haml collection and nil --> strftime - ruby

I have a Post object I am rendering in a partial, where one element is
= post.created_at
I want to format the time so I've tried variations of strftime in the partial and as a model hook.
= post.created_at.strftime('etc etc')
&
= post.formatted_time
These work fine when there is something to render, but when there isn't a set of posts, there is an error rendering the page:
undefined method `strftime' for nil:NilClass
only the first works when there are no posts, and creates 1 empty post div on the page.
I need to do something either in the model or template to catch when it is empty and render nothing, which seems basic but I've not yet struck the right search terms to find something I understand to implement.
I'm posting this so someone might help me to think through what I've got so far. Basically I need to format time, which I can do but catch when there is nothing to format.

In Rails you can always use try, which will run the method only if created_at is not nil:
= post.created_at.try(:strftime, 'etc etc')
http://apidock.com/rails/Object/try

Related

how to call clear method on the element object

In my project I have located the text_Field via some other element(via label), something like
element.following_sibling(tag_name: 'input').send_keys 'something'
But now it's typing into the text_field without any problem but I am missing clear method of text_field as it combines both clear and type together. Now I have to call clear method on element.following_sibling(tag_name: 'input') but since it's returning element object, I couldn't do that. Is there any way I can call clear method here? Or can I pass this object by some way to the text_field() method? Any help appreciated.
I know it can be called by converting the watir element into selenium element as given below
element.following_sibling(tag_name: 'input').wd.clear
But here I am missing WATIR waiting time for an element.
This appears to be a limitation in Watir's adjacent methods:
klass = if !plural && opt[:tag_name]
Watir.element_class_for(opt[:tag_name])
elsif !plural
HTMLElement
elsif opt[:tag_name]
Object.const_get("#{Watir.element_class_for(opt[:tag_name])}Collection")
else
HTMLElementCollection
end
Notice that only the :tag_name is used for determining the element's class. For input elements, we need to also consider the type attribute so that we can the right sub-class.
We should fix this in Watir (logged as Issue 878), but in the mean time, you can manually correct the class (ie Watir::TextField) using #to_subtype:
element.following_sibling(tag_name: 'input').to_subtype.clear
I got an answer to my question now.
Here is the answer.
b.text_field(element: element.following_sibling(tag_name: 'input').wd).set 'something'
If anybody has any better idea, please write your answer.Thanks.

Ruby Sinatra Upload Form params Disturbed

Upon submitting a form in Sinatra, I'm coming up with the following error:
App 40327 output: 2018-06-28 02:59:17 - NoMethodError - undefined method `[]' for nil:NilClass:
App 40327 output: /Library/WebServer/Documents/blammo/routes/publish.rb:87:in `block in <class:MyApp>'
The form is a file upload form, and a single text field. Simple. The file goes through, as does the text field. They are both captured just fine.
I submit the params to a method, which is ultimately responsible for generating the error on the following line down the page:
fname = params[:s_single_file_upload][:filename]
The method in question returns fine with a boolean. I've rewritten it a couple of ways and flushed out anything that might trip something I'm
unfamiliar with.
So the params is messed up if this method mentioned above is being called. So fname can't be assigned. I expect the params to be intact
at this point in the code. Is there any destruction if the params are perused before this point? In another language, I've seen params destroyed
in one way or another for some reason, but I'm not sure about Ruby.
I'm not finding any nil:NilClass, but that's exactly what it's reporting. Here's the trigger of this method:
result = Alpha::rf_alpha_sniff(params)
And the module::method:
module Alpha
def self.rf_alpha_sniff(incoming)
qualifiers = %w(alpha bravo charlie delta echo foxtrot)
incoming.delete('captures')
incoming.delete('splat') # take out Mustermann's 'captures' and 'splat'
incoming.delete('s_single_file_upload') # non-perusal 'single_file_upload'
incoming.values.each do |item|
item = item.gsub(" ","_")
Dev::hq_log("item: #{ qualifiers.include?(item.downcase) }")
return true if qualifiers.include?(item.downcase)
end
return false
end
end
So the page progresses fine without this method. When the method is induced any way, the params seem to get screwed up, so the file is pretty much
gone.
How is this method interfering with the params so that it's unavailable later on down the script? I'm expecting it to be fully available everywhere.
Turns out, using incoming.delete was deleting items from the params hash, as it was a reference to the original, instead of using a copy.
So, I have to copy the params by using params.dup (duplicate) so they are not the same object.
Having a view of the params hash post-testing-method, showed me that objects were indeed deleted. Another one solved.

