From 0ef74b27bef176a29f6814ba9a21fd2ba46e8c49 Mon Sep 17 00:00:00 2001
From: Davo Smith <davo.smith@synergy-learning.com>
Date: Wed, 19 Jul 2017 16:31:52 +0100
Subject: [PATCH 1/2] MDL-59195 assignsubmission_comments: fix permission
 checks

---
 mod/assign/submission/comments/lib.php      | 9 ---------
 mod/assign/submission/comments/locallib.php | 1 -
 2 files changed, 10 deletions(-)

diff --git a/mod/assign/submission/comments/lib.php b/mod/assign/submission/comments/lib.php
index 09666b0ca16..71caab65319 100644
--- a/mod/assign/submission/comments/lib.php
+++ b/mod/assign/submission/comments/lib.php
@@ -48,15 +48,6 @@ function assignsubmission_comments_comment_validate(stdClass $options) {
     if ($assignment->get_instance()->id != $submission->assignment) {
         throw new comment_exception('invalidcontext');
     }
-    $canview = false;
-    if ($submission->userid) {
-        $canview = $assignment->can_view_submission($submission->userid);
-    } else {
-        $canview = $assignment->can_view_group_submission($submission->groupid);
-    }
-    if (!$canview) {
-        throw new comment_exception('nopermissiontocomment');
-    }
 
     return true;
 }
diff --git a/mod/assign/submission/comments/locallib.php b/mod/assign/submission/comments/locallib.php
index 16ac94d7c81..d3b4a3b9849 100644
--- a/mod/assign/submission/comments/locallib.php
+++ b/mod/assign/submission/comments/locallib.php
@@ -69,7 +69,6 @@ class assign_submission_comments extends assign_submission_plugin {
         $options->displaycancel = true;
 
         $comment = new comment($options);
-        $comment->set_view_permission(true);
 
         $o = $this->assignment->get_renderer()->container($comment->output(true), 'commentscontainer');
         return $o;

From 0d5f10d1ff364555286eda63fe008e69d10e34b9 Mon Sep 17 00:00:00 2001
From: Davo Smith <davo.smith@synergy-learning.com>
Date: Mon, 21 Aug 2017 10:20:06 +0100
Subject: [PATCH 2/2] MDL-59195 mod_assign: add behat tests for comments error

---
 .../behat/assign_comments_no_error.feature    | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)
 create mode 100644 mod/assign/tests/behat/assign_comments_no_error.feature

diff --git a/mod/assign/tests/behat/assign_comments_no_error.feature b/mod/assign/tests/behat/assign_comments_no_error.feature
new file mode 100644
index 00000000000..96e6fb3ceb6
--- /dev/null
+++ b/mod/assign/tests/behat/assign_comments_no_error.feature
@@ -0,0 +1,26 @@
+@mod @mod_assign
+Feature: Switch role does not cause an error message in assignsubmission_comments
+
+  Background:
+    Given the following "courses" exist:
+      | fullname | shortname |
+      | Course 1 | C1        |
+    And the following "users" exist:
+      | username |
+      | teacher1 |
+    And the following "course enrolments" exist:
+      | course | user     | role           |
+      | C1     | teacher1 | editingteacher |
+    And I log in as "teacher1"
+    And I am on "Course 1" course homepage
+    And I turn editing mode on
+    And I add a "Assignment" to section "1" and I fill the form with:
+      | Assignment name           | Test assignment              |
+      | Description               | This is the description text |
+      | Students submit in groups | Yes                          |
+
+  Scenario: I switch role to student and an error doesn't occur
+    When I follow "Switch role to..." in the user menu
+    And I press "Student"
+    And I follow "Test assignment"
+    Then I should see "This is the description text"