### Testing

The project uses JUnit 4 with embedded OpenSearch for integration testing:

```bash
# Run all tests
mvn test

# Run specific test class
mvn test -Dtest=SuggesterTest

# Run with verbose output
mvn surefire:test -Dmaven.surefire.debug=true
```

### Running Tests with Coverage

```bash
mvn clean jacoco:prepare-agent test jacoco:report
```

name: Upgrade old version tests

on:
  pull_request:
    branches:
      - master

# This ensures that previous jobs for the PR are canceled when the PR is
# updated.
concurrency:
  group: ${{ github.workflow }}-${{ github.head_ref }}
  cancel-in-progress: true

permissions:
  contents: read

jobs:
  build:
    name: Go ${{ matrix.go-version }} on ${{ matrix.os }}
    runs-on: ${{ matrix.os }}
    strategy:

package com.google.common.collect.testing.google;

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests unconditional {@code setCount()} operations on a multiset. Can't
 * be invoked directly; please see {@link MultisetTestSuiteBuilder}.
 *
 * @author Chris Povirk
 */
@GwtCompatible

/**
 * A generic JUnit test which tests {@link Map#putIfAbsent}. Can't be invoked directly; please see
 * {@link com.google.common.collect.testing.MapTestSuiteBuilder}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.

import com.google.common.collect.testing.features.CollectionFeature;
import com.google.common.collect.testing.features.CollectionSize;
import org.junit.Ignore;

/**
 * A generic JUnit test which tests creation (typically through a constructor or static factory
 * method) of a list. Can't be invoked directly; please see {@link
 * com.google.common.collect.testing.ListTestSuiteBuilder}.
 *
 * @author Chris Povirk
 */

            final Map<String, Set<Class<?>>> suffixToBaseClass;
            if (classes.isEmpty()) {
                // Don't load base classes if we don't have any tests.
                // This allows defaults to be configured for projects that don't have any tests
                //
                suffixToBaseClass = Collections.emptyMap();
            } else {
                suffixToBaseClass = naming.stream()

Available JDKs on your machine are automatically detected and wired for the various compile and test tasks.
Some tests require multiple JDKs to be installed on your computer, be aware of this if you make changes related to anything toolchains related.

import java.util.List;
import java.util.Set;
import org.junit.Ignore;

/**
 * Tests for {@link SetMultimap#replaceValues}.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")
// @Ignore affects the Android test runner, which respects JUnit 4 annotations on JUnit 3 tests.
@SuppressWarnings("JUnit4ClassUsedInJUnit3")

import java.util.List;
import junit.framework.AssertionFailedError;
import org.jspecify.annotations.NullMarked;

/**
 * Implementation helper for {@link EqualsTester} and {@link EquivalenceTester} that tests for
 * equivalence classes.
 *
 * @author Gregory Kick
 */
@GwtCompatible
@NullMarked
final class RelationshipTester<T> {
  interface ItemReporter {
    String reportItem(Item<?> item);
  }

  /**

Before code can be accepted all contributors must complete our
[Individual Contributor License Agreement (CLA)][cla].


Code Contributions
------------------

Get working code on a personal branch with tests passing before you submit a PR:

```
./gradlew clean check
```

Please make every effort to follow existing conventions and style in order to keep the code as
readable as possible.