yoastseo/build/languageProcessing/languages/cs/helpers/internal/stem.js

Yoast client-side content analysis

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = stem;
/**
 * Copyright (c) 2005, Jacques Savoy
 * Copyright (c) 2013, Jakub Dundalek.
 * Authored by Ljiljana Dolamic from the University of Neuchatel.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are permitted provided that
 * the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS AS IS AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
 */

/**
 * Takes care of palatalisation.
 *
 * @param {string} word             The word to stem.
 * @param {Object} morphologyData   The Czech morphology data.
 *
 * @returns {string}                The non-palatalised word or the original word if no such suffix is found.
 */
const palatalise = function (word, morphologyData) {
  const palataliseSuffixes = morphologyData.externalStemmer.palataliseSuffixes;
  const len = word.length;
  if (word.substring(len - 2, len) === palataliseSuffixes.palataliseSuffixCi || word.substring(len - 2, len) === palataliseSuffixes.palataliseSuffixCe || word.substring(len - 2, len) === palataliseSuffixes.palataliseSuffixCiCaron || word.substring(len - 2, len) === palataliseSuffixes.palataliseSuffixCeCaron) {
    return word.replace(word.substring(len - 2, len), palataliseSuffixes.palataliseSuffixK);
  }
  if (word.substring(len - 2, len) === palataliseSuffixes.palataliseSuffixZi || word.substring(len - 2, len) === palataliseSuffixes.palataliseSuffixZe || word.substring(len - 2, len) === palataliseSuffixes.palataliseSuffixZiCaron || word.substring(len - 2, len) === palataliseSuffixes.palataliseSuffixZeCaron) {
    return word.replace(word.substring(len - 2, len), palataliseSuffixes.palataliseSuffixH);
  }
  if (word.substring(len - 3, len) === palataliseSuffixes.palataliseSuffixCte || word.substring(len - 3, len) === palataliseSuffixes.palataliseSuffixCti || word.substring(len - 3, len) === palataliseSuffixes.palataliseSuffixCtiAccented) {
    return word.replace(word.substring(len - 3, len), palataliseSuffixes.palataliseSuffixCk);
  }
  if (word.substring(len - 3, len) === palataliseSuffixes.palataliseSuffixSte || word.substring(len - 3, len) === palataliseSuffixes.palataliseSuffixSti || word.substring(len - 3, len) === palataliseSuffixes.palataliseSuffixStiAccented) {
    return word.replace(word.substring(len - 3, len), palataliseSuffixes.palataliseSuffixSk);
  }
  return word.slice(0, -1);
};

