Index: includes/form.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/form.inc,v
retrieving revision 1.80
diff -u -r1.80 form.inc
--- includes/form.inc	20 Mar 2006 16:28:10 -0000	1.80
+++ includes/form.inc	24 Mar 2006 17:40:02 -0000
@@ -547,7 +547,7 @@
 function theme_select($element) {
   $select = '';
   $size = $element['#size'] ? ' size="' . $element['#size'] . '"' : '';
-  return theme('form_element', $element['#title'], '<select class="' . _form_get_class('', $element['#required'], form_get_error($element)). '" name="'. $element['#name'] .''. ($element['#multiple'] ? '[]' : '') .'"'. ($element['#multiple'] ? ' multiple="multiple" ' : '') . drupal_attributes($element['#attributes']) .' id="' . $element['#id'] .'" '. $size .'>'. form_select_options($element) .'</select>', $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
+  return theme('form_element', $element['#title'], '<select class="' . _form_get_class($element, ''). '" name="'. $element['#name'] .''. ($element['#multiple'] ? '[]' : '') .'"'. ($element['#multiple'] ? ' multiple="multiple" ' : '') . drupal_attributes($element['#attributes']) .' id="' . $element['#id'] .'" '. $size .'>'. form_select_options($element) .'</select>', $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
 }
 
 function form_select_options($element, $choices = NULL) {
@@ -613,7 +613,7 @@
  */
 function theme_radio($element) {
   $output = '<input type="radio" ';
-  $output .= 'class="'. _form_get_class('form-radio', $element['#required'], form_get_error($element)) .'" ';
+  $output .= 'class="'. _form_get_class($element, 'form-radio') .'" ';
   $output .= 'name="' . $element['#name'] .'" ';
   $output .= 'value="'. $element['#return_value'] .'" ';
   $output .= ($element['#value'] == $element['#return_value']) ? ' checked="checked" ' : ' ';
@@ -809,7 +809,7 @@
 function theme_checkbox($element) {
   $checkbox = '<input ';
   $checkbox .= 'type="checkbox" ';
-  $checkbox .= 'class="'. _form_get_class('form-checkbox', $element['#required'], form_get_error($element)) . '" ';
+  $checkbox .= 'class="'. _form_get_class($element, 'form-checkbox') . '" ';
   $checkbox .= 'name="'. $element['#name'] .'" ';
   $checkbox .= 'id="'. $element['#id'].'" ' ;
   $checkbox .= 'value="'. $element['#return_value'] .'" ';
@@ -904,7 +904,7 @@
     $extra =  '<input class="autocomplete" type="hidden" id="'. $element['#id'] .'-autocomplete" value="'. check_url(url($element['#autocomplete_path'], NULL, NULL, TRUE)) .'" disabled="disabled" />';
   }
 
-  $output = '<input type="text" maxlength="'. $element['#maxlength'] .'" class="'. _form_get_class("form-text$class", $element['#required'], form_get_error($element)) .'" name="'. $element['#name'] .'" id="'. $element['#id'] .'" '. $size .' value="'. check_plain($element['#value']) .'"'. drupal_attributes($element['#attributes']) .' />';
+  $output = '<input type="text" maxlength="'. $element['#maxlength'] .'" class="'. _form_get_class($element, "form-text$class") .'" name="'. $element['#name'] .'" id="'. $element['#id'] .'" '. $size .' value="'. check_plain($element['#value']) .'"'. drupal_attributes($element['#attributes']) .' />';
   return theme('form_element', $element['#title'], $output, $element['#description'], $element['#id'], $element['#required'], form_get_error($element)). $extra;
 }
 
@@ -941,7 +941,7 @@
 
   $cols = $element['#cols'] ? ' cols="'. $element['#cols'] .'"' : '';
 
-  return theme('form_element', $element['#title'], '<textarea'. $cols .' rows="'. $element['#rows'] .'" name="'. $element['#name'] .'" id="' . $element['#id'] .'" class="'. _form_get_class($class, $element['#required'], form_get_error($element)) .'"'. drupal_attributes($element['#attributes']) .'>'. check_plain($element['#value']) .'</textarea>', $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
+  return theme('form_element', $element['#title'], '<textarea'. $cols .' rows="'. $element['#rows'] .'" name="'. $element['#name'] .'" id="' . $element['#id'] .'" class="'. _form_get_class($element, $class) .'"'. drupal_attributes($element['#attributes']) .'>'. check_plain($element['#value']) .'</textarea>', $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
 }
 
 /**
@@ -972,7 +972,7 @@
 function theme_password($element) {
   $size = $element['#size'] ? ' size="'. $element['#size'] .'" ' : '';
 
-  $output = '<input type="password" maxlength="'. $element['#maxlength'] .'" class="'. _form_get_class('form-text', $element['#required'], form_get_error($element)) .'" name="'. $element['#name'] .'" id="'. $element['#id'] .'" '. $size . drupal_attributes($element['#attributes']) .' />';
+  $output = '<input type="password" maxlength="'. $element['#maxlength'] .'" class="'. _form_get_class($element, 'form-text') .'" name="'. $element['#name'] .'" id="'. $element['#id'] .'" '. $size . drupal_attributes($element['#attributes']) .' />';
 
   return theme('form_element', $element['#title'], $output, $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
 }
@@ -1016,11 +1016,42 @@
  * provided by file.inc.
  */
 function theme_file($element) {
-  return theme('form_element', $element['#title'], '<input type="file" class="'. _form_get_class('form-file', $element['#required'], form_get_error($element)) .'" name="'. $element['#name'] .'"'. ($element['#attributes'] ? ' '. drupal_attributes($element['#attributes']) : '') .' id="'. form_clean_id($element['#id']) .'" size="'. $element['#size'] ."\" />\n", $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
+  return theme('form_element', $element['#title'], '<input type="file" class="'. _form_get_class($element, 'form-file') .'" name="'. $element['#name'] .'"'. ($element['#attributes'] ? ' '. drupal_attributes($element['#attributes']) : '') .' id="'. form_clean_id($element['#id']) .'" size="'. $element['#size'] ."\" />\n", $element['#description'], $element['#id'], $element['#required'], form_get_error($element));
 }
 
-function _form_get_class($name, $required, $error) {
-  return $name. ($required ? ' required' : '') . (isset($error) ? ' error' : '');
+/**
+ * Provide class name for form element.
+ *
+ * Adds 'required' and 'error' classes as needed. If a class value has been
+ * set as part of the element's attributes array, this is used and then
+ * unset (to prevent a duplicate class attribute being added).
+ *
+ * Note that this function should be called on a form element before 
+ * attributes are generated with drupal_attributes().
+ *
+ * @param &$element
+ *   The form element
+ * @param $name
+ *   A new class name to be added
+ * @return
+ *   The class name
+ */
+function _form_get_class(&$element, $name) {
+  $class = array();
+  if ($name != '') {
+    $class[] = $name;
+  }
+  if ($element['#required']) {
+    $class[] = 'required';
+  }
+  if (form_get_error($element)){
+    $class[] = 'error';
+  }
+  if (isset($element['#attributes']['class'])) {
+    $class[] = $element['#attributes']['class'];
+    unset($element['#attributes']['class']);
+  }
+  return implode(' ', $class);
 }
 
 /**