Lyrics parsing failure

[ofekd]

There's an error parsing one of Fountain's sample files:

125 |                 text = text.trim();
126 |                 if (rules_1.rules.parenthetical.test(text)) {
127 |                     return [...p, new ParentheticalToken(text)];
128 |                 }
129 |                 if (rules_1.rules.lyrics.test(text)) {
130 |                     if (previousToken.type === 'lyrics') {
                              ^
TypeError: undefined is not an object (evaluating 'previousToken.type')
Please submit an issue to https://github.com/jonnygreenwald/fountain-js/issues
      at <anonymous> (node_modules/fountain-js/dist/token.js:130:25)
      at reduce (1:11)
      at new DialogueBlock (node_modules/fountain-js/dist/token.js:116:34)
      at <anonymous> (node_modules/fountain-js/dist/lexer.js:85:39)
      at reduce (1:11)
      at tokenizeScript (node_modules/fountain-js/dist/lexer.js:63:36)
      at tokenize (node_modules/fountain-js/dist/lexer.js:35:36)
      at parse (node_modules/fountain-js/dist/fountain.js:15:67)

Here's the file:

https://github.com/nyousefi/Fountain/blob/c09b65e9d4bf6cb1c672501f793b9b3f2becd452/FountainTests/ForcedElements.fountain

I believe a simple null check at that if branch will fallback to correct behavior, but am not familiar enough with the code base to be sure that that is the case