Wierd NomethodError

rubyonrails-talk
#1

Hello,

I have my source here : https://github.com/roelof1967/tamara

When I do cucumber I get this error message :
Then he should see “Welcome, Aslak” # features/step_definitions/login_steps.rb:27
undefined method messages' for nil:NilClass (NoMethodError) ./features/step_definitions/login_steps.rb:28:in /^he should see “(.*?)”$/’
features/login.feature:6:in `Then he should see “Welcome, Aslak”’

Which I find wierd because I have a method messages made in my class Output.

Roelof

#2

You have the messages method, but the error is saying that the object
you are calling it on is nil. So on the line that is calling
something.messages then the something is nil. You have to work out
why it is nil.

Colin

#3

The only thing I can think of is that output is not created.

But that cannot be the reason because there is a function create which contains Ouput.new which is the same as Output.create.

Roelof

#4

From: clanlaw@googlemail.com
Date: Sun, 4 Nov 2012 09:23:09 +0000
Subject: Re: [Rails] Wierd NomethodError
To: rwobben@hotmail.com

Please don't top post, it makes it difficult to follow the thread.
Insert your replies at appropriate points in previous message.
Thanks.

> The only thing I can think of is that output is not created.
> But that cannot be the reason because there is a function create which
> contains Ouput.new which is the same as Output.create.

It might help if you were to show us the bit of code generating the
error. We are not telepathic. At least I am not. Look carefully at
the error message to find the relevant code.

The error message can be found here : https://gist.github.com/4008123
And the relevant code can be found here :
https://github.com/roelof1967/tamara/blob/master/features/step_definitions/login_steps.rb

That is a different error message to the one you originally posted.

What is the line
messages << message
supposed to do. What is the variable messages?

Have a look at the Rails Guide on debugging, it will show you
techniques that you can use to debug your code and work out what is
going wrong.

Colin

#5

From: cla...@googlemail.com

Date: Sun, 4 Nov 2012 09:23:09 +0000

Subject: Re: [Rails] Wierd NomethodError

To: rwo...@hotmail.com

Please don’t top post, it makes it difficult to follow the thread.

Insert your replies at appropriate points in previous message.

Thanks.

The only thing I can think of is that output is not created.

But that cannot be the reason because there is a function create which

contains Ouput.new which is the same as Output.create.

It might help if you were to show us the bit of code generating the

error. We are not telepathic. At least I am not. Look carefully at

the error message to find the relevant code.

The error message can be found here : https://gist.github.com/4008123

And the relevant code can be found here :

https://github.com/roelof1967/tamara/blob/master/features/step_definitions/login_steps.rb

That is a different error message to the one you originally posted.

What is the line

messages << message

supposed to do. What is the variable messages?

The variable messages is a array containing the all the messages.

The variable message does contain the message.
I took this part of the Rspec book.

Have a look at the Rails Guide on debugging, it will show you

techniques that you can use to debug your code and work out what is

going wrong.

I will look into it and hope I can find a solution to this problem.

#6

I have no idea what you are saying now. Is this a different problem?
If so then again post the error message and the relevant code. Just
put the code inline here unless it is long, it is easier to comment
here than if you have put it somewhere else. You only need to post
the relevant 10 or 20 lines.

Colin

PS Just send it to the list, no need to copy me.

#7

No I try to answer where message is coming from.

Message is as I understand from the step-definition and should include the text “Welcome asLak”

Roelof

#8

Sorry, you still have not explained the problem. Explain what is
happening, what should be happening, and show us the code that should
do what you expect. Without that information we can do nothing.

You are still sending a copy to me by the way, which is undesirable.

Colin

#9

…

Message come from here.

Then he should see “Welcome, Aslak”

Then /^he should see “(.*?)”$/ do |message|

@output.messages.should include (message)

end

I have no idea what you are saying now. Is this a different problem?

If so then again post the error message and the relevant code. Just

put the code inline here unless it is long, it is easier to comment

here than if you have put it somewhere else. You only need to post

the relevant 10 or 20 lines.

Colin

No I try to answer where message is coming from.

Message is as I understand from the step-definition and should include the

text “Welcome asLak”

Sorry, you still have not explained the problem. Explain what is

happening,

What happen is that I see the error message.

what should be happening

What schould be happen is that the message “Welcome Aslak” is being seen as the user Aslak is loggin in succesfull.

, and show us the code that should

do what you expect.

I will give you the cucumber code.

Scenario: log in as existing user

Given a user “Aslak@tamarawobben.nl” exists

When he logs in

Then he should see “Welcome, Aslak”

step-definition part :

class Output

def messages

@messages ||= []

end

def puts(message)

messages << message

end

def output

@output ||= Output.new

end

end

Then /^he should see “(.*?)”$/ do |message|

@output.messages.should include (message)

end

Roelof

#10

>
>>
>> > ...
>> > Message come from here.
>> >
>> > Then he should see "Welcome, Aslak"
>> >
>> > Then /^he should see "(.*?)"$/ do |message|
>> > @output.messages.should include (message)
>> > end
>>
>> I have no idea what you are saying now. Is this a different problem?
>> If so then again post the error message and the relevant code. Just
>> put the code inline here unless it is long, it is easier to comment
>> here than if you have put it somewhere else. You only need to post
>> the relevant 10 or 20 lines.
>>
>> Colin
>
>
> No I try to answer where message is coming from.
> Message is as I understand from the step-definition and should include
> the
> text "Welcome asLak"

Sorry, you still have not explained the problem. Explain what is
happening,

What happen is that I see the error message.

what should be happening

What schould be happen is that the message "Welcome Aslak" is being seen as
the user Aslak is loggin in succesfull.

, and show us the code that should
do what you expect.

I will give you the cucumber code.

Scenario: log in as existing user
Given a user "Aslak@tamarawobben.nl" exists
When he logs in
Then he should see "Welcome, Aslak"

step-definition part :

class Output
def messages
@messages ||= []
end
def puts(message)
messages << message

It is difficult to help if you don't read and try to understand the
attempts to help you. As I have said before you have not initialised
the local variable messages. You have initialised the class instance
variable @messages, but that is not the same variable.

In addition I have asked twice if not three times that you do not send
me personally a copy of your emails. Just send it to the list please,
I do not need two copies.

Colin

#11

I don’t see where you’re initializing @output anywhere in that file - it’s going to be hard to call methods on an uninitialized instance variable…

–Matt Jones

#12

Hello,

Im initializing that file here :

def output
@output ||= Output.new

end

in the class Output.

Roelof

#13

when you call @output.messages.should include (message)

@output is nil

call (@output ||= Output.new).messages.should include (message)

#14

when you call @output.messages.should include (message)

@output is nil

call (@output ||= Output.new).messages.should include (message)

That worked but can you explain what this does ?

Roelof

#15

get instance variable @output, and when its nil assigns an object Output.new

#16

This method doesn’t make any sense - you need to create an Output instance to call it on, then it creates an Output instance. I’d suggest you review a good Ruby reference to sort out your understanding of how objects work.

More to the point, what is the Output class supposed to DO? Your cucumber step seemed to be expecting that messages would be sent to an Output object, but I don’t see any indication of how that was supposed to happen…

–Matt Jones

–Matt Jones

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