Add test to check behaviour if no modules are detected.

Author: dualspiral

build.gradle

@@ -26,7 +26,7 @@ dependencies {
     compile "ninja.leaping.configurate:configurate-core:3.1"
 
     testCompile "junit:junit:4.12"
-    testCompile "org.mockito:mockito-all:1.10.19"
+    testCompile "org.mockito:mockito-core:1.10.19"
     testCompile "org.powermock:powermock-module-junit4:1.6.4"
     testCompile "org.powermock:powermock-api-mockito:1.6.4"
 }

src/main/java/uk/co/drnaylor/quickstart/ModuleContainer.java

@@ -104,11 +104,6 @@ public static ModuleContainer.Builder builder() {
     private <N extends ConfigurationNode> ModuleContainer(ConfigurationLoader<N> configurationLoader, ClassLoader loader, String packageBase, ModuleConstructor constructor) throws QuickStartModuleDiscoveryException {
 
         try {
-            Preconditions.checkNotNull(configurationLoader);
-            Preconditions.checkNotNull(loader);
-            Preconditions.checkNotNull(packageBase);
-            Preconditions.checkNotNull(constructor);
-
             this.config = new SystemConfig<>(configurationLoader);
             this.constructor = constructor;
             this.classLoader = loader;
@@ -123,7 +118,7 @@ private <N extends ConfigurationNode> ModuleContainer(ConfigurationLoader<N> con
     /**
      * Starts discovery of modules.
      */
-    private void discoverModules() throws IOException {
+    private void discoverModules() throws IOException, QuickStartModuleDiscoveryException {
         Preconditions.checkState(currentPhase == ConstructionPhase.INITALISED);
         currentPhase = ConstructionPhase.DISCOVERING;
 
@@ -133,6 +128,10 @@ private void discoverModules() throws IOException {
                 .filter(Module.class::isAssignableFrom)
                 .map(x -> (Class<? extends Module>)x.asSubclass(Module.class)).collect(Collectors.toSet());
 
+        if (modules.isEmpty()) {
+            throw new QuickStartModuleDiscoveryException("No modules were found", null);
+        }
+
         // Put the modules into the discoverer.
         modules.forEach(modulePopulator);
 

src/test/java/uk/co/drnaylor/quickstart/tests/modules/exceptions/notamodule/NotAModule.java

@@ -0,0 +1,8 @@
+/*
+ * This file is part of QuickStart Module Loader, licensed under the MIT License (MIT). See the LICENSE.txt file
+ * at the root of this project for more details.
+ */
+package uk.co.drnaylor.quickstart.tests.modules.exceptions.notamodule;
+
+public class NotAModule {
+}

src/test/java/uk/co/drnaylor/quickstart/tests/tests/ModuleContainerConstructionTests.java

@@ -4,7 +4,9 @@
  */
 package uk.co.drnaylor.quickstart.tests.tests;
 
+import org.junit.Rule;
 import org.junit.Test;
+import org.junit.rules.ExpectedException;
 import uk.co.drnaylor.quickstart.ModuleContainer;
 import uk.co.drnaylor.quickstart.config.ModulesConfigAdapter;
 import uk.co.drnaylor.quickstart.config.SimpleNodeConfigAdapter;
@@ -17,6 +19,17 @@
 
 public class ModuleContainerConstructionTests extends FakeLoaderTests {
 
+    @Rule
+    public ExpectedException expectedException = ExpectedException.none();
+
+    @Test
+    public void testThatNoModulesThrow() throws Exception {
+        expectedException.expect(QuickStartModuleDiscoveryException.class);
+        expectedException.expectMessage("Unable to start QuickStart");
+
+        getContainer("uk.co.drnaylor.quickstart.tests.modules.exceptions.notamodule");
+    }
+
     @Test(expected = QuickStartModuleLoaderException.Construction.class)
     public void testThatUnconstructableModulesThrow() throws QuickStartModuleDiscoveryException, QuickStartModuleLoaderException.Enabling, QuickStartModuleLoaderException.Construction {
         getContainer("uk.co.drnaylor.quickstart.tests.modules.exceptions.construction").loadModules(true);