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// Copyright 2016 The Bazel 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 com.google.devtools.build.lib.runtime;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
import static org.mockito.Mockito.when;
import com.google.common.collect.ImmutableSet;
import com.google.devtools.build.lib.actions.Action;
import com.google.devtools.build.lib.actions.ActionCompletionEvent;
import com.google.devtools.build.lib.actions.ActionExecutionMetadata;
import com.google.devtools.build.lib.actions.ActionOwner;
import com.google.devtools.build.lib.actions.ActionStartedEvent;
import com.google.devtools.build.lib.actions.ActionStatusMessage;
import com.google.devtools.build.lib.actions.Artifact;
import com.google.devtools.build.lib.actions.Root;
import com.google.devtools.build.lib.analysis.ConfiguredTarget;
import com.google.devtools.build.lib.buildtool.buildevent.TestFilteringCompleteEvent;
import com.google.devtools.build.lib.cmdline.Label;
import com.google.devtools.build.lib.skyframe.LoadingPhaseStartedEvent;
import com.google.devtools.build.lib.skyframe.PackageProgressReceiver;
import com.google.devtools.build.lib.testutil.FoundationTestCase;
import com.google.devtools.build.lib.testutil.ManualClock;
import com.google.devtools.build.lib.util.Pair;
import com.google.devtools.build.lib.util.io.LoggingTerminalWriter;
import com.google.devtools.build.lib.vfs.Path;
import com.google.devtools.build.lib.vfs.PathFragment;
import com.google.devtools.build.lib.view.test.TestStatus.BlazeTestStatus;
import java.io.IOException;
import java.util.concurrent.TimeUnit;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;
import org.mockito.Mockito;
/**
* Tests {@link ExperimentalStateTracker}.
*/
@RunWith(JUnit4.class)
public class ExperimentalStateTrackerTest extends FoundationTestCase {
private Action mockAction(String progressMessage, String primaryOutput) {
Path path = outputBase.getRelative(new PathFragment(primaryOutput));
Artifact artifact = new Artifact(path, Root.asSourceRoot(path));
Action action = Mockito.mock(Action.class);
when(action.getProgressMessage()).thenReturn(progressMessage);
when(action.getPrimaryOutput()).thenReturn(artifact);
return action;
}
private int longestLine(String output) {
int maxLength = 0;
for (String line : output.split("\n")) {
maxLength = Math.max(maxLength, line.length());
}
return maxLength;
}
@Test
public void testLoadingActivity() throws IOException {
// During loading phase, state and activity, as reported by the PackageProgressReceiver,
// should be visible in the progress bar.
String state = "42 packages loaded";
String activity = "currently loading //src/foo/bar and 17 more";
PackageProgressReceiver progress = Mockito.mock(PackageProgressReceiver.class);
when(progress.progressState()).thenReturn(new Pair<String, String>(state, activity));
ManualClock clock = new ManualClock();
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock);
stateTracker.loadingStarted(new LoadingPhaseStartedEvent(progress));
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
assertTrue(
"Output should indicate that we are in the loading phase, but was:\n" + output,
output.contains("Loading"));
assertTrue(
"Output should contain loading state '" + state + "', but was:\n" + output,
output.contains(state));
assertTrue(
"Output should contain loading state '" + activity + "', but was:\n" + output,
output.contains(activity));
}
@Test
public void testActionVisible() throws IOException {
// If there is only one action running, it should be visible
// somewhere in the progress bar, and also the short version thereof.
String message = "Building foo";
ManualClock clock = new ManualClock();
clock.advanceMillis(120000);
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock);
stateTracker.actionStarted(new ActionStartedEvent(mockAction(message, "bar/foo"), 123456789));
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
assertTrue(
"Action message '" + message + "' should be present in output: " + output,
output.contains(message));
terminalWriter = new LoggingTerminalWriter();
stateTracker.writeProgressBar(terminalWriter, /* shortVersion=*/ true);
output = terminalWriter.getTranscript();
assertTrue(
"Action message '" + message + "' should be present in short output: " + output,
output.contains(message));
}
@Test
public void testCompletedActionNotShown() throws IOException {
// Completed actions should not be reported in the progress bar, nor in the
// short progress bar.
