Beware of comments in ruby 1.8.7

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I can across a strange bug when upgrading to ruby enterprise 1.8.7 - one of my views displayed incorrectly after the upgrade but it was fine beforehand.

Here's an example of the code I'm referring to:

<table border="1">
<% @services.each do |service| %>
  <% next if service.status_id < 0 # skip inactive services %>
  <tr>
    <td><%= service.name %></td>
    <td><%= service.summary %></td>
  </tr>
<% end %>
</table>

Obviously I'm expecting a table that shows the name and summary of all active services.
i.e. something like this:

That's exactly what I got under ruby 1.8.6, but look at the results when using ruby 1.8.7:

Now why's that happening? The code is pretty basic so surely there's nothing that could go wrong.

Looking into the html source code I discovered that my code was generating this output:

<table border="1">


  Email Notification</td>
    <td>User will receive email notification of events</td>
  </tr>


  Monthly Billing</td>
    <td>User account has been enabled for monthly billing</td>
  </tr>


  Free Reports</td>
    <td>User incurs no charge for viewing reports</td>
  </tr>

</table>

i.e. note the missing <tr><td>

Strange...

Well it turns out that this line was the problem:

  <% next if service.status_id < 0 # skip inactive services %>

It's not the next or the if that causes things to go pear shaped - it's my comment! My comment has the effect of disabling the closing ruby tag so that nothing else is displayed until another closing tag is encountered, i.e. the one after displying the service name: <%= service.name %></td>

Strange that the same code worked fine using ruby 1.8.6, but at least the workaround is easy - just remove comments from the end of code lines, like so:

<table border="1">
<% @services.each do |service| %>
  <% next if service.status_id < 0 %>
  <tr>
    <td><%= service.name %></td>
    <td><%= service.summary %></td>
  </tr>
<% end %>
</table>

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