CandidateAssertions.java

package com.github.liblevenshtein.assertion;

import org.assertj.core.api.AbstractAssert;

import com.github.liblevenshtein.distance.IDistance;
import com.github.liblevenshtein.transducer.Candidate;

/**
 * AssertJ-style assertions for {@link Candidate}s.
 */
public class CandidateAssertions
    extends AbstractAssert<CandidateAssertions, Candidate> {

  /**
   * Constructs a new {@link Candidate} to assert-against.
   * @param actual {@link Candidate} to assert-against.
   */
  public CandidateAssertions(final Candidate actual) {
    super(actual, CandidateAssertions.class);
  }

  /**
   * Builds a new {@link Candidate} to assert-against.
   * @param actual {@link Candidate} to assert-against.
   * @return A new {@link Candidate} to assert-against.
   */
  public static CandidateAssertions assertThat(final Candidate actual) {
    return new CandidateAssertions(actual);
  }

  /**
   * Asserts that the actual distance is the expected distance from the query
   * term, as specified by the distance function.
   * @param distance Distance function for validation.
   * @param queryTerm Term whose distance from the spelling candidate is to be
   *   determined.
   * @return This {@link CandidateAssertions} for fluency.
   * @throws AssertionError When the actual distance differs from what's
   *   expected.
   */
  public CandidateAssertions hasDistance(
      final IDistance<String> distance,
      final String queryTerm) {

    isNotNull();

    final int expectedDistance = distance.between(queryTerm, actual.term());

    if (expectedDistance != actual.distance()) {
      failWithMessage(
        "Expected d(%s, %s) = [%d], but was [%d]",
        queryTerm, actual.term(), expectedDistance, actual.distance());
    }

    return this;
  }
}