MDL-32220 question import: files sometimes stored in the wrong context.

Sadly, this involves a small API change, but I don't believe anyone was
using the argument I had to remove (because we were sometimes passing a
wrong value, and there is not way to compute the right value at that
point in the code.)

Also sadly, the code to compute the context we are importing into is now
rather spaghetti-like, but it works.

Conflicts:

	question/format/examview/format.php
	question/format/learnwise/format.php
	question/format/webct/format.php

Conflicts:

	question/format/upgrade.txt

question/format.php

@@ -128,6 +128,7 @@ public function setCategory($category) {
             debugging('You shouldn\'t call setCategory after setQuestions');
         }
         $this->category = $category;
+        $this->importcontext = get_context_instance_by_id($this->category->contextid);
     }
 
     /**
@@ -311,9 +312,6 @@ public function importpreprocess() {
     public function importprocess($category) {
         global $USER, $CFG, $DB, $OUTPUT;
 
-        $context = $category->context;
-        $this->importcontext = $context;
-
         // reset the timer in case file upload was slow
         set_time_limit(0);
 
@@ -325,7 +323,7 @@ public function importprocess($category) {
             return false;
         }
 
-        if (!$questions = $this->readquestions($lines, $context)) {   // Extract all the questions
+        if (!$questions = $this->readquestions($lines)) {   // Extract all the questions
             echo $OUTPUT->notification(get_string('noquestionsinfile', 'question'));
             return false;
         }
@@ -397,7 +395,7 @@ public function importprocess($category) {
                 }
                 continue;
             }
-            $question->context = $context;
+            $question->context = $this->importcontext;
 
             $count++;
 
@@ -415,13 +413,13 @@ public function importprocess($category) {
             if (isset($question->questiontextfiles)) {
                 foreach ($question->questiontextfiles as $file) {
                     question_bank::get_qtype($question->qtype)->import_file(
-                            $context, 'question', 'questiontext', $question->id, $file);
+                            $this->importcontext, 'question', 'questiontext', $question->id, $file);
                 }
             }
             if (isset($question->generalfeedbackfiles)) {
                 foreach ($question->generalfeedbackfiles as $file) {
                     question_bank::get_qtype($question->qtype)->import_file(
-                            $context, 'question', 'generalfeedback', $question->id, $file);
+                            $this->importcontext, 'question', 'generalfeedback', $question->id, $file);
                 }
             }
 
@@ -507,6 +505,7 @@ protected function create_category_path($catpath) {
         } else {
             $context = get_context_instance_by_id($this->category->contextid);
         }
+        $this->importcontext = $context;
 
         // Now create any categories that need to be created.
         foreach ($catnames as $catname) {
@@ -556,14 +555,19 @@ protected function readdata($filename) {
      * readquestion().   Questions are defined as anything
      * between blank lines.
      *
+     * NOTE this method used to take $context as a second argument. However, at
+     * the point where this method was called, it was impossible to know what
+     * context the quetsions were going to be saved into, so the value could be
+     * wrong. Also, none of the standard question formats were using this argument,
+     * so it was removed. See MDL-32220.
+     *
      * If your format does not use blank lines as a delimiter
      * then you will need to override this method. Even then
      * try to use readquestion for each question
      * @param array lines array of lines from readdata
-     * @param object $context
      * @return array array of question objects
      */
-    protected function readquestions($lines, $context) {
+    protected function readquestions($lines) {
 
         $questions = array();
         $currentquestion = array();
@@ -583,7 +587,7 @@ protected function readquestions($lines, $context) {
         }
 
         if (!empty($currentquestion)) {  // There may be a final question
-            if ($question = $this->readquestion($currentquestion, $context)) {
+            if ($question = $this->readquestion($currentquestion)) {
                 $questions[] = $question;
             }
         }

question/format/examview/format.php

@@ -149,7 +149,7 @@ function cleanUnicode($text) {
         return str_replace('’', "'", $text);
     }
 
-    function readquestions($lines) {
+    protected function readquestions($lines) {
         /// Parses an array of lines into an array of questions,
         /// where each item is a question object as defined by
         /// readquestion().

question/format/learnwise/format.php

@@ -46,7 +46,7 @@ function provide_import() {
         return true;
     }
 
-    function readquestions($lines) {
+    protected function readquestions($lines) {
         $questions = array();
         $currentquestion = array();
 

question/format/upgrade.txt

@@ -0,0 +1,9 @@
+This files describes API changes for question import/export format plugins.
+
+=== 2.1.5 / 2.2.3 / 2.3 ===
+
+* The readquestions method used to take a second argument $context. However, at
+  the point where this method was called, it was impossible to know what
+  context the quetsions were going to be saved into, so the value could be
+  wrong. Also, none of the standard question formats were using this argument,
+  so it was removed. See MDL-32220.

question/format/webct/format.php

@@ -172,7 +172,7 @@ function provide_import() {
       return true;
     }
 
-    function readquestions ($lines) {
+    protected function readquestions($lines) {
         $webctnumberregex =
                 '[+-]?([0-9]+(\\.[0-9]*)?|\\.[0-9]+)((e|E|\\*10\\*\\*)([+-]?[0-9]+|\\([+-]?[0-9]+\\)))?';