Fix ResultMatchers#hasFailureContaining

src/main/java/org/junit/experimental/results/ResultMatchers.java

@@ -5,6 +5,8 @@
 import org.hamcrest.Matcher;
 import org.hamcrest.TypeSafeMatcher;
 
+import static org.hamcrest.CoreMatchers.equalTo;
+
 /**
  * Matchers on a PrintableResult, to enable JUnit self-tests.
  * For example:
@@ -34,14 +36,21 @@ public static Matcher<PrintableResult> isSuccessful() {
      * Matches if there are {@code count} failures
      */
     public static Matcher<PrintableResult> failureCountIs(final int count) {
+        return failureCount(equalTo(count));
+    }
+
+    /**
+     * Matches if the number of failures matches {@code countMatcher}
+     */
+    public static Matcher<PrintableResult> failureCount(final Matcher<Integer> countMatcher) {
         return new TypeSafeMatcher<PrintableResult>() {
             public void describeTo(Description description) {
-                description.appendText("has " + count + " failures");
+                description.appendText("has a number of failures matching " + countMatcher);
             }
 
             @Override
             public boolean matchesSafely(PrintableResult item) {
-                return item.failureCount() == count;
+                return countMatcher.matches(item.failureCount());
             }
         };
     }
@@ -66,9 +75,9 @@ public void describeTo(Description description) {
      * contains {@code string}
      */
     public static Matcher<PrintableResult> hasFailureContaining(final String string) {
-        return new BaseMatcher<PrintableResult>() {
-            public boolean matches(Object item) {
-                return item.toString().contains(string);
+        return new TypeSafeMatcher<PrintableResult>() {
+            public boolean matchesSafely(PrintableResult item) {
+                return item.failureCount() > 0 && item.toString().contains(string);
             }
 
             public void describeTo(Description description) {

src/test/java/org/junit/tests/experimental/results/ResultMatchersTest.java

@@ -1,23 +1,56 @@
 package org.junit.tests.experimental.results;
 
-import static org.hamcrest.CoreMatchers.containsString;
-import static org.hamcrest.CoreMatchers.is;
-import static org.junit.Assert.assertThat;
-
 import org.junit.Test;
+import org.junit.experimental.results.PrintableResult;
 import org.junit.experimental.results.ResultMatchers;
 import org.junit.experimental.theories.Theory;
+import org.junit.runner.Description;
+import org.junit.runner.notification.Failure;
+
+import java.util.ArrayList;
+import java.util.Collections;
+
+import static org.hamcrest.CoreMatchers.containsString;
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
 
 public class ResultMatchersTest {
+
     @Test
     public void hasFailuresHasGoodDescription() {
         assertThat(ResultMatchers.failureCountIs(3).toString(),
-                is("has 3 failures"));
+                is("has a number of failures matching <3>"));
     }
 
     @Theory
     public void hasFailuresDescriptionReflectsInput(int i) {
         assertThat(ResultMatchers.failureCountIs(i).toString(),
                 containsString("" + i));
     }
+
+    @Test
+    public void hasFailureContaining_givenResultWithNoFailures() {
+        PrintableResult resultWithNoFailures = new PrintableResult(new ArrayList<Failure>());
+
+        assertThat(ResultMatchers.hasFailureContaining("").matches(resultWithNoFailures), is(false));
+    }
+
+    @Test
+    public void hasFailureContaining_givenResultWithOneFailure() {
+        PrintableResult resultWithOneFailure = new PrintableResult(Collections.singletonList(
+                new Failure(Description.EMPTY, new RuntimeException("my failure"))));
+
+        assertThat(ResultMatchers.hasFailureContaining("my failure").matches(resultWithOneFailure), is(true));
+        assertThat(ResultMatchers.hasFailureContaining("his failure").matches(resultWithOneFailure), is(false));
+    }
+
+    @Test
+    public void testFailureCount() {
+        PrintableResult resultWithOneFailure = new PrintableResult(Collections.singletonList(
+                new Failure(Description.EMPTY, new RuntimeException("failure 1"))));
+
+        assertThat(ResultMatchers.failureCount(equalTo(3)).matches(resultWithOneFailure), is(false));
+        assertThat(ResultMatchers.failureCount(equalTo(1)).matches(resultWithOneFailure), is(true));
+    }
 }