Recast.print removes trailing new line

[AugustinLF]

I added a line in the middle of a file, and reprinted it, the trailing new line I had disappear. I didn't change any options, but isn't the reuseWhitespace suppose to be sufficient? Is there anything I misunderstood?

Here is the flow:

function File(filestring) {
  this.ast = recast.parse(filestring, {
    esprima: require('babel-core')
  });
}

File.prototype.print = function() {
  return recast.print(this.ast).code;
};

// Some modifications on the tree

fs.writeFile(filePath, file.print(), callback);

Nothing fancy, the print works perfectly, I got the line I wanted, but the trailing new line of my file disappeared. Any clues?

[benjamn]

Ah, options.reuseWhitespace is just for indentation whitespace (spaces and possibly tabs), though its meaning could possibly be extended its meaning to include lines as well.

In this case, I think the culprit is printStatementSequence, which tries to reuse the whitespace in between statements in a list of reprinted statements, but generally trims away any leading/trailing space before/after the first/last statements.

I think I can fix that pretty quickly (today).

Thanks for the report!

[AugustinLF]

That would be awesome, thanks a lot!