String messageFast = "Running quick action";
String messageSlow = "Running slow action";
ManualClock clock = new ManualClock();
clock.advanceMillis(120000);
Action fastAction = mockAction(messageFast, "foo/fast");
Action slowAction = mockAction(messageSlow, "bar/slow");
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock);
stateTracker.actionStarted(new ActionStartedEvent(fastAction, 123456789));
stateTracker.actionStarted(new ActionStartedEvent(slowAction, 123456999));
stateTracker.actionCompletion(new ActionCompletionEvent(20, fastAction));
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
assertFalse(
"Completed action '" + messageFast + "' should not be present in output: " + output,
output.contains(messageFast));
assertTrue(
"Only running action '" + messageSlow + "' should be present in output: " + output,
output.contains(messageSlow));
terminalWriter = new LoggingTerminalWriter();
stateTracker.writeProgressBar(terminalWriter, /* shortVersion=*/ true);
output = terminalWriter.getTranscript();
assertFalse(
"Completed action '" + messageFast + "' should not be present in short output: " + output,
output.contains(messageFast));
assertTrue(
"Only running action '" + messageSlow + "' should be present in short output: " + output,
output.contains(messageSlow));
}
@Test
public void testOldestActionVisible() throws IOException {
// The earliest-started action is always visible somehow in the progress bar
// and its short version.
String messageOld = "Running the first-started action";
ManualClock clock = new ManualClock();
clock.advanceMillis(120000);
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock);
stateTracker.actionStarted(
new ActionStartedEvent(mockAction(messageOld, "bar/foo"), 123456789));
for (int i = 0; i < 30; i++) {
stateTracker.actionStarted(
new ActionStartedEvent(
mockAction("Other action " + i, "some/other/actions/number" + i), 123456790 + i));
}
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
assertTrue(
"Longest running action '" + messageOld + "' should be visible in output: " + output,
output.contains(messageOld));
terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter, /* shortVersion=*/ true);
output = terminalWriter.getTranscript();
assertTrue(
"Longest running action '" + messageOld + "' should be visible in short output: " + output,
output.contains(messageOld));
}
@Test
public void testSampleSize() throws IOException {
// Verify that the number of actions shown in the progress bar can be set as sample size.
ManualClock clock = new ManualClock();
clock.advanceMillis(TimeUnit.SECONDS.toMillis(123));
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock);
clock.advanceMillis(TimeUnit.SECONDS.toMillis(2));
// Start 10 actions (numbered 0 to 9).
for (int i = 0; i < 10; i++) {
clock.advanceMillis(TimeUnit.SECONDS.toMillis(1));
Action action = mockAction("Performing action A" + i + ".", "action_A" + i + ".out");
stateTracker.actionStarted(new ActionStartedEvent(action, clock.nanoTime()));
}
// For various sample sizes verify the progress bar
for (int i = 1; i < 11; i++) {
stateTracker.setSampleSize(i);
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
assertTrue(
"Action " + (i - 1) + " should still be shown in the output: '" + output,
output.contains("A" + (i - 1) + "."));
assertFalse(
"Action " + i + " should not be shown in the output: " + output,
output.contains("A" + i + "."));
if (i < 10) {
assertTrue("Ellipsis symbol should be shown in output: " + output, output.contains("..."));
} else {
assertFalse(
"Ellipsis symbol should not be shown in output: " + output, output.contains("..."));
}
}
}
@Test
public void testTimesShown() throws IOException {
// For sufficiently long running actions, the time that has passed since their start is shown.
// In the short version of the progress bar, this should be true at least for the oldest action.