Finding only the new rows added to a table

I have the following code which is supposed to get me only the new events added to the table from the last time i checked the table.
events=#browser.table( :id =>'table_events').tbody.rows
....
some code
....
events_new=#browser.table( :id =>'table_events').tbody.rows
events=events_new - events # not working !!
Im getting the fallowing error :
undefined method `-' for #<Watir::TableRowCollection:0x007fccb9ba2358> (NoMethodError)
I understand that the "-" predicate is wrong of course, but is there a method that does what i need or do i need to go over all the TableRowCollection and find the new rows manually?
You could try converting the TableRowCollection to an array, which does support subtraction:
events = events_new.to_a - events.to_a
That will work provided the elements have a useful == method defined - and it looks like they do.
Correction: actually, because array subtraction is implemented using a hash table for efficiency (view source here if you're curious), it is not the TableRow#== method that is important but the TableRow#hash method. Fortunately, it looks like Watir implements that as well.

PageObject with Ruby - set text in a text field only works in the main file

I'm automating a site that has a page with a list of options selected by a radio button. When selecting one of the radios, a text field and a select list are presented.
I created a file (test_contracting.rb) that is the one through which I execute the test (ruby test_contracting.rb) and some other classes to represent my page.
On my class ContractPage, I have the following element declaration:
checkbox(:option_sub_domain, :id => "option_sub_domain")
text_field(:domain, :id => "domain_text")
select_list(:tld, :id => "domain_tld")
I've created in the ContractPage a method that sets the configuration of the domain like this:
def configure_domain(config={})
check_option_sub_domain
domain = config[:domain]
tld = config[:tld]
end
When I call the method configure_domain from the test_contracting.rb, it selects the radio button, but it doesn't fill the field with the values. The params are getting into the method correctly. I've checked it using "puts". Even if I change the params to a general string like "bla" it doesnt work. The annoying point is that if on test_contracting.rb I call the exact same components, it works.
my_page_instance = ContractPage.new(browser)
my_page_instance.domain = "bla"
my_page_instance.tld = ".com"
What I found to work was to in the configure_domain method, implement the following:
domain_element.value = config[:domain]
tld_element.send_keys config[:locaweb_domain]
Then it worked.
The documentation for the PageObjects module that I'm using as reference can be found here: http://rubydoc.info/github/cheezy/page-object/master/PageObject/Accessors#select_list-instance_method
Do you guys have any explation on why the method auto generated by the pageobject to set the value of the object didnt work in this scope/context ?
By the way, a friend tried the same thing with Java and it failed as well.
In ruby all equals methods (methods that end with the = sign) need to have a receiver. Let me show you some code that will demonstrate why. Here is the code that sets a local variable to a value:
domain = "blah"
and here is the code that calls the domain= method:
domain = "blah"
In order for ruby to know that you are calling a method instead of setting a local variable you need to add a receiver. Simply change your method above to this and it will work:
def configure_domain(config={})
check_option_sub_domain
self.domain = config[:domain]
self.tld = config[:tld]
end
I'm pretty new to this world of Selenium and page objects but maybe one of my very recent discoveries might help you.
I found that that assignment methods for the select_list fields only worked for me once I started using "self" in front. This is what I have used to access it within my page object code. e.g., self.my_select_list="my select list value"
Another note - The send_keys workaround you mention is clever and might do the trick for a number of uses, but in my case the select list values are variable and may have several options starting with the same letter.
I hope something in here is useful to you.
UPDATE (Jan 3/12)
On diving further into the actual Ruby code for the page object I discovered that the select_list set is also using send_keys, so in actuality I still have the same limitation here as the one I noted using the send_keys workaround directly. sigh So much to learn, so little time!

Rails 3 - "to_f" fixes the issue, but I'm not sure why

In my model Reports I have an attribute called :total. In Reports view I show the last 4 entries of this :total attribute (from previous Reports) on a chart. I found that when there wasn't a previous entry, the chart wouldn't render. When I went back and added "to_f" to the calculation, the chart would render and just show "0" where there was no entry. I'm glad it worked, but it was just a wild guess. Why did this work?
Your values were probably nil. I'm guessing your formatter wasn't keen on working with nils. However, nil implements a .to_f which returns 0.0, which your formatter could handle without crashing.
i.e.
nil.to_f # => 0.0
Without seeing your code all I can do is guess.
I'm guessing that report.total was nil for some of the reports in your database and whatever code you are using to make charts can not handle nil values.
For example, nil/2 will throw an exception but nil.to_f/2 will not.

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