RepeaterPageArray::applySortOrder() change-detection is token-unsafe — substring match on loadOrder skips legitimate updates (72be1bfd)

[adrianbj]

Short description of the issue

Commit 72be1bfd added a sort-order change detector in RepeaterPageArray and FieldtypeRepeater that uses strpos("$value", $loadOrder) === 0 against the PageArray's __toString form (id1|id2|...). Because it's a substring prefix check rather than a token comparison, it false-matches on digit-prefix collisions between IDs.

Expected behavior

In-place ID substitutions or reorderings that change the effective sort sequence cause applySortOrder() to run.

Actual behavior

wire/modules/Fieldtype/FieldtypeRepeater/RepeaterPageArray.php:206 and FieldtypeRepeater.module:1590:

$loadOrder = $value->finderOptions('loadOrder');
if($loadOrder && strpos("$value", $loadOrder) !== 0) {
    // ... applySortOrder ...
}

Failure cases:

• loadOrder = "1", current "10" → strpos === 0 → applySortOrder skipped (ID 1 replaced with ID 10 in a single-item list).
• loadOrder = "12|345", current "12|3456" → strpos === 0 → skipped (item 345 removed, item 3456 added in same slot).

Optional: Suggestion for a possible fix

Compare as tokens or use full-string equality:

$current = (string) $value;
if($loadOrder && $loadOrder !== $current) {
    // ... applySortOrder ...
}

Setup/Environment

• ProcessWire version: dev @ 15c749ed
• Files: wire/modules/Fieldtype/FieldtypeRepeater/RepeaterPageArray.php:206 and FieldtypeRepeater.module:1590
• Introduced in commit 72be1bfd