Bug #11485
Updated by nobu (Nobuyoshi Nakada) almost 5 years ago
This seems to be a regression in the Ripper parser where the `on_ignored_nl` event is passed a nil value for the token parameter in the event when a syntax error occurs. I'm not entirely sure of the details, but this is the most minimal reproduction example I could produce: ~~~ruby ~~~ require 'ripper' class Parser < Ripper def on_ignored_nl(*args) p args end def on_parse_error(msg) $stderr.puts "ERROR! #{msg}" end end Parser.new(DATA, 'stdin').parse __END__ something # comment ... ~~~ Note the "..." which causes the parse error, but the comment on the line before causes the ignored_nl event to get called with `nil` as the argument. I'm not sure if it's specific to the `...` token or if there are other ways to trigger this parse error. I tried with other invalid syntaxes and could not reproduce with those. Running the above produces the following output (in 2.0.0p481 and 2.3.0-dev respective): ~~~ ~$ ruby -v ruby 2.0.0p481 (2014-05-08 revision 45883) [universal.x86_64-darwin14] ~$ ruby ripper-bug-2.2.0.rb ERROR! syntax error, unexpected ..., expecting end-of-input ~$ ruby -v ruby 2.3.0dev (2015-08-24 trunk 51672) [x86_64-darwin14] ~$ ruby ripper-bug-2.2.0.rb [nil] ERROR! syntax error, unexpected ..., expecting end-of-input ~~~ I would not expect the token parameter to ever be `nil`, since a token event should always have a token to pass in if it is triggered. Note that this event typically produces a "\n" token value (and still does in normal cases). The expectation should be to either provide a valid token or not trigger the event at all. (This behavior is present in 2.2.0p95 as well.)