MDL-62534 course formats: do not purge empty sections on upgrade

course/format/topics/db/upgradelib.php

@@ -26,9 +26,13 @@
 
 /**
  * This method finds all courses in 'topics' format that have actual number of sections
- * bigger than their 'numsections' course format option.
- * For each such course we call {@link format_topics_upgrade_hide_extra_sections()} and
- * either delete or hide "orphaned" sections.
+ * different than their 'numsections' course format option.
+ *
+ * For courses where there are more sections than numsections, we call
+ * {@link format_topics_upgrade_hide_extra_sections()} and
+ * either delete or hide "orphaned" sections. For courses where there are fewer sections
+ * than numsections, we call {@link format_topics_upgrade_add_empty_sections()} to add
+ * these sections.
  */
 function format_topics_upgrade_remove_numsections() {
     global $DB;
@@ -49,6 +53,7 @@ function format_topics_upgrade_remove_numsections() {
     $actual = $DB->get_records_sql_menu($sql1, $params);
     $numsections = $DB->get_records_sql_menu($sql2, $params);
     $needfixing = [];
+    $needsections = [];
 
     $defaultnumsections = get_config('moodlecourse', 'numsections');
 
@@ -60,6 +65,8 @@ function format_topics_upgrade_remove_numsections() {
         }
         if ($sectionsactual > $n) {
             $needfixing[$courseid] = $n;
+        } else if ($sectionsactual < $n) {
+            $needsections[$courseid] = $n;
         }
     }
     unset($actual);
@@ -69,6 +76,10 @@ function format_topics_upgrade_remove_numsections() {
         format_topics_upgrade_hide_extra_sections($courseid, $numsections);
     }
 
+    foreach ($needsections as $courseid => $numsections) {
+        format_topics_upgrade_add_empty_sections($courseid, $numsections);
+    }
+
     $DB->delete_records('course_format_options', ['format' => 'topics', 'sectionid' => 0, 'name' => 'numsections']);
 }
 
@@ -115,3 +126,19 @@ function format_topics_upgrade_hide_extra_sections($courseid, $numsections) {
         $DB->execute("UPDATE {course_sections} SET visible = 0 WHERE id " . $sql, $params);
     }
 }
+
+/**
+ * This method adds empty sections to courses which have fewer sections than their
+ * 'numsections' course format option and adds these empty sections.
+ *
+ * @param int $courseid
+ * @param int $numsections
+ */
+function format_topics_upgrade_add_empty_sections($courseid, $numsections) {
+    global $DB;
+    $existingsections = $DB->get_fieldset_sql('SELECT section from {course_sections} WHERE course = ?', [$courseid]);
+    $newsections = array_diff(range(0, $numsections), $existingsections);
+    foreach ($newsections as $sectionnum) {
+        course_create_section($courseid, $sectionnum, true);
+    }
+}

course/format/topics/tests/format_topics_upgrade_test.php

@@ -125,4 +125,29 @@ public function test_numsections_hide_non_empty() {
         // The module is still visible.
         $this->assertEquals(1, $DB->get_field('course_modules', 'visible', ['id' => $cm->cmid]));
     }
+
+    /**
+     * Test upgrade step to add empty sections.
+     */
+    public function test_numsections_add_empty_sections() {
+        global $DB;
+
+        $this->resetAfterTest(true);
+
+        $params = array('format' => 'topics', 'numsections' => 16, 'startdate' => 1445644800);
+        $course = $this->getDataGenerator()->create_course($params);
+
+        // This test is executed after 'numsections' option was already removed.
+        // Set the 'numsections' course format value to 18, simulating the scenario in which there are fewer real sections.
+        $DB->insert_record('course_format_options', ['courseid' => $course->id, 'format' => 'topics',
+            'sectionid' => 0, 'name' => 'numsections', 'value' => '18']);
+
+        // There are 16 sections.
+        $this->assertEquals(17, $DB->count_records('course_sections', ['course' => $course->id]));
+
+        format_topics_upgrade_remove_numsections();
+
+        // Confirm that the upgrade method added the missing empty sections.
+        $this->assertEquals(19, $DB->count_records('course_sections', ['course' => $course->id]));
+    }
 }

course/format/weeks/db/upgradelib.php

@@ -25,10 +25,14 @@
 defined('MOODLE_INTERNAL') || die();
 
