allow to set a custom/fake Server fix #430

Author: jknack

jooby/src/main/java/org/jooby/Jooby.java

@@ -653,6 +653,8 @@ public EnvDep(final Predicate<String> predicate, final Consumer<Config> callback
   /** Bean parser . */
   private Optional<Parser> beanParser = Optional.empty();
 
+  private ServerLookup server = new ServerLookup();
+
   public Jooby() {
     this(null);
   }
@@ -665,7 +667,7 @@ public Jooby() {
    */
   public Jooby(final String prefix) {
     this.prefix = prefix;
-    use(new ServerLookup());
+    use(server);
   }
 
   /**
@@ -679,6 +681,25 @@ public Jooby use(final Jooby app) {
     return use(Optional.empty(), app);
   }
 
+  /**
+   * Use the provided HTTP server.
+   *
+   * @param server Server.
+   * @return This jooby instance.
+   */
+  public Jooby server(final Class<? extends Server> server) {
+    requireNonNull(server, "Server required.");
+    // remove server lookup
+    List<Object> tmp = bag.stream()
+        .skip(1)
+        .collect(Collectors.toList());
+    tmp.add(0,
+        (Module) (env, conf, binder) -> binder.bind(Server.class).to(server).asEagerSingleton());
+    bag.clear();
+    bag.addAll(tmp);
+    return this;
+  }
+
   /**
    * Import content from provide application (routes, parsers/renderers, start/stop callbacks, ...
    * etc.). Routes will be mounted at the provided path.

jooby/src/test/java/org/jooby/issues/Issue430.java

@@ -0,0 +1,31 @@
+package org.jooby.issues;
+
+import org.jooby.Jooby;
+import org.jooby.spi.Server;
+import org.junit.Test;
+
+public class Issue430 {
+
+  public static class NOOP implements Server {
+
+    @Override
+    public void start() throws Exception {
+      throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public void stop() throws Exception {
+    }
+
+    @Override
+    public void join() throws InterruptedException {
+    }
+
+  }
+
+  @Test(expected = UnsupportedOperationException.class)
+  public void customServer() throws Throwable {
+    new Jooby().server(NOOP.class).start();
+  }
+
+}