warning in the log for $data['below']

A couple of quick notes:

- This needs to be fixed in 8.x and then backported to 7.x
- When reporting a bug like this, please indicate what file & line the incriminating code lives in

That said, attached is a quick patch based on your post.

Version of the patch with a test away to try and work out why we book tests are failing

And again - this also tidys up the array structure as it was a mess.

We need !empty rather than isset. This will also improve performance a small amount as we will reduce calls on menu items that have no children but below set.

Alright, thank you. Looks like the tests are catching the problem and that the fix is working.

There is also a coding style clean-up included -- splitting the arrays on to multiple lines -- which is think is OK, here. If we do that, I have only this minor point: Maybe we should also add the usual trailing commas (),)?

A patch with that + a test only patch, again, would be awesome.

+++ b/core/modules/system/tests/menu.testundefined
@@ -979,21 +979,132 @@ class MenuTreeOutputTestCase extends DrupalWebTestCase {
+          )
+        )

Here.

+++ b/core/modules/system/tests/menu.testundefined
@@ -979,21 +979,132 @@ class MenuTreeOutputTestCase extends DrupalWebTestCase {
+              )
             )

Here.

+++ b/core/modules/system/tests/menu.testundefined
@@ -979,21 +979,132 @@ class MenuTreeOutputTestCase extends DrupalWebTestCase {
+                  )
+                )

Here.

+++ b/core/modules/system/tests/menu.testundefined
@@ -979,21 +979,132 @@ class MenuTreeOutputTestCase extends DrupalWebTestCase {
+                  )
+                )

Here.

+++ b/core/modules/system/tests/menu.testundefined
@@ -979,21 +979,132 @@ class MenuTreeOutputTestCase extends DrupalWebTestCase {
+          )
+        )
+      )

Here.

+++ b/core/modules/system/tests/menu.testundefined
@@ -979,21 +979,132 @@ class MenuTreeOutputTestCase extends DrupalWebTestCase {
+          )
+        )

Here.

+++ b/core/modules/system/tests/menu.testundefined
@@ -979,21 +979,132 @@ class MenuTreeOutputTestCase extends DrupalWebTestCase {
+          )
+        )

Here.

+++ b/core/modules/system/tests/menu.testundefined
@@ -979,21 +979,132 @@ class MenuTreeOutputTestCase extends DrupalWebTestCase {
+     'below' => array()

Here.

+++ b/core/modules/system/tests/menu.testundefined
@@ -979,21 +979,132 @@ class MenuTreeOutputTestCase extends DrupalWebTestCase {
           )
         )

Here, too.

+++ b/core/modules/system/tests/menu.testundefined
@@ -979,21 +979,132 @@ class MenuTreeOutputTestCase extends DrupalWebTestCase {
           )
         )

The test has not changed so there is no benefit what so ever in uploading it as a seperate patch again - we know that existing code fails. I re-roll this later with fixes above.

tagging

Looked for in D8 but cannot find either watchdog message nor similar code evidence.
Tested in D7 where the code is present. In unpatched state I cannot reproduce the error with multiple hierarchical menu entries. Are there special conditions involved?

Changing status

As part of the Bug smash initiative, we are triaging issues that are marked 'Postponed (maintainer needs more info)'. Based on the lack of additional information on this ticket, we believe this issue is no longer relevant so I am marking it 'Closed (outdated)'.