From 4d3d5b3687378e600aba91005052b5efd843d4fb Mon Sep 17 00:00:00 2001
From: ferranrecio <ferran@moodle.com>
Date: Tue, 17 Sep 2024 09:37:35 +0200
Subject: [PATCH] MDL-82845 core_course: method to get all cm_info from a
 section_info

---
 .upgradenotes/MDL-82845-2024091708245574.yml |  8 +++++
 lib/modinfolib.php                           | 24 ++++++++++++++
 lib/tests/modinfolib_test.php                | 34 ++++++++++++++++++++
 3 files changed, 66 insertions(+)
 create mode 100644 .upgradenotes/MDL-82845-2024091708245574.yml

diff --git a/.upgradenotes/MDL-82845-2024091708245574.yml b/.upgradenotes/MDL-82845-2024091708245574.yml
new file mode 100644
index 00000000000..f7e0c5ebbe2
--- /dev/null
+++ b/.upgradenotes/MDL-82845-2024091708245574.yml
@@ -0,0 +1,8 @@
+issueNumber: MDL-82845
+notes:
+  core:
+    - message: >-
+        The section_info class now includes a new method called
+        get_sequence_cm_infos that retrieves all cm_info instances associated
+        with the course section.
+      type: improved
diff --git a/lib/modinfolib.php b/lib/modinfolib.php
index 252d64ea649..a986c56dbb5 100644
--- a/lib/modinfolib.php
+++ b/lib/modinfolib.php
@@ -3226,6 +3226,9 @@ class section_info implements IteratorAggregate {
      */
     private ?sectiondelegate $_delegateinstance = null;
 
+    /** @var cm_info[]|null Section cm_info activities, null when it is not loaded yet. */
+    private array|null $_sequencecminfos = null;
+
     /**
      * @var bool|null $_isorphan True if the section is orphan for some reason.
      */
@@ -3625,6 +3628,27 @@ class section_info implements IteratorAggregate {
         }
     }
 
+    /**
+     * Returns the course modules in this section.
+     *
+     * @return cm_info[]
+     */
+    public function get_sequence_cm_infos(): array {
+        if ($this->_sequencecminfos !== null) {
+            return $this->_sequencecminfos;
+        }
+        $sequence = $this->modinfo->sections[$this->_sectionnum] ?? [];
+        $cms = $this->modinfo->get_cms();
+        $result = [];
+        foreach ($sequence as $cmid) {
+            if (isset($cms[$cmid])) {
+                $result[] = $cms[$cmid];
+            }
+        }
+        $this->_sequencecminfos = $result;
+        return $result;
+    }
+
     /**
      * Returns course ID - from course_sections table
      *
diff --git a/lib/tests/modinfolib_test.php b/lib/tests/modinfolib_test.php
index a53a9dba31c..d2ecf1b6d12 100644
--- a/lib/tests/modinfolib_test.php
+++ b/lib/tests/modinfolib_test.php
@@ -2223,4 +2223,38 @@ class modinfolib_test extends advanced_testcase {
         $delegatedsection = $modinfo->get_section_info($delegatedsection->section);
         $this->assertTrue($delegatedsection->is_orphan());
     }
+
+    /**
+     * Test for section_info::get_sequence_cm_infos
+     *
+     * @covers \section_info::get_sequence_cm_infos
+     * @return void
+     */
+    public function test_section_get_sequence_cm_infos(): void {
+        $this->resetAfterTest();
+
+        $course = $this->getDataGenerator()->create_course(['numsections' => 2]);
+        $cm1 = $this->getDataGenerator()->create_module('page', ['course' => $course], ['section' => 0]);
+        $cm2 = $this->getDataGenerator()->create_module('page', ['course' => $course], ['section' => 1]);
+        $cm3 = $this->getDataGenerator()->create_module('page', ['course' => $course], ['section' => 1]);
+        $cm4 = $this->getDataGenerator()->create_module('page', ['course' => $course], ['section' => 1]);
+
+        $modinfo = get_fast_modinfo($course->id);
+
+        $sectioninfo = $modinfo->get_section_info(0);
+        $cms = $sectioninfo->get_sequence_cm_infos();
+        $this->assertCount(1, $cms);
+        $this->assertEquals($cm1->cmid, $cms[0]->id);
+
+        $sectioninfo = $modinfo->get_section_info(1);
+        $cms = $sectioninfo->get_sequence_cm_infos();
+        $this->assertCount(3, $cms);
+        $this->assertEquals($cm2->cmid, $cms[0]->id);
+        $this->assertEquals($cm3->cmid, $cms[1]->id);
+        $this->assertEquals($cm4->cmid, $cms[2]->id);
+
+        $sectioninfo = $modinfo->get_section_info(2);
+        $cms = $sectioninfo->get_sequence_cm_infos();
+        $this->assertCount(0, $cms);
+    }
 }