[BUGFIX] Render prepended option tag always in first place

Currently the prepend option is rendered together with the options
argument from select viewhelper. Using the option "optionsAfterContent"
renders also the prepend option after the children. The preprend
option is now rendered always in the first place.

Resolves: #79584
Releases: master, 8.7
Change-Id: Ia58c3b7d9b26d00cbda4d7ebce2a881a7129b331
Reviewed-on: https://review.typo3.org/51501


Reviewed-by: Jan Helke <typo3@helke.de>
Tested-by: Jan Helke <typo3@helke.de>
Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>

typo3/sysext/fluid/Classes/ViewHelpers/Form/SelectViewHelper.php

@@ -149,6 +149,7 @@ class SelectViewHelper extends \TYPO3\CMS\Fluid\ViewHelpers\Form\AbstractFormFie
         }
 
         $this->viewHelperVariableContainer->addOrUpdate(static::class, 'selectedValue', $this->getSelectedValue());
+        $prependContent = $this->renderPrependOptionTag();
         $tagContent = $this->renderOptionTags($options);
         $childContent = $this->renderChildren();
         $this->viewHelperVariableContainer->remove(static::class, 'selectedValue');
@@ -158,6 +159,7 @@ class SelectViewHelper extends \TYPO3\CMS\Fluid\ViewHelpers\Form\AbstractFormFie
         } else {
             $tagContent .= $childContent;
         }
+        $tagContent = $prependContent . $tagContent;
 
         $this->tag->forceClosingTag(true);
         $this->tag->setContent($tagContent);
@@ -165,13 +167,12 @@ class SelectViewHelper extends \TYPO3\CMS\Fluid\ViewHelpers\Form\AbstractFormFie
         return $content;
     }
 
-    /**
-     * Render the option tags.
+   /*
+     * Render prepended option tag
      *
-     * @param array $options the options for the form.
-     * @return string rendered tags.
+     * @return string rendered prepended empty option
      */
-    protected function renderOptionTags($options)
+    protected function renderPrependOptionTag()
     {
         $output = '';
         if ($this->hasArgument('prependOptionLabel')) {
@@ -179,6 +180,18 @@ class SelectViewHelper extends \TYPO3\CMS\Fluid\ViewHelpers\Form\AbstractFormFie
             $label = $this->arguments['prependOptionLabel'];
             $output .= $this->renderOptionTag($value, $label, false) . LF;
         }
+        return $output;
+    }
+
+    /**
+     * Render the option tags.
+     *
+     * @param array $options the options for the form.
+     * @return string rendered tags.
+     */
+    protected function renderOptionTags($options)
+    {
+        $output = '';
         foreach ($options as $value => $label) {
             $isSelected = $this->isSelected($value);
             $output .= $this->renderOptionTag($value, $label, $isSelected) . LF;