/**
 * Removes derivational suffixes.
 *
 * @param {string} word             The word to stem.
 * @param {Object} morphologyData   The Czech morphology data.
 *
 * @returns {string}                The word without derivational suffixes or the original word if no such suffix is found.
 */
const removeDerivational = function (word, morphologyData) {
  const derivationalSuffixes = morphologyData.externalStemmer.derivationalSuffixes;
  const len = word.length;
  if (len > 8 && word.substring(len - 6, len) === derivationalSuffixes.derivationalSuffixObinec) {
    return word.slice(0, -6);
  }
  if (len > 7) {
    if (word.substring(len - 5, len) === derivationalSuffixes.derivationalSuffixIonar) {
      word = word.slice(0, -4);
      return palatalise(word, morphologyData);
    } else if (word.substring(len - 5, len) === derivationalSuffixes.derivationalSuffixOvisk || word.substring(len - 5, len) === derivationalSuffixes.derivationalSuffixOvstv || word.substring(len - 5, len) === derivationalSuffixes.derivationalSuffixOvist || word.substring(len - 5, len) === derivationalSuffixes.derivationalSuffixOvnik) {
      return word.slice(0, -5);
    }
  }
  if (len > 6) {
    if (word.substring(len - 4, len) === derivationalSuffixes.derivationalSuffixAsek || word.substring(len - 4, len) === derivationalSuffixes.derivationalSuffixLoun || word.substring(len - 4, len) === derivationalSuffixes.derivationalSuffixNost || word.substring(len - 4, len) === derivationalSuffixes.derivationalSuffixTeln || word.substring(len - 4, len) === derivationalSuffixes.derivationalSuffixOvec || word.substring(len - 5, len) === derivationalSuffixes.derivationalSuffixOvik || word.substring(len - 4, len) === derivationalSuffixes.derivationalSuffixOvtv || word.substring(len - 4, len) === derivationalSuffixes.derivationalSuffixOvin || word.substring(len - 4, len) === derivationalSuffixes.derivationalSuffixStin) {
      return word.slice(0, -4);
    } else if (word.substring(len - 4, len) === derivationalSuffixes.derivationalSuffixEnic || word.substring(len - 4, len) === derivationalSuffixes.derivationalSuffixInec || word.substring(len - 4, len) === derivationalSuffixes.derivationalSuffixItel) {
      word = word.slice(0, -3);
      return palatalise(word, morphologyData);
    }
  }
  if (len > 5) {
    if (word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixEnk || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixIan || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixIst || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixIsk || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixIstCaron || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixItb || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixIrn) {
      word = word.slice(0, -2);
      return palatalise(word, morphologyData);
    } else if (word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixArn || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixOch || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixOst || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixOvn || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixOun || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixOut || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixOus || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixUsk || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixKyn || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixCan || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixKar || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixNer || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixNik || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixCtv || word.substring(len - 3, len) === derivationalSuffixes.derivationalSuffixStv) {
      return word.slice(0, -3);
    }
  }
  if (len > 4) {
    if (word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixAcAccented || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixAc || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixAnAccented || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixAn || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixAr || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixAs) {
      return word.slice(0, -2);
    } else if (word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixEc || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixEn || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixEnCaron || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixEr || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixIr || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixIc || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixIn || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixInAccented || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixIt || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixIv) {
      word = word.slice(0, -1);
      return palatalise(word, morphologyData);
    } else if (word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixOb || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixOt || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixOv || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixOn || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixUl || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixYn || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixCk || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixCn || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixDl || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixNk || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixTv || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixTk || word.substring(len - 2, len) === derivationalSuffixes.derivationalSuffixVk) {
      return word.slice(0, -2);
    }
  }
  if (len > 3) {
    if (word.charAt(word.length - 1) === derivationalSuffixes.derivationalSuffixC || word.charAt(word.length - 1) === derivationalSuffixes.derivationalSuffixCCaron || word.charAt(word.length - 1) === derivationalSuffixes.derivationalSuffixK || word.charAt(word.length - 1) === derivationalSuffixes.derivationalSuffixL || word.charAt(word.length - 1) === derivationalSuffixes.derivationalSuffixN || word.charAt(word.length - 1) === derivationalSuffixes.derivationalSuffixT) {
      return word.slice(0, -1);
    }
  }
  return word;
};

/**
 * Removes augmentative suffixes.
 *
 * @param {string} word             The word to stem.
 * @param {Object} morphologyData   The Czech morphology data.
 *
 * @returns {string}                The word without augmentative suffixes or the original word if no such suffix is found.
 */
const removeAugmentative = function (word, morphologyData) {
  const augmentativeSuffixes = morphologyData.externalStemmer.augmentativeSuffixes;
  const len = word.length;
  if (len > 6 && word.substring(len - 4, len) === augmentativeSuffixes.augmentativeSuffixAjzn) {
    return word.slice(0, -4);
  }
  if (len > 5 && word.substring(len - 3, len) === augmentativeSuffixes.augmentativeSuffixIzn || word.substring(len - 3, len) === augmentativeSuffixes.augmentativeSuffixIsk) {
    word = word.slice(0, -2);
    return palatalise(word, morphologyData);
  }
  return word;
};

