Rails - Jun 2009 - Need help with assert_select semantics

I have this type of table row generated in a view:

...
      <tr class="forex_rate_line"
id="row_1_currency_exchange_rate_729">
        <!-- #  id:integer:not null:primary key -->
        <td class="base_currency">CAD </td>
        <td class="quote_currency">USD </td>
        <td class="effective_date">2009-04-05 </td>
        <td class="forex_type">TEST </td>
        <td class="base_rate_is_0.8444">
          1.184273
        </td>
        <td>features test </td>
      </tr>
...

There are many instances of dorex_rate_line and I wish to select only
those that also contain a class "base_rate_is_0.8444" and I wish to
valiously test that there are: at least, exactly, or at most, N
occurrences.

For the exact match I have tried this:

  count = 1
  assert_select(  ''.base_rate_is_0.8444'', { :count =>
count.to_i } )

But that gives this error:

  Expected at least 1 element matching "base_rate_is_0.8444", found 0.
      <false> is not true. (Test::Unit::AssertionFailedError)

On the other hand, using exactly the same data I do this and it works as
I anticipate:

    count = 1
    code = ''USD''
    assert_select(  ''.quote_currency'',
                { :maximum => count.to_i,
                  :text => code })

So, what is it that I am misapprehending with assert_select?
-- 
Posted via http://www.ruby-forum.com/.

James Byrne wrote:
> 
> So, what is it that I am misapprehending with assert_select?
That one may not have a ''.'' form part of a class value.

  ''.base_rate_is_0.8444'' s/b
  ''.base_rate_is_0_8444''
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