improve error messages

Author: russgold

kubernetes/src/test/java/oracle/kubernetes/operator/create/CreateOperatorGeneratedFilesTestBase.java

@@ -41,7 +41,7 @@
 import static oracle.kubernetes.operator.utils.YamlUtils.yamlEqualTo;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.is;
-import static org.hamcrest.Matchers.nullValue;
+import static org.junit.Assert.fail;
 
 import io.kubernetes.client.models.ExtensionsV1beta1Deployment;
 import io.kubernetes.client.models.V1ConfigMap;
@@ -231,19 +231,18 @@ protected ExtensionsV1beta1Deployment getExpectedWeblogicOperatorDeployment() {
 
   @Test
   public void generatesCorrect_externalWeblogicOperatorService() {
-    V1Service actual = getActualExternalWeblogicOperatorService();
     V1Service expected = getExpectedExternalWeblogicOperatorService();
-    if (expected == null) {
-      assertThat(actual, nullValue());
+    if (expected != null) {
+      assertThat(getGeneratedFiles().getExternalOperatorService(), yamlEqualTo(expected));
     } else {
-      assertThat(actual, yamlEqualTo(expected));
+      try {
+        getGeneratedFiles().getExternalOperatorService();
+        fail("Should not have found an external operator service yaml");
+      } catch (AssertionError ignored) {
+      }
     }
   }
 
-  private V1Service getActualExternalWeblogicOperatorService() {
-    return getGeneratedFiles().getExternalOperatorService();
-  }
-
   protected abstract V1Service getExpectedExternalWeblogicOperatorService();
 
   V1Service getExpectedExternalWeblogicOperatorService(

kubernetes/src/test/java/oracle/kubernetes/operator/utils/ParsedKubernetesYaml.java

@@ -217,9 +217,28 @@ public T find(String name) {
           }
         }
       }
+      if (result == null) {
+        throw new AssertionError(
+            "No instance with name '"
+                + name
+                + "' for the type '"
+                + this.getClass()
+                + "' among "
+                + getInstanceNames());
+      }
       return result;
     }
 
+    private String getInstanceNames() {
+      StringBuilder sb = new StringBuilder();
+      for (T instance : instances) {
+        sb.append(sb.length() == 0 ? "[" : ", ");
+        sb.append(getName(instance));
+      }
+      sb.append("]");
+      return sb.toString();
+    }
+
     protected T find(String name, String namespace) {
       T result = null;
       for (T instance : instances) {