/**
 * Removes diminutive suffixes.
 *
 * @param {string} word             The word to stem.
 * @param {Object} morphologyData   The Czech morphology data.
 *
 * @returns {string}                The word without diminutive suffixes or the original word if no such suffix is found.
 */
const removeDiminutive = function (word, morphologyData) {
  const diminutiveSuffixes = morphologyData.externalStemmer.diminutiveSuffixes;
  const len = word.length;
  if (len > 7 && word.substring(len - 5, len) === diminutiveSuffixes.diminutiveSuffixOusek) {
    return word.slice(0, -5);
  }
  if (len > 6) {
    if (word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixEcek || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixEcekAccented || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixIcek || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixIcekAccented || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixEnek || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixEnekAccented || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixInek || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixInekAccented) {
      word = word.slice(0, -3);
      return palatalise(word, morphologyData);
    }
    if (word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixAcekAccented || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixAcek || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixOcek || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixUcek || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixAnek || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixOnek || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixUnek || word.substring(len - 4, len) === diminutiveSuffixes.diminutiveSuffixAnekAccented) {
      return word.slice(0, -4);
    }
  }
  if (len > 5) {
    if (word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixEck || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixEckAccented || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixIck || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixIckAccented || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixEnk || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixEnkAccented || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixInk || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixInkAccented) {
      word = word.slice(0, -3);
      return palatalise(word, morphologyData);
    }
    if (word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixAckAccented || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixAck || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixOck || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixUck || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixAnk || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixOnk || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixUnk) {
      return word.slice(0, -3);
    }
    if (word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixAtk || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixAnkAccented || word.substring(len - 3, len) === diminutiveSuffixes.diminutiveSuffixUsk) {
      return word.slice(0, -3);
    }
  }
  if (len > 4) {
    if (word.substring(len - 2, len) === diminutiveSuffixes.diminutiveSuffixEk || word.substring(len - 2, len) === diminutiveSuffixes.diminutiveSuffixEkAccented || word.substring(len - 2, len) === diminutiveSuffixes.diminutiveSuffixIkAccented || word.substring(len - 2, len) === diminutiveSuffixes.diminutiveSuffixIk) {
      word = word.slice(0, -1);
      return palatalise(word, morphologyData);
    }
    if (word.substring(len - 2, len) === diminutiveSuffixes.diminutiveSuffixAkAccented || word.substring(len - 2, len) === diminutiveSuffixes.diminutiveSuffixAk || word.substring(len - 2, len) === diminutiveSuffixes.diminutiveSuffixOk || word.substring(len - 2, len) === diminutiveSuffixes.diminutiveSuffixUk) {
      return word.slice(0, -1);
    }
  }
  if (len > 3 && word.substring(len - 1, len) === diminutiveSuffixes.diminutiveSuffixK) {
    return word.slice(0, -1);
  }
  return word;
};

/**
 * Removes comparative suffixes.
 *
 * @param {string} word             The word to stem.
 * @param {Object} morphologyData   The Czech morphology data.
 *
 * @returns {string}                The word without comparative suffixes or the original word if no such suffix is found.
 */
const removeComparative = function (word, morphologyData) {
  const comparativeSuffixes = morphologyData.externalStemmer.comparativeSuffixes;
  const len = word.length;
  if (len > 5 && word.substring(len - 3, len) === comparativeSuffixes.comparativeSuffixesEjs || word.substring(len - 3, len) === comparativeSuffixes.comparativeSuffixesEjsCaron) {
    word = word.slice(0, -2);
    return palatalise(word, morphologyData);
  }
  return word;
};

