/* eslint-disable */ /*! * lunr.stemmer * Copyright (C) @YEAR Oliver Nightingale * Includes code from - http://tartarus.org/~martin/PorterStemmer/js.txt */ /** * lunr.stemmer is an english language stemmer, this is a JavaScript * implementation of the PorterStemmer taken from http://tartarus.org/~martin * * @static * @implements {lunr.PipelineFunction} * @param {lunr.Token} token - The string to stem * @returns {lunr.Token} * @see {@link lunr.Pipeline} * @function */ lunr.stemmer = (function(){ var step2list = { "ational" : "ate", "tional" : "tion", "enci" : "ence", "anci" : "ance", "izer" : "ize", "bli" : "ble", "alli" : "al", "entli" : "ent", "eli" : "e", "ousli" : "ous", "ization" : "ize", "ation" : "ate", "ator" : "ate", "alism" : "al", "iveness" : "ive", "fulness" : "ful", "ousness" : "ous", "aliti" : "al", "iviti" : "ive", "biliti" : "ble", "logi" : "log" }, step3list = { "icate" : "ic", "ative" : "", "alize" : "al", "iciti" : "ic", "ical" : "ic", "ful" : "", "ness" : "" }, c = "[^aeiou]", // consonant v = "[aeiouy]", // vowel C = c + "[^aeiouy]*", // consonant sequence V = v + "[aeiou]*", // vowel sequence mgr0 = "^(" + C + ")?" + V + C, // [C]VC... is m>0 meq1 = "^(" + C + ")?" + V + C + "(" + V + ")?$", // [C]VC[V] is m=1 mgr1 = "^(" + C + ")?" + V + C + V + C, // [C]VCVC... is m>1 s_v = "^(" + C + ")?" + v; // vowel in stem var re_mgr0 = new RegExp(mgr0); var re_mgr1 = new RegExp(mgr1); var re_meq1 = new RegExp(meq1); var re_s_v = new RegExp(s_v); var re_1a = /^(.+?)(ss|i)es$/; var re2_1a = /^(.+?)([^s])s$/; var re_1b = /^(.+?)eed$/; var re2_1b = /^(.+?)(ed|ing)$/; var re_1b_2 = /.$/; var re2_1b_2 = /(at|bl|iz)$/; var re3_1b_2 = new RegExp("([^aeiouylsz])\\1$"); var re4_1b_2 = new RegExp("^" + C + v + "[^aeiouwxy]$"); var re_1c = /^(.+?[^aeiou])y$/; var re_2 = /^(.+?)(ational|tional|enci|anci|izer|bli|alli|entli|eli|ousli|ization|ation|ator|alism|iveness|fulness|ousness|aliti|iviti|biliti|logi)$/; var re_3 = /^(.+?)(icate|ative|alize|iciti|ical|ful|ness)$/; var re_4 = /^(.+?)(al|ance|ence|er|ic|able|ible|ant|ement|ment|ent|ou|ism|ate|iti|ous|ive|ize)$/; var re2_4 = /^(.+?)(s|t)(ion)$/; var re_5 = /^(.+?)e$/; var re_5_1 = /ll$/; var re3_5 = new RegExp("^" + C + v + "[^aeiouwxy]$"); var porterStemmer = function porterStemmer(w) { var stem, suffix, firstch, re, re2, re3, re4; if (w.length < 3) { return w; } firstch = w.substr(0,1); if (firstch == "y") { w = firstch.toUpperCase() + w.substr(1); } // Step 1a re = re_1a re2 = re2_1a; if (re.test(w)) { w = w.replace(re,"$1$2"); } else if (re2.test(w)) { w = w.replace(re2,"$1$2"); } // Step 1b re = re_1b; re2 = re2_1b; if (re.test(w)) { var fp = re.exec(w); re = re_mgr0; if (re.test(fp[1])) { re = re_1b_2; w = w.replace(re,""); } } else if (re2.test(w)) { var fp = re2.exec(w); stem = fp[1]; re2 = re_s_v; if (re2.test(stem)) { w = stem; re2 = re2_1b_2; re3 = re3_1b_2; re4 = re4_1b_2; if (re2.test(w)) { w = w + "e"; } else if (re3.test(w)) { re = re_1b_2; w = w.replace(re,""); } else if (re4.test(w)) { w = w + "e"; } } } // Step 1c - replace suffix y or Y by i if preceded by a non-vowel which is not the first letter of the word (so cry -> cri, by -> by, say -> say) re = re_1c; if (re.test(w)) { var fp = re.exec(w); stem = fp[1]; w = stem + "i"; } // Step 2 re = re_2; if (re.test(w)) { var fp = re.exec(w); stem = fp[1]; suffix = fp[2]; re = re_mgr0; if (re.test(stem)) { w = stem + step2list[suffix]; } } // Step 3 re = re_3; if (re.test(w)) { var fp = re.exec(w); stem = fp[1]; suffix = fp[2]; re = re_mgr0; if (re.test(stem)) { w = stem + step3list[suffix]; } } // Step 4 re = re_4; re2 = re2_4; if (re.test(w)) { var fp = re.exec(w); stem = fp[1]; re = re_mgr1; if (re.test(stem)) { w = stem; } } else if (re2.test(w)) { var fp = re2.exec(w); stem = fp[1] + fp[2]; re2 = re_mgr1; if (re2.test(stem)) { w = stem; } } // Step 5 re = re_5; if (re.test(w)) { var fp = re.exec(w); stem = fp[1]; re = re_mgr1; re2 = re_meq1; re3 = re3_5; if (re.test(stem) || (re2.test(stem) && !(re3.test(stem)))) { w = stem; } } re = re_5_1; re2 = re_mgr1; if (re.test(w) && re2.test(w)) { re = re_1b_2; w = w.replace(re,""); } // and turn initial Y back to y if (firstch == "y") { w = firstch.toLowerCase() + w.substr(1); } return w; }; return function (token) { return token.update(porterStemmer); } })(); lunr.Pipeline.registerFunction(lunr.stemmer, 'stemmer')