yet another context fix for Roles tab - I hope this one is final; merged from MOODLE_...

diff --git a/user/tabs.php b/user/tabs.php
index 3bce70ab0fbad45c5a51166eaa80a208e49cf571..63ecfe4c4f92864b8bb6e7db7f8b1dc909a89def 100644 (file)
--- a/user/tabs.php
+++ b/user/tabs.php
@@ -182,21 +182,24 @@
 
     /// this needs permission checkings
 
-    $usercontext = get_context_instance(CONTEXT_USER, $user->id);
-    if (!empty($showroles) && has_capability('moodle/role:assign',$usercontext)) { // this variable controls whether this roles is showed, or not, so only user/view page should set this flag
-        $toprow[] = new tabobject('roles', $CFG->wwwroot.'/'.$CFG->admin.'/roles/assign.php?contextid='.$usercontext->id.'&userid='.$user->id.'&courseid='.$course->id
-                              ,get_string('roles'));
-                              
-        if (in_array($currenttab, array('assign', 'override'))) {
-            $inactive = array('roles');
-            $activetwo = array('roles');
-
-            $secondrow = array();
-            $secondrow[] = new tabobject('assign', $CFG->wwwroot.'/'.$CFG->admin.'/roles/assign.php?contextid='.$usercontext->id.'&userid='.$user->id.'&courseid='.$course->id
-                              ,get_string('assignroles', 'role'));
-            $secondrow[] = new tabobject('override', $CFG->wwwroot.'/'.$CFG->admin.'/roles/override.php?contextid='.$usercontext->id.'&userid='.$user->id.'&courseid='.$course->id
-                              ,get_string('overrideroles', 'role'));
-                                
+    
+    if (!empty($showroles) and !empty($user)) { // this variable controls whether this roles is showed, or not, so only user/view page should set this flag
+        $usercontext = get_context_instance(CONTEXT_USER, $user->id);
+        if (has_capability('moodle/role:assign',$usercontext)) {
+            $toprow[] = new tabobject('roles', $CFG->wwwroot.'/'.$CFG->admin.'/roles/assign.php?contextid='.$usercontext->id.'&userid='.$user->id.'&courseid='.$course->id
+                                  ,get_string('roles'));
+                                  
+            if (in_array($currenttab, array('assign', 'override'))) {
+                $inactive = array('roles');
+                $activetwo = array('roles');
+    
+                $secondrow = array();
+                $secondrow[] = new tabobject('assign', $CFG->wwwroot.'/'.$CFG->admin.'/roles/assign.php?contextid='.$usercontext->id.'&userid='.$user->id.'&courseid='.$course->id
+                                  ,get_string('assignroles', 'role'));
+                $secondrow[] = new tabobject('override', $CFG->wwwroot.'/'.$CFG->admin.'/roles/override.php?contextid='.$usercontext->id.'&userid='.$user->id.'&courseid='.$course->id
+                                  ,get_string('overrideroles', 'role'));
+                                    
+            }
         }                                                                                                       
     }
 /// Add second row to display if there is one