/**
 * Removes possessive suffixes.
 *
 * @param {string} word             The word to stem.
 * @param {Object} morphologyData   The Czech morphology data.
 *
 * @returns {string}                The word without possessive suffixes or the original word if no such suffix is found.
 */
const removePossessives = function (word, morphologyData) {
  const possessiveSuffixes = morphologyData.externalStemmer.possessiveSuffixes;
  const len = word.length;
  if (len > 5) {
    if (word.substring(len - 2, len) === possessiveSuffixes.possessiveSuffixOv) {
      return word.slice(0, -2);
    }
    if (word.substring(len - 2, len) === possessiveSuffixes.possessiveSuffixesUv) {
      return word.slice(0, -2);
    }
    if (word.substring(len - 2, len) === possessiveSuffixes.possessiveSuffixIn) {
      word = word.slice(0, -1);
      return palatalise(word, morphologyData);
    }
  }
  return word;
};

/**
 * Removes case suffixes.
 *
 * @param {string} word             The word to stem.
 * @param {Object} morphologyData   The Czech morphology data.
 *
 * @returns {string}                The word without case suffixes or the original word if no such suffix is found.
 */
const removeCase = function (word, morphologyData) {
  const caseSuffixes = morphologyData.externalStemmer.caseSuffixes;
  const len = word.length;
  if (len > 7 && word.substring(len - 5, len) === caseSuffixes.caseSuffixAtech) {
    return word.slice(0, -5);
  }
  if (len > 6) {
    if (word.substring(len - 4, len) === caseSuffixes.caseSuffixEtem) {
      word = word.slice(0, -3);
      return palatalise(word, morphologyData);
    }
    if (word.substring(len - 4, len) === caseSuffixes.caseSuffixAtum) {
      return word.slice(0, -4);
    }
  }
  if (len > 5) {
    if (word.substring(len - 3, len) === caseSuffixes.caseSuffixEch || word.substring(len - 3, len) === caseSuffixes.caseSuffixIch || word.substring(len - 3, len) === caseSuffixes.caseSuffixIchAccented || word.substring(len - 3, len) === caseSuffixes.caseSuffixEho || word.substring(len - 3, len) === caseSuffixes.caseSuffixEmiCaron || word.substring(len - 3, len) === caseSuffixes.caseSuffixEmi || word.substring(len - 3, len) === caseSuffixes.caseSuffixEmuAccented || word.substring(len - 3, len) === caseSuffixes.caseSuffixEte || word.substring(len - 3, len) === caseSuffixes.caseSuffixEti || word.substring(len - 3, len) === caseSuffixes.caseSuffixIho || word.substring(len - 3, len) === caseSuffixes.caseSuffixIhoAccented || word.substring(len - 3, len) === caseSuffixes.caseSuffixImi || word.substring(len - 3, len) === caseSuffixes.caseSuffixImu) {
      word = word.slice(0, -2);
      return palatalise(word, morphologyData);
    } else if (word.substring(len - 3, len) === caseSuffixes.caseSuffixAchAccented || word.substring(len - 3, len) === caseSuffixes.caseSuffixAta || word.substring(len - 3, len) === caseSuffixes.caseSuffixAty || word.substring(len - 3, len) === caseSuffixes.caseSuffixYch || word.substring(len - 3, len) === caseSuffixes.caseSuffixAma || word.substring(len - 3, len) === caseSuffixes.caseSuffixAmi || word.substring(len - 3, len) === caseSuffixes.caseSuffixOve || word.substring(len - 3, len) === caseSuffixes.caseSuffixOvi || word.substring(len - 3, len) === caseSuffixes.caseSuffixYmi) {
      return word.slice(0, -3);
    }
  }
  if (len > 4) {
    if (word.substring(len - 2, len) === caseSuffixes.caseSuffixEm) {
      word = word.slice(0, -1);
      return palatalise(word, morphologyData);
    } else if (word.substring(len - 2, len) === caseSuffixes.caseSuffixEs || word.substring(len - 2, len) === caseSuffixes.caseSuffixEmAccented || word.substring(len - 2, len) === caseSuffixes.caseSuffixIm) {
      word = word.slice(0, -2);
      return palatalise(word, morphologyData);
    } else if (word.substring(len - 2, len) === caseSuffixes.caseSuffixUm || word.substring(len - 2, len) === caseSuffixes.caseSuffixAt || word.substring(len - 2, len) === caseSuffixes.caseSuffixAm || word.substring(len - 2, len) === caseSuffixes.caseSuffixOs || word.substring(len - 2, len) === caseSuffixes.caseSuffixUs || word.substring(len - 2, len) === caseSuffixes.caseSuffixYm || word.substring(len - 2, len) === caseSuffixes.caseSuffixMi || word.substring(len - 2, len) === caseSuffixes.caseSuffixOu) {
      return word.slice(0, -2);
    }
  }
  if (len > 3) {
    if (word.substring(len - 1, len) === caseSuffixes.caseSuffixE || word.substring(len - 1, len) === caseSuffixes.caseSuffixI || word.substring(len - 1, len) === caseSuffixes.caseSuffixIAccented || word.substring(len - 1, len) === caseSuffixes.caseSuffixECaron) {
      return palatalise(word, morphologyData);
    } else if (word.substring(len - 1, len) === caseSuffixes.caseSuffixU || word.substring(len - 1, len) === caseSuffixes.caseSuffixY || word.substring(len - 1, len) === caseSuffixes.caseSuffixURing || word.substring(len - 1, len) === caseSuffixes.caseSuffixA || word.substring(len - 1, len) === caseSuffixes.caseSuffixO || word.substring(len - 1, len) === caseSuffixes.caseSuffixAAccented || word.substring(len - 1, len) === caseSuffixes.caseSuffixEAccented || word.substring(len - 1, len) === caseSuffixes.caseSuffixYAccented) {
      return word.slice(0, -1);
    }
  }
  return word;
};