ManualClock clock = new ManualClock();
clock.advanceMillis(TimeUnit.SECONDS.toMillis(123));
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock);
clock.advanceMillis(TimeUnit.SECONDS.toMillis(2));
stateTracker.actionStarted(
new ActionStartedEvent(mockAction("First action", "foo"), clock.nanoTime()));
clock.advanceMillis(TimeUnit.SECONDS.toMillis(7));
stateTracker.actionStarted(
new ActionStartedEvent(mockAction("Second action", "bar"), clock.nanoTime()));
clock.advanceMillis(TimeUnit.SECONDS.toMillis(20));
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
assertTrue(
"Runtime of first action should be visible in output: " + output, output.contains("27s"));
assertTrue(
"Runtime of second action should be visible in output: " + output, output.contains("20s"));
terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter, /* shortVersion=*/ true);
output = terminalWriter.getTranscript();
assertTrue(
"Runtime of first action should be visible in short output: " + output,
output.contains("27s"));
}
@Test
public void initialProgressBarTimeIndependent() {
ManualClock clock = new ManualClock();
clock.advanceMillis(TimeUnit.SECONDS.toMillis(123));
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock);
assertFalse(
"Initial progress status should be time independent",
stateTracker.progressBarTimeDependent());
}
@Test
public void runningActionTimeIndependent() {
ManualClock clock = new ManualClock();
clock.advanceMillis(TimeUnit.SECONDS.toMillis(123));
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock);
clock.advanceMillis(TimeUnit.SECONDS.toMillis(1));
stateTracker.actionStarted(
new ActionStartedEvent(mockAction("Some action", "foo"), clock.nanoTime()));
assertTrue(
"Progress bar showing a running action should be time dependent",
stateTracker.progressBarTimeDependent());
}
@Test
public void testCountVisible() throws Exception {
// The test count should be visible in the status bar, as well as the short status bar
ManualClock clock = new ManualClock();
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock);
TestFilteringCompleteEvent filteringComplete = Mockito.mock(TestFilteringCompleteEvent.class);
Label labelA = Label.parseAbsolute("//foo/bar:baz");
ConfiguredTarget targetA = Mockito.mock(ConfiguredTarget.class);
when(targetA.getLabel()).thenReturn(labelA);
ConfiguredTarget targetB = Mockito.mock(ConfiguredTarget.class);
when(filteringComplete.getTestTargets()).thenReturn(ImmutableSet.of(targetA, targetB));
TestSummary testSummary = Mockito.mock(TestSummary.class);
when(testSummary.getTarget()).thenReturn(targetA);
stateTracker.testFilteringComplete(filteringComplete);
stateTracker.testSummary(testSummary);
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
assertTrue(
"Test count should be visible in output: " + output, output.contains(" 1 / 2 tests"));
terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter, /* shortVersion=*/ true);
output = terminalWriter.getTranscript();
assertTrue(
"Test count should be visible in short output: " + output, output.contains(" 1 / 2 tests"));
}
@Test
public void testPassedVisible() throws Exception {
// The last test should still be visible in the long status bar, and colored as ok if it passed.
ManualClock clock = new ManualClock();
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock);
TestFilteringCompleteEvent filteringComplete = Mockito.mock(TestFilteringCompleteEvent.class);
Label labelA = Label.parseAbsolute("//foo/bar:baz");
ConfiguredTarget targetA = Mockito.mock(ConfiguredTarget.class);
when(targetA.getLabel()).thenReturn(labelA);
ConfiguredTarget targetB = Mockito.mock(ConfiguredTarget.class);
when(filteringComplete.getTestTargets()).thenReturn(ImmutableSet.of(targetA, targetB));
TestSummary testSummary = Mockito.mock(TestSummary.class);
when(testSummary.getStatus()).thenReturn(BlazeTestStatus.PASSED);
when(testSummary.getTarget()).thenReturn(targetA);
stateTracker.testFilteringComplete(filteringComplete);
stateTracker.testSummary(testSummary);
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter();
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
String expected = LoggingTerminalWriter.OK + labelA;
assertTrue(
"Sequence '" + expected + "' should be present in colored progress bar: " + output,
output.contains(expected));
}
@Test
public void testFailedVisible() throws Exception {
// The last test should still be visible in the long status bar, and colored as fail if it
// did not pass.
