Add Unit Test for lazy init Guice providers

src/test/java/org/springframework/guice/module/DevelepmentStageInjectorTest.java

@@ -0,0 +1,81 @@
+package org.springframework.guice.module;
+
+import com.google.inject.*;
+import com.google.inject.Module;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.guice.annotation.EnableGuiceModules;
+import org.springframework.guice.annotation.InjectorFactory;
+
+import java.util.List;
+
+import static org.junit.Assert.assertFalse;
+
+public class DevelepmentStageInjectorTest {
+
+    @BeforeClass
+    public static void init() {
+        System.setProperty("spring.guice.stage", "DEVELOPMENT");
+    }
+
+    @AfterClass
+    public static void cleanup() {
+        System.clearProperty("spring.guice.stage");
+    }
+
+    @Test
+    public void testLazyInitBean() {
+        AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(DevelepmentStageInjectorTest.ModulesConfig.class);
+        TestGuiceModule testGuiceModule = context.getBean(TestGuiceModule.class);
+        assertFalse(testGuiceModule.getProviderExecuted());
+        context.close();
+    }
+
+    @Configuration
+    @EnableGuiceModules
+    static class ModulesConfig {
+        @Bean
+        public TestGuiceModule testGuiceModule() {
+            return new TestGuiceModule();
+        }
+
+        @Bean
+        public InjectorFactory injectorFactory() {
+            return new TestDevelopmentStageInjectorFactory();
+        }
+
+    }
+
+    static class TestGuiceModule extends AbstractModule {
+        private boolean providerExecuted = false;
+
+        public boolean getProviderExecuted() {
+            return this.providerExecuted;
+        }
+
+        @Override
+        protected void configure() {
+        }
+
+        @Provides
+        @Singleton
+        public GuiceToken guiceToken() {
+            this.providerExecuted = true;
+            return new GuiceToken();
+        }
+    }
+
+    static class TestDevelopmentStageInjectorFactory implements InjectorFactory {
+
+        @Override
+        public Injector createInjector(List<Module> modules) {
+            return Guice.createInjector(Stage.DEVELOPMENT, modules);
+        }
+    }
+
+    static class GuiceToken {}
+}