LanguageModelTestBase.java

/*
 * Carrot2 project.
 *
 * Copyright (C) 2002-2016, Dawid Weiss, Stanisław Osiński.
 * All rights reserved.
 *
 * Refer to the full license file "carrot2.LICENSE"
 * in the root folder of the repository checkout or at:
 * http://www.carrot2.org/carrot2.LICENSE
 */

package org.carrot2.text.linguistic;

import org.carrot2.core.LanguageCode;
import org.carrot2.text.util.MutableCharArray;
import org.carrot2.util.tests.CarrotTestCase;
import org.junit.Before;
import org.junit.Test;

import static org.junit.Assert.*;

/**
 * Superclass for testing {@link LanguageModel}s.
 */
public abstract class LanguageModelTestBase extends CarrotTestCase
{
    /**
     * 
     */
    protected LanguageModel languageModel;

    /**
     * @return Returns language code for this test.
     */
    protected abstract LanguageCode getLanguageCode();

    /**
     * 
     */
    @Before
    public void setupLanguage()
    {
        this.languageModel = LanguageModel.create(getLanguageCode(),
            new DefaultStemmerFactory(), new DefaultTokenizerFactory(),
            new DefaultLexicalDataFactory());
    }

    /**
     * 
     */
    @Test
    public void testStemmerAvailable()
    {
        assertNotNull(languageModel.getStemmer());
        assertThat(languageModel.getStemmer().getClass()).as("Stemmer class for: " + languageModel.getLanguageCode())
            .isNotEqualTo(IdentityStemmer.class);
    }

    /**
     * 
     */
    @Test
    public void testLanguageCode()
    {
        assertEquals(getLanguageCode(), languageModel.getLanguageCode());
    }

    /**
     * 
     */
    @Test
    public void testStemming()
    {
        final String [][] testData = getStemmingTestData();
        final IStemmer stemmer = languageModel.getStemmer();

        for (String [] pair : testData)
        {
            CharSequence stemmed = stemmer.stem(pair[0]);
            assertEquals("Stemming difference: " + pair[0] + " should become " + pair[1]
                + " but was transformed into " + stemmed, pair[1], stemmed == null ? null
                : stemmed.toString());
        }
    }

    /**
     * 
     */
    @Test
    public void testCommonWords()
    {
        final String [] testData = getCommonWordsTestData();
        for (String word : testData)
        {
            assertTrue(languageModel.getLexicalData().isCommonWord(
                new MutableCharArray(word)));
        }
    }

    /**
     * Override and provide word pairs for {@link LanguageModel#getStemmer()} tests.
     * Sample data should follow this format:
     * 
     * <pre>
     * return new String [] []
     * {
     *     {
     *         "inflected", "base"
     *     },
     *     {
     *         "inflected", "base"
     *     },
     * };
     * </pre>
     */
    protected String [][] getStemmingTestData()
    {
        return new String [] [] {
        /* Empty by default. */
        };
    }

    /**
     * Override and provide words for testing against
     * {@link ILexicalData#isCommonWord(MutableCharArray)}).
     */
    protected String [] getCommonWordsTestData()
    {
        return new String [] {
        /* Empty by default. */
        };
    }

}