ManualClock clock = new ManualClock();
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock);
TestFilteringCompleteEvent filteringComplete = Mockito.mock(TestFilteringCompleteEvent.class);
Label labelA = Label.parseAbsolute("//foo/bar:baz");
ConfiguredTarget targetA = Mockito.mock(ConfiguredTarget.class);
when(targetA.getLabel()).thenReturn(labelA);
ConfiguredTarget targetB = Mockito.mock(ConfiguredTarget.class);
when(filteringComplete.getTestTargets()).thenReturn(ImmutableSet.of(targetA, targetB));
TestSummary testSummary = Mockito.mock(TestSummary.class);
when(testSummary.getStatus()).thenReturn(BlazeTestStatus.FAILED);
when(testSummary.getTarget()).thenReturn(targetA);
stateTracker.testFilteringComplete(filteringComplete);
stateTracker.testSummary(testSummary);
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter();
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
String expected = LoggingTerminalWriter.FAIL + labelA;
assertTrue(
"Sequence '" + expected + "' should be present in colored progress bar: " + output,
output.contains(expected));
}
@Test
public void testSensibleShortening() throws Exception {
// Verify that in the typical case, we shorten the progress message by shortening
// the path implicit in it, that can also be extracted from the label. In particular,
// the parts
ManualClock clock = new ManualClock();
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock, 70);
Action action = mockAction(
"Building some/very/very/long/path/for/some/library/directory/foo.jar (42 source files)",
"/home/user/bazel/out/abcdef/some/very/very/long/path/for/some/library/directory/foo.jar");
Label label =
Label.parseAbsolute("//some/very/very/long/path/for/some/library/directory:libfoo");
ActionOwner owner = ActionOwner.create(label, null, null, null, null, null, "fedcba", null);
when(action.getOwner()).thenReturn(owner);
clock.advanceMillis(TimeUnit.SECONDS.toMillis(3));
stateTracker.actionStarted(new ActionStartedEvent(action, clock.nanoTime()));
clock.advanceMillis(TimeUnit.SECONDS.toMillis(5));
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
assertTrue(
"Progress bar should contain 'Building ', but was:\n" + output,
output.contains("Building "));
assertTrue(
"Progress bar should contain 'foo.jar (42 source files)', but was:\n" + output,
output.contains("foo.jar (42 source files)"));
}
@Test
public void testActionStrategyVisible() throws Exception {
// verify that, if a strategy was reported for a shown action, it is visible
// in the progress bar.
String strategy = "verySpecialStrategy";
String primaryOutput = "some/path/to/a/file";
ManualClock clock = new ManualClock();
Path path = outputBase.getRelative(new PathFragment(primaryOutput));
Artifact artifact = new Artifact(path, Root.asSourceRoot(path));
ActionExecutionMetadata actionMetadata = Mockito.mock(ActionExecutionMetadata.class);
when(actionMetadata.getPrimaryOutput()).thenReturn(artifact);
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock);
stateTracker.actionStarted(
new ActionStartedEvent(mockAction("Some random action", primaryOutput), clock.nanoTime()));
stateTracker.actionStatusMessage(ActionStatusMessage.runningStrategy(actionMetadata, strategy));
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
assertTrue(
"Output should mention strategy '" + strategy + "', but was: " + output,
output.contains(strategy));
}
private void doTestOutputLength(boolean withTest, int actions) throws Exception {
// If we target 70 characters, then there should be enough space to both,
// keep the line limit, and show the local part of the running actions and
// the passed test.
ManualClock clock = new ManualClock();
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock, 70);
Action foobuildAction = mockAction(
"Building //src/some/very/long/path/long/long/long/long/long/long/long/foo/foobuild.jar",
"//src/some/very/long/path/long/long/long/long/long/long/long/foo:foobuild");
Action bazbuildAction = mockAction(
"Building //src/some/very/long/path/long/long/long/long/long/long/long/baz/bazbuild.jar",
"//src/some/very/long/path/long/long/long/long/long/long/long/baz:bazbuild");
Label bartestLabel =
Label.parseAbsolute(
"//src/another/very/long/long/path/long/long/long/long/long/long/long/long/bars:bartest");
ConfiguredTarget bartestTarget = Mockito.mock(ConfiguredTarget.class);
when(bartestTarget.getLabel()).thenReturn(bartestLabel);
TestFilteringCompleteEvent filteringComplete = Mockito.mock(TestFilteringCompleteEvent.class);
when(filteringComplete.getTestTargets()).thenReturn(ImmutableSet.of(bartestTarget));
TestSummary testSummary = Mockito.mock(TestSummary.class);
when(testSummary.getStatus()).thenReturn(BlazeTestStatus.PASSED);
when(testSummary.getTarget()).thenReturn(bartestTarget);
if (actions >= 1) {
stateTracker.actionStarted(new ActionStartedEvent(foobuildAction, 123456789));
}
if (actions >= 2) {
stateTracker.actionStarted(new ActionStartedEvent(bazbuildAction, 123456900));
}
if (withTest) {
stateTracker.testFilteringComplete(filteringComplete);
stateTracker.testSummary(testSummary);
}
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
assertTrue(
"Only lines with at most 70 chars should be present in the output:\n" + output,
longestLine(output) <= 70);
if (actions >= 1) {
assertTrue(
"Running action 'foobuild' should be mentioned in output:\n" + output,
output.contains("foobuild"));
}
if (actions >= 2) {
assertTrue(
"Running action 'bazbuild' should be mentioned in output:\n" + output,
output.contains("bazbuild"));
}
if (withTest) {
assertTrue(
"Passed test ':bartest' should be mentioned in output:\n" + output,
output.contains(":bartest"));
}
}
@Test
public void testOutputLength() throws Exception {
for (int i = 0; i < 3; i++) {
doTestOutputLength(true, i);
doTestOutputLength(false, i);
}
}
@Test
public void testAggregation() throws Exception {
// Assert that actions for the same test are aggregated so that an action afterwards
// is still shown.
