Add integration test. Run with ./gradlew runIntegrationTest

src/integration-test/java/IntegrationTest.java

@@ -0,0 +1,30 @@
+import org.apache.commons.io.FileUtils;
+
+import java.io.File;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * Entry point for running integration tests from within the IDE.
+ * This is <b>not</b> called when running integration tests directly from gradle.
+ */
+public class IntegrationTest {
+    public static void main(String[] args) throws Throwable {
+        // Prevent MC from grabbing our mouse during the test (it's not needed)
+        System.setProperty("fml.noGrab", "true");
+
+        // Make sure the test folder exists and is fresh
+        File gameDir = new File(System.getProperty("user.dir"), "integration-test");
+        if (gameDir.exists()) {
+            FileUtils.forceDelete(gameDir);
+        }
+        FileUtils.forceMkdir(gameDir);
+
+        // Set game dir to test folder and call regular entry point
+        List<String> argsList = new ArrayList<>(Arrays.asList(args));
+        argsList.add("--gameDir");
+        argsList.add(gameDir.getCanonicalPath());
+        GradleStart.main(argsList.toArray(new String[argsList.size()]));
+    }
+}