add rules acceptance test for junit4/ (#22)

* hint: only works for 4.9 <= junit < 5.0)

Signed-off-by: Andreas Schmid <[email protected]>

junit4/src/integTest/java/com/tngtech/test/java/junit/dataprovider/RuleAcceptanceTest.java

@@ -0,0 +1,48 @@
+package com.tngtech.test.java.junit.dataprovider;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.ClassRule;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TestWatcher;
+import org.junit.runner.Description;
+import org.junit.runner.RunWith;
+
+import com.tngtech.java.junit.dataprovider.DataProviderRunner;
+
+@RunWith(DataProviderRunner.class)
+public class RuleAcceptanceTest {
+
+    public static class SomeTestRule extends TestWatcher {
+        boolean started;
+
+        @Override
+        protected void starting(Description description) {
+            started = true;
+        }
+
+        @Override
+        protected void finished(Description description) {
+            assertThat(started).as("Rule was not started, but 'finished' called").isTrue();
+        }
+    }
+
+    @ClassRule
+    public static final SomeTestRule classRule = new SomeTestRule();
+
+    @Rule
+    public SomeTestRule rule = new SomeTestRule();
+
+    @Test
+    public void testClassRuleShouldBeStartedBeforeTest() {
+        // Expected:
+        assertThat(classRule.started).as("'@ClassRule' was not started").isTrue();
+    }
+
+    @Test
+    public void testRuleShouldBeStartedBeforeTest() {
+        // Expected:
+        assertThat(rule.started).as("'@Rule' was not started").isTrue();
+    }
+}