From: Dave Burt <dave@...>
Date: 2006-03-29T14:48:42+09:00
Subject: Re: Can anyone see the obvious msitake I've made?

Kev Jackson wrote:
> Can anyone see the obvious msitake I've made?

It's "msitake" - should be "mistake" ;)

No, really...

> ...
> @@ie.text_field(:id, 
> @test_data['pg_401']['tel_no_2_fld']).value=@test_data['pg_401']['tel_no_2']
> ..
>
> It looks like a perfect place to use a macro to write out the call to 
> ie.text_field at run-time (especially because of the duplicated variables)
>
> I've written a method_missing method in my base class and tried to 
> implement something like
> @@ie.text_field(:id, 
> @test_data['pg_401']['tel_no_1_fld']).value=@test_data['pg_401']['tel_no_1'] 
> => text :id, :pg_401, :tel_no_1
> ...
> Now I've changed @@ie to $ie as it makes more sense (watir and I only want 
> to be driving one ie window at once, so make it a global)

This is the obvious solution to me:

# call: text "pg_401", "tel_no_1"
def text(test_id, field_name)
  $ie.text_field(:id, $test_data[test_id][field_name + '_fld']).value =
    $test_data[test_id][field_name]
end

> in my method_missing definition I have
>
> when /text/=~m.id2name

That will match any method call with "text" in the name. Why do you want 
that? Just define the method you want ("text").

>      #works
>      $ie.text_field(:id, 
> eval("$test_data['#{args[1].to_s}']['#{args[2]}_fld']").to_s).set(eval("$test_data['#{args[1].to_s}']['#{args[2]}']"))

You should not need eval to do this. Not at all. The above line is the same 
as:
     $ie.text_field(:id, ($test_data[args[1].to_s][args[2].to_s + 
'_fld']).to_s).set(
       $test_data[args[1].to_s][args[2].to_s])

Which you can simplify to this if you assume args[1] and args[2] are 
strings:
     $ie.text_field(:id, $test_data[args[1]][args[2] + 
'_fld']).set($test_data[args[1]][args[2]])

Summary: less string interpolation, less to_s, and no eval. Keep it simple, 
just deal with variables. You're just making it needlessly complicated and 
confusing yourself.

>      #doesn't work args[0] = id
>      $ie.text_field("#{args[0].to_sym}", 
> eval("$test_data['#{args[1].to_s}']['#{args[2]}_fld']")).set(eval("$test_data['#{args[1].to_s}']['#{args[2]}']"))

Let's look at this: "#{args[0].to_sym}"

args[0] is being cast to Symbol, then back to String because it's being 
interpolated into one.

Hint: "#{x}" is just a strange way of writing x.to_s. If you expect x to be 
a string, it's the same as just plain old x. "Anything in between quotes" 
will always give you a string.

So, removing the evals and string interpolations, we get:
  $ie.text_field(args[0].to_sym.to_s,  $test_data[args[1].to_s][args[2].to_s 
+ '_fld']).set(
    $test_data[args[1].to_s][args[2].to_s])

And then we can remove all the to_s: the first one is an error (the obvious 
mistake you're trying to locate), and the rest are unnecessary if we assume 
we're being passed a string:
  $ie.text_field(args[0].to_sym,  $test_data[args[1]][args[2] + 
'_fld']).set(
    $test_data[args[1]][args[2]])

A little easier on the eyes?

> What I want to do is to create a call to $ie.text_field with the correct 
> params - as you can see if I specify the symbol :id, it works perfectly 
> (not sure eval is the correct thing to use but it works), however if I try 
> to get the symbol from the args[] and then to_sym before executing, I 
> always get
>
> testScenario(NewApplicationTest):
> Watir::Exception::UnknownObjectException: Unable to locate object, using 
> id and
> form:address1

I would expect Watir to be a little more helpful by either accepting the 
"id" that you're passing, or telling you that it doesn't know how to locate 
objects using a string rather than the symbol it's expecting. I'll ask Bret 
about improving this.

(As I explained earlier in this message, your "to_sym" was interpolated into 
a string, so you were sending a string to text_field.)

> However I've just tried (as I was typing this email)
> $ie.text_field(eval("args[0].to_sym"), 
> eval("$test_data['#{args[1].to_s}']['#{args[2]}_fld']")).set(eval("$test_data['#{args[1].to_s}']['#{args[2]}']"))
>
> And it works! :(
>
> Can anyone explain why #{args[0].to_sym} is not actually evaluating to the 
> :id symbol, but eval(args[0].to_sym) does?  Especially as the error 
> produced from watir is exactly the same as if I'd have typed:

"#{1 + 1}" is the same as (1 + 1).to_s, as I explained earlier.
eval("1 + 1") is the same as (1 + 1).

Cheers,
Dave