From 8034ad8be2613004d758e91016d9f1b173796095 Mon Sep 17 00:00:00 2001
From: Paul Holden <paulh@moodle.com>
Date: Thu, 6 Jul 2023 21:10:11 +0100
Subject: [PATCH 1/2] MDL-69187 files: normalize retrieval of mimetypes from
 groups array.

Ensure that the following both return consistently, so that filepicker
form elements behave the same for each when defining "accepted_types":

    '.html, .txt'
    ['.html', '.txt']
---
 lib/filelib.php | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/filelib.php b/lib/filelib.php
index 93edcb21a72..73f4f3b7feb 100644
--- a/lib/filelib.php
+++ b/lib/filelib.php
@@ -2068,9 +2068,12 @@ function get_mimetype_description($obj, $capitalise=false) {
  */
 function file_get_typegroup($element, $groups) {
     static $cached = array();
+
+    // Turn groups into a list.
     if (!is_array($groups)) {
-        $groups = array($groups);
+        $groups = preg_split('/[\s,;:"\']+/', $groups, -1, PREG_SPLIT_NO_EMPTY);
     }
+
     if (!array_key_exists($element, $cached)) {
         $cached[$element] = array();
     }

From 6dcb45597350c8b5db3a28a75a9d7a15b1879ccd Mon Sep 17 00:00:00 2001
From: Andrew Nicols <andrew@nicols.co.uk>
Date: Tue, 22 Aug 2023 22:47:32 +0800
Subject: [PATCH 2/2] MDL-69187 core_file: Unit test for file_get_typegroup
 string types

---
 lib/tests/filelib_test.php | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/lib/tests/filelib_test.php b/lib/tests/filelib_test.php
index d5c7a43467b..9685e9a3db3 100644
--- a/lib/tests/filelib_test.php
+++ b/lib/tests/filelib_test.php
@@ -1985,6 +1985,42 @@ EOF;
             ['noclean' => true, 'context' => $syscontext], $syscontext, 'core', 'some', 1);
         $this->assertSame($text, $result->some);
     }
+
+    /**
+     * Tests for file_get_typegroup to check that both arrays, and string values are accepted.
+     *
+     * @dataProvider file_get_typegroup_provider
+     * @param string|array $group
+     * @param string $expected
+     */
+    public function test_file_get_typegroup(
+        $group,
+        string $expected
+    ): void {
+        $result = file_get_typegroup('type', $group);
+        $this->assertContains($expected, $result);
+    }
+
+    public static function file_get_typegroup_provider(): array {
+        return [
+            'Array of values' => [
+                ['.html', '.htm'],
+                'text/html',
+            ],
+            'String of comma-separated values' => [
+                '.html, .htm',
+                'text/html',
+            ],
+            'String of colon-separated values' => [
+                '.html : .htm',
+                'text/html',
+            ],
+            'String of semi-colon-separated values' => [
+                '.html ; .htm',
+                'text/html',
+            ],
+        ];
+    }
 }
 
 /**