoryArgumentMode() throws Exception %7B%0A      Furnace f = new FurnaceImpl();%0A      f.addRepository(null, new File(%22.%22));%0A   %7D%0A%0A   @Test(expected = IllegalArgumentException.class)%0A   public void shouldValidateAddRepositoryArgumentDirectory() throws Exception %7B%0A      Furnace f = new FurnaceImpl();%0A      f.addRepository(AddonRepositoryMode.IMMUTABLE, null);%0A   %7D%0A%7D%0A

Add tests to verify method argument validation