Add more tests to external code repo

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=131406104

javatests/google/registry/monitoring/metrics/StoredMetricTest.java

@@ -0,0 +1,100 @@
+// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.monitoring.metrics;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
+import org.joda.time.Instant;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+import org.junit.runner.RunWith;
+import org.junit.runners.JUnit4;
+
+/** Unit tests for {@link StoredMetric}. */
+@RunWith(JUnit4.class)
+public class StoredMetricTest {
+
+  @Rule
+  public final ExpectedException thrown = ExpectedException.none();
+
+  @Test
+  public void testGetCardinality_reflectsCurrentCardinality() {
+    StoredMetric<Boolean> smallMetric =
+        new StoredMetric<>(
+            "/metric", "description", "vdn", ImmutableSet.<LabelDescriptor>of(), Boolean.class);
+    assertThat(smallMetric.getCardinality()).isEqualTo(0);
+
+    smallMetric.set(true);
+
+    assertThat(smallMetric.getCardinality()).isEqualTo(1);
+
+    StoredMetric<Boolean> dimensionalMetric =
+        new StoredMetric<>(
+            "/metric",
+            "description",
+            "vdn",
+            ImmutableSet.of(LabelDescriptor.create("foo", "bar")),
+            Boolean.class);
+
+    dimensionalMetric.set(true, "test_value1");
+    dimensionalMetric.set(true, "test_value2");
+
+    assertThat(dimensionalMetric.getCardinality()).isEqualTo(2);
+  }
+
+  @Test
+  public void testSet_wrongNumberOfLabels_throwsException() {
+    StoredMetric<Boolean> dimensionalMetric =
+        new StoredMetric<>(
+            "/metric",
+            "description",
+            "vdn",
+            ImmutableSet.of(
+                LabelDescriptor.create("label1", "bar"), LabelDescriptor.create("label2", "bar")),
+            Boolean.class);
+
+    thrown.expect(IllegalArgumentException.class);
+    thrown.expectMessage("The count of labelValues must be equal to");
+    dimensionalMetric.set(true, "foo");
+  }
+
+  @Test
+  public void testSet_setsValue() {
+    StoredMetric<Boolean> metric =
+        new StoredMetric<>(
+            "/metric",
+            "description",
+            "vdn",
+            ImmutableSet.of(LabelDescriptor.create("label1", "bar")),
+            Boolean.class);
+
+    assertThat(metric.getTimestampedValues()).isEmpty();
+
+    metric.set(true, ImmutableList.of("test_value1"));
+    assertThat(metric.getTimestampedValues(new Instant(1337)))
+        .containsExactly(
+            MetricPoint.create(metric, ImmutableList.of("test_value1"), new Instant(1337), true));
+
+    metric.set(false, ImmutableList.of("test_value1"));
+    metric.set(true, ImmutableList.of("test_value2"));
+    assertThat(metric.getTimestampedValues(new Instant(1338)))
+        .containsExactly(
+            MetricPoint.create(metric, ImmutableList.of("test_value1"), new Instant(1338), false),
+            MetricPoint.create(metric, ImmutableList.of("test_value2"), new Instant(1338), true));
+  }
+}