 /**
- * This method finds all courses in 'weeks' format that have actual number of sections
- * bigger than their 'numsections' course format option.
- * For each such course we call {@link format_weeks_upgrade_hide_extra_sections()} and
- * either delete or hide "orphaned" sections.
+ * This method finds all courses in 'topics' format that have actual number of sections
+ * different than their 'numsections' course format option.
+ *
+ * For courses where there are more sections than numsections, we call
+ * {@link format_weeks_upgrade_hide_extra_sections()} and
+ * either delete or hide "orphaned" sections. For courses where there are fewer sections
+ * than numsections, we call {@link format_weeks_upgrade_add_empty_sections()} to add
+ * these sections.
  */
 function format_weeks_upgrade_remove_numsections() {
     global $DB;
@@ -49,6 +53,7 @@ function format_weeks_upgrade_remove_numsections() {
     $actual = $DB->get_records_sql_menu($sql1, $params);
     $numsections = $DB->get_records_sql_menu($sql2, $params);
     $needfixing = [];
+    $needsections = [];
 
     $defaultnumsections = get_config('moodlecourse', 'numsections');
 
@@ -60,6 +65,8 @@ function format_weeks_upgrade_remove_numsections() {
         }
         if ($sectionsactual > $n) {
             $needfixing[$courseid] = $n;
+        } else if ($sectionsactual < $n) {
+            $needsections[$courseid] = $n;
         }
     }
     unset($actual);
@@ -69,6 +76,10 @@ function format_weeks_upgrade_remove_numsections() {
         format_weeks_upgrade_hide_extra_sections($courseid, $numsections);
     }
 
+    foreach ($needsections as $courseid => $numsections) {
+        format_weeks_upgrade_add_empty_sections($courseid, $numsections);
+    }
+
     $DB->delete_records('course_format_options', ['format' => 'weeks', 'sectionid' => 0, 'name' => 'numsections']);
 }
 
@@ -115,3 +126,19 @@ function format_weeks_upgrade_hide_extra_sections($courseid, $numsections) {
         $DB->execute("UPDATE {course_sections} SET visible = 0 WHERE id " . $sql, $params);
     }
 }
+
+/**
+ * This method adds empty sections to courses which have fewer sections than their
+ * 'numsections' course format option and adds these empty sections.
+ *
+ * @param int $courseid
+ * @param int $numsections
+ */
+function format_weeks_upgrade_add_empty_sections($courseid, $numsections) {
+    global $DB;
+    $existingsections = $DB->get_fieldset_sql('SELECT section from {course_sections} WHERE course = ?', [$courseid]);
+    $newsections = array_diff(range(0, $numsections), $existingsections);
+    foreach ($newsections as $sectionnum) {
+        course_create_section($courseid, $sectionnum, true);
+    }
+}

course/format/weeks/tests/format_weeks_upgrade_test.php

@@ -125,4 +125,29 @@ public function test_numsections_hide_non_empty() {
         // The module is still visible.
         $this->assertEquals(1, $DB->get_field('course_modules', 'visible', ['id' => $cm->cmid]));
     }
+
+    /**
+     * Test upgrade step to add empty sections.
+     */
+    public function test_numsections_add_empty_sections() {
+        global $DB;
+
+        $this->resetAfterTest(true);
+
+        $params = array('format' => 'weeks', 'numsections' => 16, 'startdate' => 1445644800);
+        $course = $this->getDataGenerator()->create_course($params);
+
+        // This test is executed after 'numsections' option was already removed.
+        // Set the 'numsections' course format value to 18, simulating the scenario in which there are fewer real sections.
+        $DB->insert_record('course_format_options', ['courseid' => $course->id, 'format' => 'weeks',
+            'sectionid' => 0, 'name' => 'numsections', 'value' => '18']);
+
+        // There are 16 sections.
+        $this->assertEquals(17, $DB->count_records('course_sections', ['course' => $course->id]));
+
+        format_weeks_upgrade_remove_numsections();
+
+        // Confirm that the upgrade method added the missing empty sections.
+        $this->assertEquals(19, $DB->count_records('course_sections', ['course' => $course->id]));
+    }
 }