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undefined method '<<' for nil:NilClass #8

ghost opened this Issue · 28 comments

It does not seem to be working with Sinatra 1.3.2

When just requiring rack-flash it throws this error:

ERROR NoMethodError: undefined method `<<' for nil:NilClass
    /Users/david/.rvm/gems/ruby-1.9.3-p0/gems/rack-flash-0.1.2/lib/rack/flash.rb:11:in `use'
    /Users/david/.rvm/gems/ruby-1.9.3-p0/gems/sinatra-1.3.2/lib/sinatra/base.rb:1339:in `setup_default_middleware'
    /Users/david/.rvm/gems/ruby-1.9.3-p0/gems/sinatra-1.3.2/lib/sinatra/base.rb:1327:in `build'
    /Users/david/.rvm/gems/ruby-1.9.3-p0/gems/sinatra-1.3.2/lib/sinatra/base.rb:1321:in `new'
    /Users/david/.rvm/gems/ruby-1.9.3-p0/gems/sinatra-1.3.2/lib/sinatra/base.rb:1311:in `prototype'
    /Users/david/.rvm/gems/ruby-1.9.3-p0/gems/sinatra-1.3.2/lib/sinatra/base.rb:1334:in `block in call'
    /Users/david/.rvm/gems/ruby-1.9.3-p0/gems/sinatra-1.3.2/lib/sinatra/base.rb:1416:in `synchronize'
    /Users/david/.rvm/gems/ruby-1.9.3-p0/gems/sinatra-1.3.2/lib/sinatra/base.rb:1334:in `call'
    /Users/david/.rvm/gems/ruby-1.9.3-p0/gems/rack-1.4.0/lib/rack/handler/webrick.rb:59:in `service'
    /Users/david/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/webrick/httpserver.rb:138:in `service'
    /Users/david/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/webrick/httpserver.rb:94:in `run'
    /Users/david/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/webrick/server.rb:191:in `block in start_thread'

Also happening to me.


I'm getting this too


It works with Sinatra 1.3.2, but you must downgrade Rack to v1.3.6.


throwing a "me too" on this, the workaround @tonkla posted works for me, rack was on 1.4.0, went down to 1.3.6 and the error goes away.


So, is this a Rack-flash issue, or a Rack issue?


Rack 1.4.0 was changed the infrastructure, so Rack-flash will follow that steps.


Also confirmed here


Confirmed this as an issue on my end as well. This is occurring on Heroku with the bamboo-mri-1.9.2 stack. Text of error:

!! Unexpected error while processing request: undefined method `<<' for nil:NilClass

Confirmed with these:
Using bundler (1.0.21)
Using rack (1.3.5)
Using rack-flash (0.1.2)
Using sinatra (1.3.1)
ruby 1.9.3p0


Same here, any workaround in the meantime?


I've the same problem, downgrading rack to 1.3.6 in the meantime, Gemfile:
gem "rack", "<= 1.3.6"

Using rack (1.3.6) 
Using rack-flash (0.1.2) 
Using sinatra (1.3.2) 

alternative: sinatra-flash


Yeah, that's what I've moved to at this point.


I've had a look and it seems to be caused by some dead code. Removing it seemed to fix it for me, and I'm not sure what it was ever supposed to do because it was monkey patching Rack::Builder!!

The tests don't run because it requires Sinatra < 1.0 (again, !!!!) Once I've had a look at the tests I'll put in a pull request, but in the meantime folks, take a look at the fork linked above.


Can someone pull Chris Causer's fix?


Hey guys, decided to go ahead and push a new gem that includes @ChrisCauser 's fixes, you can use it with:

gem 'rack-flash3'



@treeder, does it really need to require Ruby 1.9?


@viking probably not, copied that rakefile from another gem. Removed and pushed new version just now.


Awesome, thanks


+1, same error here. Thanks to @treeder for rack-flash3, I'm using that now instead.


+1, Thanks @treeder , rack-flash3 works!


np. ;)


rack-flash3 works great! thanks! @nakajima should merge in the fix!


rack-flash3 is the great fix (had to gem uninstall rack-flash to make her work) Thank! Merge it!


Thanks @malachaifrazier. That fix may have been obvious to some but it saved me a brief headache at the very least.


This projects seems dead, not able to merge pull request for 8 months.

@tlianza tlianza referenced this issue in sinatra/

Rack:Flash #56


I'm trying to use rack-flash3 with sinatra-authentication, unfortunately I cannot get the latter gem to recognize it. The only way I can get the sinatra-authentication gem to work is by using the Rack 1.3.6 gem, 1.4.1 does not fix the issue.

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