title: Rails / Formtastic - Validation isn't occuring
body: <p>I'm using formtastic to validate forms:</p>
  
  <pre><code>&lt;%= semantic_form_for @user do |f| %&gt;
    &lt;ul class="formItem"&gt;         
      &lt;%= f.input :username, :required =&gt; true, :label =&gt; "Your Username", :input_html =&gt; { :class =&gt; 'double' } %&gt;&lt;br clear="all" /&gt;
      &lt;p class="fieldExplanation"&gt;Your username is made public to other people on the site.&lt;/p&gt;                       
    &lt;/ul&gt; 
    &lt;ul class="actions"&gt;      
      &lt;%= f.commit_button("Save my profile and make a match &gt;", :class =&gt; "submitForm") %&gt;    
    &lt;/ul&gt;
  &lt;% end %&gt;
  </code></pre>
  
  <p>It's visually working - the form renders with a little asterisk to indicate that it understood :required => true - but when the page posts, it doesn't trigger validation with an error; instead, it simply moves on to the next page, as if it was successful. </p>
  
  <p>I feel like I'm missing a simple setting somewhere to turn validation on, or perhaps I'm doing something wrong in my controller?</p>
  
  <pre><code>def update
   @user = User.find(params[:id])     
   respond_to do |format|
     if @user.update_attributes(params[:user])        
        format.html { redirect_to(match_user_path(@user), :notice =&gt; 'User was successfully updated.') }              
     else
       format.html { render :action =&gt; "edit" }        
     end
   end
  end
  </code></pre>
  
  <p>Thanks in advance. </p>