1 files changed, 133 insertions, 0 deletions
diff --git a/api/src/test/java/io/opencensus/stats/NoopStatsTest.java b/api/src/test/java/io/opencensus/stats/NoopStatsTest.java
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+++ b/api/src/test/java/io/opencensus/stats/NoopStatsTest.java
@@ -0,0 +1,133 @@
+/*
+ * Copyright 2017, OpenCensus Authors
+ *
+ * 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 io.opencensus.stats;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import io.opencensus.stats.Measure.MeasureDouble;
+import io.opencensus.tags.Tag;
+import io.opencensus.tags.TagContext;
+import io.opencensus.tags.TagKey;
+import io.opencensus.tags.TagValue;
+import java.util.Collections;
+import java.util.Iterator;
+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 NoopStats}. Tests for {@link NoopStats#newNoopViewManager} are in {@link
+ * NoopViewManagerTest}
+ */
+@RunWith(JUnit4.class)
+public final class NoopStatsTest {
+  private static final Tag TAG = Tag.create(TagKey.create("key"), TagValue.create("value"));
+  private static final MeasureDouble MEASURE =
+      Measure.MeasureDouble.create("my measure", "description", "s");
+
+  private final TagContext tagContext =
+      new TagContext() {
+
+        @Override
+        protected Iterator<Tag> getIterator() {
+          return Collections.<Tag>singleton(TAG).iterator();
+        }
+      };
+
+  @Rule public final ExpectedException thrown = ExpectedException.none();
+
+  @Test
+  public void noopStatsComponent() {
+    assertThat(NoopStats.newNoopStatsComponent().getStatsRecorder())
+        .isSameAs(NoopStats.getNoopStatsRecorder());
+    assertThat(NoopStats.newNoopStatsComponent().getViewManager())
+        .isInstanceOf(NoopStats.newNoopViewManager().getClass());
+  }
+
+  @Test
+  public void noopStatsComponent_GetState() {
+    assertThat(NoopStats.newNoopStatsComponent().getState())
+        .isEqualTo(StatsCollectionState.DISABLED);
+  }
+
+  @Test
+  @SuppressWarnings("deprecation")
+  public void noopStatsComponent_SetState_IgnoresInput() {
+    StatsComponent noopStatsComponent = NoopStats.newNoopStatsComponent();
+    noopStatsComponent.setState(StatsCollectionState.ENABLED);
+    assertThat(noopStatsComponent.getState()).isEqualTo(StatsCollectionState.DISABLED);
+  }
+
+  @Test
+  @SuppressWarnings("deprecation")
+  public void noopStatsComponent_SetState_DisallowsNull() {
+    StatsComponent noopStatsComponent = NoopStats.newNoopStatsComponent();
+    thrown.expect(NullPointerException.class);
+    noopStatsComponent.setState(null);
+  }
+
+  @Test
+  @SuppressWarnings("deprecation")
+  public void noopStatsComponent_DisallowsSetStateAfterGetState() {
+    StatsComponent noopStatsComponent = NoopStats.newNoopStatsComponent();
+    noopStatsComponent.setState(StatsCollectionState.DISABLED);
+    noopStatsComponent.getState();
+    thrown.expect(IllegalStateException.class);
+    thrown.expectMessage("State was already read, cannot set state.");
+    noopStatsComponent.setState(StatsCollectionState.ENABLED);
+  }
+
+  @Test
+  public void noopStatsRecorder_PutAttachmentNullKey() {
+    MeasureMap measureMap = NoopStats.getNoopStatsRecorder().newMeasureMap();
+    thrown.expect(NullPointerException.class);
+    thrown.expectMessage("key");
+    measureMap.putAttachment(null, "value");
+  }
+
+  @Test
+  public void noopStatsRecorder_PutAttachmentNullValue() {
+    MeasureMap measureMap = NoopStats.getNoopStatsRecorder().newMeasureMap();
+    thrown.expect(NullPointerException.class);
+    thrown.expectMessage("value");
+    measureMap.putAttachment("key", null);
+  }
+
+  // The NoopStatsRecorder should do nothing, so this test just checks that record doesn't throw an
+  // exception.
+  @Test
+  public void noopStatsRecorder_Record() {
+    NoopStats.getNoopStatsRecorder().newMeasureMap().put(MEASURE, 5).record(tagContext);
+  }
+
+  // The NoopStatsRecorder should do nothing, so this test just checks that record doesn't throw an
+  // exception.
+  @Test
+  public void noopStatsRecorder_RecordWithCurrentContext() {
+    NoopStats.getNoopStatsRecorder().newMeasureMap().put(MEASURE, 6).record();
+  }
+
+  @Test
+  public void noopStatsRecorder_Record_DisallowNullTagContext() {
+    MeasureMap measureMap = NoopStats.getNoopStatsRecorder().newMeasureMap();
+    thrown.expect(NullPointerException.class);
+    thrown.expectMessage("tags");
+    measureMap.record(null);
+  }
+}