ManualClock clock = new ManualClock();
clock.advanceMillis(TimeUnit.SECONDS.toMillis(1234));
ExperimentalStateTracker stateTracker = new ExperimentalStateTracker(clock, 80);
Label labelFooTest = Label.parseAbsolute("//foo/bar:footest");
ConfiguredTarget targetFooTest = Mockito.mock(ConfiguredTarget.class);
when(targetFooTest.getLabel()).thenReturn(labelFooTest);
ActionOwner fooOwner =
ActionOwner.create(labelFooTest, null, null, null, null, null, "abcdef", null);
Label labelBarTest = Label.parseAbsolute("//baz:bartest");
ConfiguredTarget targetBarTest = Mockito.mock(ConfiguredTarget.class);
when(targetBarTest.getLabel()).thenReturn(labelBarTest);
TestFilteringCompleteEvent filteringComplete = Mockito.mock(TestFilteringCompleteEvent.class);
when(filteringComplete.getTestTargets())
.thenReturn(ImmutableSet.of(targetFooTest, targetBarTest));
ActionOwner barOwner =
ActionOwner.create(labelBarTest, null, null, null, null, null, "fedcba", null);
stateTracker.testFilteringComplete(filteringComplete);
// First produce 10 actions for footest...
for (int i = 0; i < 10; i++) {
clock.advanceMillis(TimeUnit.SECONDS.toMillis(1));
Action action = mockAction("Testing foo, shard " + i, "testlog_foo_" + i);
when(action.getOwner()).thenReturn(fooOwner);
stateTracker.actionStarted(new ActionStartedEvent(action, clock.nanoTime()));
}
// ...then produce 10 actions for bartest...
for (int i = 0; i < 10; i++) {
clock.advanceMillis(TimeUnit.SECONDS.toMillis(1));
Action action = mockAction("Testing bar, shard " + i, "testlog_bar_" + i);
when(action.getOwner()).thenReturn(barOwner);
stateTracker.actionStarted(new ActionStartedEvent(action, clock.nanoTime()));
}
// ...and finally a completely unrelated action
clock.advanceMillis(TimeUnit.SECONDS.toMillis(1));
stateTracker.actionStarted(
new ActionStartedEvent(mockAction("Other action", "other/action"), clock.nanoTime()));
clock.advanceMillis(TimeUnit.SECONDS.toMillis(1));
LoggingTerminalWriter terminalWriter = new LoggingTerminalWriter(/*discardHighlight=*/ true);
stateTracker.writeProgressBar(terminalWriter);
String output = terminalWriter.getTranscript();
assertTrue(
"Progress bar should contain ':footest', but was:\n" + output, output.contains(":footest"));
assertTrue(
"Progress bar should contain ':bartest', but was:\n" + output, output.contains(":bartest"));
assertTrue(
"Progress bar should contain 'Other action', but was:\n" + output,
output.contains("Other action"));
}
@Test
public void testSuffix() throws Exception {
assertEquals("bar", ExperimentalStateTracker.suffix("foobar", 3));
assertEquals("", ExperimentalStateTracker.suffix("foo", -2));
assertEquals("foobar", ExperimentalStateTracker.suffix("foobar", 200));
}
}