Broken page list in "move page" and "select page" widgets (server error)

[fvsch]

Description

I’m testing an update of a 3.9 site to 4.0 and it looks like the page list widget used in a few places, namely in the "Move page" dialog and in the page selection widget of the Retour for Kirby plugin, breaks with a server error:

{
    "code": 500,
    "error": "array_merge(): Argument #3 must be of type array, bool given"
}

Some URLs for GET requests from the Panel that show this exact error:

• http://localhost:8000/panel/site/tree?parent=%2Fsite
• http://localhost:8000/panel/site/tree?move=%2Fpages%2Fcontact&parent=%2Fsite

Expected behavior

The request to /panel/site/tree doesn't fail.

Screenshots

To reproduce

I don't have steps to reproduce or a minimal reproduction yet.

I understand this is very little information to go with, and I suspect it's something in my setup (otherwise there would be issues for this filed already). I’m not confident I can make a simple repro through trial and error.

Any pointers on how I could investigate this?

I have 'debug' => true, 'whoops' => true in my config, but those Panel API requests don't show more information about where the issue occurred.

Your setup

Kirby Version

4.0.0

Console output
See above for the failing API request. There's another JS error after that, which I suspect comes from not handling the error response from the API when rendering the UI.

Your system (please complete the following information)

• Device: M1 Mac
• OS: macOS
• Browser: Chrome
• Version: 119

[fvsch]

Alright, I found the issue.

Using XDebug, I found where the error was generated:

kirby/src/Panel/Model.php

Lines 115 to 120 in 40eae8e

	// merge with defaults and blueprint option
	$settings = array_merge(
	$this->imageDefaults(),
	$settings ?? [],
	$this->model->blueprint()->image() ?? [],
	);

The issue was that I had one page blueprint (site/blueprints/pages/error.yml) which had image: false at the root:

title: Error page
image: false

sections:
  fields:
    # …

This faulty value (probably the result of writing blueprints through a lot of trial and error ^^) gets returned as-is by $this->model->blueprint()->image(), and since false ?? [] is false, we end up with a PHP error.

So this is definitely my fault and not a bug per se, but this was very hard to identify. Could something be improved here?

There is some blueprint data normalization going on here, maybe there should be more?

kirby/src/Cms/Blueprint.php

Lines 74 to 84 in 40eae8e

	// normalize and translate the title
	$props['title'] ??= ucfirst($props['name']);
	$props['title'] = $this->i18n($props['title']);
	// convert all shortcuts
	$props = $this->convertFieldsToSections('main', $props);
	$props = $this->convertSectionsToColumns('main', $props);
	$props = $this->convertColumnsToTabs('main', $props);
	// normalize all tabs
	$props['tabs'] = $this->normalizeTabs($props['tabs'] ?? []);

[fvsch]

By the way I checked the cookbook (because earlier in the year I had copied page blueprint examples from the cookbook that were triggering bugs in Kirby 3.9, so I was wondering if that was from a faulty example). Couldn't find an instance of image: false for a page blueprint. So it's probably just my mistake.

[distantnative]

Will need look into this as these lines

kirby/src/Panel/Model.php

Lines 101 to 104 in 40eae8e

	// completely switched off
	if ($settings === false) {
	return null;
	}

should in theory cover the case you describe.

[distantnative]

Got it, it's not the $settings one but the third argument.