Remove excess white spaces in Fill Blanks questions - refs BT#12630

main/exercise/exercise.class.php

@@ -3676,19 +3676,14 @@ class Exercise
                         if (!$switchableAnswerSet) {
                             // not switchable answer, must be in the same place than teacher order
                             for ($i = 0; $i < count($listCorrectAnswers['tabwords']); $i++) {
-                                $studentAnswer = isset($choice[$i]) ? trim($choice[$i]) : '';
+                                $studentAnswer = isset($choice[$i]) ? $choice[$i] : '';
                                 $correctAnswer = $listCorrectAnswers['tabwords'][$i];
 
                                 // This value is the user input, not escaped while correct answer is escaped by fckeditor
                                 // Works with cyrillic alphabet and when using ">" chars see #7718 #7610 #7618
                                 // ENT_QUOTES is used in order to transform ' to &#039;
                                 if (!$from_database) {
-                                    $studentAnswer = htmlentities(
-                                        api_utf8_encode($studentAnswer),
-                                        ENT_QUOTES
-                                    );
-                                    // fix apostrophe
-                                    $studentAnswer = str_replace('&#039;', '&#39;', $studentAnswer);
+                                    $studentAnswer = FillBlanks::clearStudentAnswer($studentAnswer);
                                 }
 
                                 $isAnswerCorrect = 0;

main/exercise/fill_blanks.class.php

@@ -1322,4 +1322,18 @@ class FillBlanks extends Question
 
         return $isCorrect;
     }
+
+    /**
+     * Clear the answer entered by student
+     * @param string $answer
+     * @return string
+     */
+    public static function clearStudentAnswer($answer)
+    {
+        $answer = htmlentities(api_utf8_encode($answer), ENT_QUOTES);
+        $answer = str_replace(''', ''', $answer); // fix apostrophe
+        $answer = api_preg_replace('/\s\s+/', ' ', $answer); // replace excess white spaces
+
+        return trim($answer);
+    }
 }