Add proper unit tests for dependency-injection pattern

dependency-injection/src/test/java/com/iluwatar/dependency/injection/GuiceWizardTest.java

@@ -0,0 +1,78 @@
+package com.iluwatar.dependency.injection;
+
+import com.google.inject.AbstractModule;
+import com.google.inject.Guice;
+import com.google.inject.Injector;
+
+import org.junit.Test;
+
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+
+/**
+ * Date: 12/10/15 - 8:57 PM
+ *
+ * @author Jeroen Meulemeester
+ */
+public class GuiceWizardTest extends StdOutTest {
+
+  /**
+   * Test if the {@link GuiceWizard} smokes whatever instance of {@link Tobacco} is passed to him
+   * through the constructor parameter
+   */
+  @Test
+  public void testSmokeEveryThingThroughConstructor() throws Exception {
+
+    final Tobacco[] tobaccos = {
+        new OldTobyTobacco(), new RivendellTobacco(), new SecondBreakfastTobacco()
+    };
+
+    for (final Tobacco tobacco : tobaccos) {
+      final GuiceWizard guiceWizard = new GuiceWizard(tobacco);
+      guiceWizard.smoke();
+
+      // Verify if the wizard is smoking the correct tobacco ...
+      verify(getStdOutMock(), times(1)).println("GuiceWizard smoking " + tobacco.getClass().getSimpleName());
+
+      // ... and nothing else is happening.
+      verifyNoMoreInteractions(getStdOutMock());
+    }
+
+  }
+
+  /**
+   * Test if the {@link GuiceWizard} smokes whatever instance of {@link Tobacco} is passed to him
+   * through the Guice google inject framework
+   */
+  @Test
+  public void testSmokeEveryThingThroughInjectionFramework() throws Exception {
+
+    @SuppressWarnings("unchecked")
+    final Class<? extends Tobacco>[] tobaccos = new Class[]{
+        OldTobyTobacco.class, RivendellTobacco.class, SecondBreakfastTobacco.class
+    };
+
+    for (final Class<? extends Tobacco> tobaccoClass : tobaccos) {
+      // Configure the tobacco in the injection framework ...
+      final Injector injector = Guice.createInjector(new AbstractModule() {
+        @Override
+        protected void configure() {
+          bind(Tobacco.class).to(tobaccoClass);
+        }
+      });
+
+      // ... and create a new wizard with it
+      final GuiceWizard guiceWizard = injector.getInstance(GuiceWizard.class);
+      guiceWizard.smoke();
+
+      // Verify if the wizard is smoking the correct tobacco ...
+      verify(getStdOutMock(), times(1)).println("GuiceWizard smoking " + tobaccoClass.getSimpleName());
+
+      // ... and nothing else is happening.
+      verifyNoMoreInteractions(getStdOutMock());
+    }
+
+  }
+
+}