_shouldProcessFile(path) {
    // Get file's extension:
    var syntax = this._extractSyntax(path);

    // Check if syntax is supported. If not, ignore the file:
    if (!this.supportedSyntaxes.has(syntax))
      return false;

    return this._shouldProcess(path);
  }
Checks if specified path is not present in `exclude` list and it has one of
acceptable syntaxes.

@param {String} path
@returns {Boolean} False if the path either has unacceptable extension or
is present in `exclude` list. True if everything is ok.