Forum: RSpec assert_select - to do negative tests - need help with syntax please :)

Hi all,

  I am trying to figure out how to use assert_select properly.

 When I created a new resource in rails 3 called Brands, the view
specs for brands had a test which read:

    # Run the generator again with the --webrat flag if you want to
use webrat matchers
    assert_select "form", :action => brands_path, :method => "post" do
      assert_select "input#brand_name", :name => "brand[name]"
      assert_select "input#brand_description", :name =>
"brand[description]"
      assert_select "input#brand_created_by", :name =>
"brand[created_by]"
    end


With my project, I do not want the "created by" attribute
to be set from the new.html.erb entry form.


I read http://content.labnotes.org/assert_select/assert_select.html
and figured I need to use the 'false' equality operator.

It also says the following:


---------- extract starts --------------
assert_select(selector, *values, equality?, message?) { |elems| ... }
assert_select(element, selector, *values, equality?, message?) { |
elems| ... }
---------- extract ends --------------

Alas, my attempts at using it failed.

For  a spec/statement such as 'assert_select
input#brand_created_by", :name => "brand[created_by]',
 I would think that input#brand_created_by would be the 'element' and
the 'selector' combined.

Since I need to use the 'false' equality operator,
1) how do i give null to *values? I have tried the following to no
success and kept getting syntax errors:

a) assert_select "input#brand_created_by", :name =>
"brand[created_by]", '', false   --> spec/views/brands/
new.html.erb_spec.rb:53: syntax error, unexpected ',', expecting
tASSOC (SyntaxError) me => "brand[created_by]", '', false
b)  assert_select "input#brand_created_by", :name =>
"brand[created_by]", nil, false -->
spec/views/brands/new.html.erb_spec.rb:53: syntax error, unexpected
',', expecting tASSOC (SyntaxError)  ...me => "brand[created_by]",
nil, false
c)  assert_select "input#brand_created_by", :name =>
"brand[created_by]", , false --> spec/views/brands/
new.html.erb_spec.rb:53: syntax error, unexpected ',', expecting
keyword_end (SyntaxError) ...:name => "brand[created_by]", , false


 It looks as if any attempts I make to denote that I have no 'values'
to give to it is not working.

Can someone please tell me what the right syntax is for saying, "i
expect not to see the brand[created_by]" input attribute at all in the
rendered form for adding new entries?

Thank you :)
Gordon

On Oct 12, 2011, at 12:58 AM, Gordon wrote:

>      assert_select "input#brand_description", :name =>
> "brand[description]"
>      assert_select "input#brand_created_by", :name =>
> "brand[created_by]"
>    end
>
>
> With my project, I do not want the "created by" attribute to be set from the 
new.html.erb entry form.
>
> I read http://content.labnotes.org/assert_select/assert_select.html and figured 
I need to use the 'false' equality operator.

That's old. Check out 
http://api.rubyonrails.org/classes/ActionDispatch/... 
for the latest.

<snip/>

> Alas, my attempts at using it failed.
>
> For  a spec/statement such as 'assert_select
> input#brand_created_by", :name => "brand[created_by]',
> I would think that input#brand_created_by would be the 'element' and
> the 'selector' combined.

Correct.

> a) assert_select "input#brand_created_by", :name =>
> "brand[created_by]", '', false   --> spec/views/brands/
> new.html.erb_spec.rb:53: syntax error, unexpected ',', expecting
> tASSOC (SyntaxError) me => "brand[created_by]", '', false

This is a problem with Ruby argument ordering working against the 
expressiveness you're looking for. Keyword arguments have to come last. 
So you can say:

  do_something 1, 2, :a, thing, :b => 3

but you can't say

  do_something 1, :a, thing, :b => 3, 2

What _will_ work is this:

  assert_select "input#brand_created_by", false

This leaves out the :name argument, but you don't need it IMO. If you 
really want it, you'd have to do this:


  assert_select "input#brand_created_by", false, :name => 
"brand[created_by]"

But that feels really awkward to me, since the negative assertion is 
expressed in the middle of the argument list

> Can someone please tell me what the right syntax is for saying, "i
> expect not to see the brand[created_by]" input attribute at all in the
> rendered form for adding new entries?

  rendered.should_not have_selector("input#brand_created_by") # ;)

You need Capybara for that, of course, but I think it's easier to grok 
than:

  assert_select "input#brand_created_by", false

HTH,
David

>
> What _will_ work is this:
>
>  assert_select "input#brand_created_by", false
>
>
Hmmm. Sadly it does not work :( See below:

---------------- extract start -------------------------

     Failure/Error: assert_select "input#brand_created_by", false, :name 
=>
"brand[created_by]"
     ArgumentError:
       assertion message must be String or Proc, but Hash was given.
     # (eval):2:in `assert'
     # ./spec/views/brands/new.html.erb_spec.rb:37:in `block (3 levels) 
in
<top (required)>'
     # ./spec/views/brands/new.html.erb_spec.rb:34:in `block (2 levels) 
in
<top (required)

---------------- extract end  -------------------------

On Oct 12, 2011, at 6:53 AM, Gordon Yeong wrote:

> What _will_ work is this:
>
>  assert_select "input#brand_created_by", false

This ^^ does not include :name => "..."

>
>
> Hmmm. Sadly it does not work :( See below:
>
> ---------------- extract start -------------------------
>
>      Failure/Error: assert_select "input#brand_created_by", false, :name => 
"brand[created_by]"

This ^^ does include :name => "....".

What happens when you just run

  assert_select "input#brand_created_by", false

>
>
> This ^^ does include :name => "....".
>
> What happens when you just run
>
>   assert_select "input#brand_created_by", false
>
> this runs successfully but how do I do it with the :name? :( I just want to
be complete and explicit :)

On Oct 13, 2011, at 4:40 AM, Gordon Yeong wrote:

>
> This ^^ does include :name => "....".
>
> What happens when you just run
>
>   assert_select "input#brand_created_by", false
>
> this runs successfully but how do I do it with the :name? :( I just want to be 
complete and explicit :)

I don't know if you can. Maybe somebody on the Rails list knows.

http://groups.google.com/group/rubyonrails-talk

>
> I don't know if you can. Maybe somebody on the Rails list knows.


If it can't, it means that people can't use assert_select to expect
NOT to find a given element with extra attributes (such as :name)
being defined. If that's the case, i think assert_select was either
poorly written OR not completed yet. It's like saying that "if"
conditional works but "if not" only works to a simple extend only :( I
am sure it can be done.
Can someone please show us how?

See this
https://github.com/rails/rails/blob/master/actionp...

seems the syntax is "[name=...]"

On Oct 13, 2011, at 8:56 PM, Gordon wrote:

>> I don't know if you can. Maybe somebody on the Rails list knows.
>
> If it can't, it means that people can't use assert_select to expect
> NOT to find a given element with extra attributes (such as :name)
> being defined. If that's the case, i think assert_select was either
> poorly written OR not completed yet. It's like saying that "if"
> conditional works but "if not" only works to a simple extend only :( I
> am sure it can be done.
> Can someone please show us how?

This is the main benefit of should and should_not vs assertions. 
Virtually every matcher works in with both should and should_not (unless 
it's author explicitly makes it not work that way).

Again, assert_select is part of the Rails library, not RSpec. Please 
post this question to http://groups.google.com/group/rubyonrails-talk 
and I'm sure you'll find someone who uses assert_select and can either 
help you figure out how to do this, or help you work towards making it 
work better.

Cheers,
David