jscpd/lib/strategy.js

Copy/paste detector for programming code, support JavaScript, CoffeeScript, PHP, Ruby, Python, Less, Go, Java, Yaml, C#, C++, C languages

// Generated by CoffeeScript 1.10.0
(function() {
  var Clone, Storage, Strategy, TokenizerFactory, crypto, shjs;

  shjs = require('shelljs');

  TokenizerFactory = require('./tokenizer/TokenizerFactory');

  crypto = require('crypto');

  Storage = require('./storage/StorageMemory');

  Clone = require('./clone').Clone;

  Strategy = (function() {
    function Strategy(options) {
      this.options = options;
      this.languages = options.languages;
      this.storage = new Storage();
    }

    Strategy.prototype.detect = function(map, file, minLines, minTokens) {
      var code, currentMap, firstHash, firstLine, firstToken, hash, isClone, language, lastToken, lines, mapFrame, ref, tokenNumber, tokenizer, tokensPositions;
      this.minLines = minLines;
      this.minTokens = minTokens;
      tokenizer = TokenizerFactory.prototype.makeTokenizer(file, this.languages);
      if (!tokenizer) {
        return false;
      }
      language = tokenizer.getType();
      if (shjs.test('-f', file)) {
        code = shjs.cat(file);
      } else {
        return false;
      }
      lines = code.split('\n');
      map.numberOfLines = map.numberOfLines + lines.length;
      tokenizer.skipComments = this.options['skip-comments'];
      ref = tokenizer.tokenize(code).generateMap(), tokensPositions = ref.tokensPositions, currentMap = ref.currentMap;
      firstLine = 0;
      tokenNumber = 0;
      isClone = false;
      while (tokenNumber <= tokensPositions.length - this.minTokens) {
        mapFrame = currentMap.substring(tokenNumber * 33, tokenNumber * 33 + this.minTokens * 33);
        hash = crypto.createHash('md5').update(mapFrame).digest('hex');
        if (this.storage.hasHash(hash, language)) {
          isClone = true;
          if (firstLine === 0) {
            firstLine = tokensPositions[tokenNumber];
            firstHash = hash;
            firstToken = tokenNumber;
          }
        } else {
          if (isClone) {
            lastToken = tokenNumber + this.minTokens - 2;
            this.addClone(map, file, firstHash, firstToken, lastToken, firstLine, tokensPositions[lastToken], language);
            firstLine = 0;
            isClone = false;
          }
          this.storage.addHash(hash, file, tokensPositions[tokenNumber], language);
        }
        tokenNumber = tokenNumber + 1;
      }
      if (isClone) {
        lastToken = tokenNumber + this.minTokens - 2;
        this.addClone(map, file, firstHash, firstToken, lastToken, firstLine, tokensPositions[lastToken], language);
        return isClone = false;
      }
    };

    Strategy.prototype.addClone = function(map, file, hash, firstToken, lastToken, firstLine, lastLine, language) {
      var fileA, firstLineA, hashInfo, numLines;
      hashInfo = this.storage.getHash(hash, language);
      fileA = hashInfo.file;
      firstLineA = hashInfo.line;
      numLines = lastLine + 1 - firstLine;
      if (numLines >= this.minLines && (fileA !== file || firstLineA !== firstLine)) {
        return map.addClone(new Clone(fileA, file, firstLineA, firstLine, numLines, lastToken - firstToken + 1));
      }
    };

    return Strategy;

  })();

  exports.Strategy = Strategy;

}).call(this);