/**
 * Checks whether a word is in the full-form exception list and if so returns the canonical stem.
 *
 * @param {string} word	            The word to be checked.
 * @param {Object} morphologyData   The Czech morphology data.
 *
 * @returns {string}                The canonical stem if word was found on the list or the original word otherwise.
 */
const checkWordInFullFormExceptions = function (word, morphologyData) {
  for (const paradigm of morphologyData.externalStemmer.exceptionStemsWithFullForms) {
    if (paradigm[1].includes(word)) {
      return paradigm[0];
    }
  }
  return word;
};

/**
 * Check whether the stem is on the exception list of stems that belong to one word. If it is, returns the canonical stem.
 *
 * @param {string}	word			The stemmed word.
 * @param {Object} morphologyData   The Czech morphology data.
 *
 * @returns {string}                The canonical stem if word was found on the list or the original word otherwise.
 */
const canonicalizeStem = function (word, morphologyData) {
  // Checks the nouns list.
  for (const paradigm of morphologyData.externalStemmer.stemsThatBelongToOneWord.nouns) {
    if (paradigm.includes(word)) {
      return paradigm[0];
    }
  }
  return word;
};

/**
 * Stems Czech words.
 *
 * @param {string} word             The word to stem.
 * @param {Object} morphologyData   The Czech morphology data.
 *
 * @returns {string}                The stemmed word.
 */
function stem(word, morphologyData) {
  word = word.toLowerCase();
  // Checks if the word is on an exception list for which all forms of a word and its stem are listed.
  word = checkWordInFullFormExceptions(word, morphologyData);
  // Removes case endings from nouns and adjectives.
  word = removeCase(word, morphologyData);
  // Removes possessive -ov- and -in- endings from names.
  word = removePossessives(word, morphologyData);
  // Removes comparative endings.
  word = removeComparative(word, morphologyData);
  // Removes diminutive endings.
  word = removeDiminutive(word, morphologyData);
  // Removes augmentatives endings.
  word = removeAugmentative(word, morphologyData);
  // Removes derivational suffixes from nouns.
  word = removeDerivational(word, morphologyData);
  // Checks whether the stem is on the exception list of stems that belong to one word.
  word = canonicalizeStem(word, morphologyData);
  return word;
}
//# sourceMappingURL=stem.js.map