Support extensions of Browser - resolves #5

- Actor#using creates a Stage using the inferred type from the Browser argument
- Action and Assertion are parametrizable with <T extends Browser>
- Unchecked raw-type warnings in BrowserAssertions but these are ignored to preserve the DSL

Author: mrwilson

src/main/java/co/unruly/flick/browser/Stage.java

@@ -1,10 +1,10 @@
 package co.unruly.flick.browser;
 
-public class Stage {
-    private final Browser browser;
+public class Stage<T extends Browser> {
+    private final T browser;
     private Page page;
 
-    public Stage(Browser browser, Page page) {
+    public Stage(T browser, Page page) {
         this.browser = browser;
         this.page = page;
     }

src/main/java/co/unruly/flick/dsl/Action.java

@@ -2,6 +2,6 @@
 
 import co.unruly.flick.browser.Browser;
 
-public interface Action {
-    void performOn(Browser browser);
+public interface Action<T extends Browser> {
+    void performOn(T browser);
 }

src/main/java/co/unruly/flick/dsl/Actor.java

@@ -6,11 +6,11 @@
 import co.unruly.flick.browser.Stage;
 
 public interface Actor {
-    default Stage using(Browser browser, Page page) {
-        return new Stage(browser, page);
+    default <T extends Browser> Stage<T> using(T browser, Page page) {
+        return new Stage<>(browser, page);
     }
 
-    default Stage using(Browser browser, String url) {
-        return new Stage(browser, browser.load(url));
+    default <T extends Browser> Stage<T> using(T browser, String url) {
+        return new Stage<>(browser, browser.load(url));
     }
 }

src/main/java/co/unruly/flick/dsl/Assertion.java

@@ -2,6 +2,6 @@
 
 import co.unruly.flick.browser.Browser;
 
-public interface Assertion {
-    void check(Browser browser);
+public interface Assertion<T extends Browser> {
+    void check(T browser);
 }