Keep collection properties dirty-checked after reassignment; track iterator-based removals

[codeconsole]

Mongo Collection Property Dirty Tracking

On interception-based stores (MongoDB), two everyday mutation patterns silently escape dirty checking — save() reports success and persists nothing:

// 1. The defensive re-init — true for an EMPTY tracked list, because empty collections are falsy
if (!schedule.shares) {
    schedule.shares = []              // replaces the tracked wrapper with a plain ArrayList
}                                     // and [] == [] means the assignment isn't even flagged
schedule.shares.add(newShare)         // invisible: plain list, nothing marks the entity dirty
schedule.save(flush: true)            // writes nothing

// 2. Groovy's closure-based removal — removes via iterator().remove()
schedule.shares.removeAll { it.userId == userId }   // DirtyCheckingCollection doesn't override iterator()
schedule.save(flush: true)                          // writes nothing

Hibernate is unaffected — its flush-time snapshot comparison catches everything. Mongo relies exclusively on the DirtyChecking* wrappers, so anything that escapes them is lost. Hit in production: a schedule-sharing feature showed "shared" while the document kept shares: [].

The fix (interception only — no snapshots, no flush-time diffing)

1. Wrappers track every mutation path. iterator()/listIterator() now return dirty-marking iterators (covers removeAll(Closure), retainAll(Closure), removeIf), plus the missing direct overrides: retainAll(Collection), List.sort, List.replaceAll. Same approach as Hibernate's PersistentCollection.

2. Generated setters keep tracking across reassignment. Collection/List/Set/Map-typed properties assign through DirtyCheckingSupport.rewrap:

// generated setter, before:
void setShares(List shares) { markDirty("shares", shares); this.shares = shares }
// after:
void setShares(List shares) { markDirty("shares", shares); this.shares = (List) DirtyCheckingSupport.rewrap(this, "shares", this.shares, shares) }

rewrap wraps the new value only when the value being replaced was itself a tracked wrapper — otherwise it returns the raw value after one instanceof. Never-tracked properties (transient instances, Hibernate entities) behave exactly as before, and non-collection properties compile to identical bytecode.

3. Replacement wrappers are flagged isAssigned() (default method on DirtyCheckableCollection, so binary-compatible). PersistentEntityCodec then takes the full-rewrite path instead of per-element diffing — a replacement's layout need not match the stored array. Without the flag, a same-size replacement holding clean elements emitted no update at all.

Tests

Each escape is reproduced by a spec that fails without the fix:

• DirtyCheckingCollectionSpec — 8 wrapper mutation paths that bypassed tracking
• DirtyCheckCollectionReassignmentSpec — reassignment loses tracking (List/Set/Map); never-tracked values stay untouched
• EmbeddedCollectionDirtyTrackingSpec — end-to-end against MongoDB, replicating the production shape (an auto-timestamped entity: the lastUpdated write during flush resets the explicit-save dirty marker, so persistence depends entirely on the wrappers)

[codecov]

Codecov Report

❌ Patch coverage is 95.23810% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 54.7809%. Comparing base (c1b532a) to head (708aa2e).

Files with missing lines	Patch %	Lines
...ping/dirty/checking/DirtyCheckingCollection.groovy	88.2353%	2 Missing ⚠️
...re/mapping/dirty/checking/DirtyCheckingList.groovy	96.4286%	1 Missing ⚠️
...pping/dirty/checking/DirtyCheckingSortedSet.groovy	75.0000%	1 Missing ⚠️

Additional details and impacted files

@@                Coverage Diff                 @@
##                8.0.x     #16282        +/-   ##
==================================================
+ Coverage     54.7365%   54.7809%   +0.0444%     
- Complexity      20470      20507        +37     
==================================================
  Files            2103       2104         +1     
  Lines          101077     101152        +75     
  Branches        17928      17935         +7     
==================================================
+ Hits            55326      55412        +86     
+ Misses          37876      37862        -14     
- Partials         7875       7878         +3     

Files with missing lines	Coverage Δ
...g/mongo/engine/codecs/PersistentEntityCodec.groovy	73.8872% <100.0000%> (+0.0777%)	⬆️
...ails/compiler/gorm/DirtyCheckingTransformer.groovy	78.9720% <100.0000%> (+0.8166%)	⬆️
...pping/dirty/checking/DirtyCheckableCollection.java	100.0000% <100.0000%> (ø)
...ore/mapping/dirty/checking/DirtyCheckingMap.groovy	50.0000% <100.0000%> (+10.0000%)	⬆️
...ore/mapping/dirty/checking/DirtyCheckingSet.groovy	100.0000% <100.0000%> (ø)
...mapping/dirty/checking/DirtyCheckingSupport.groovy	78.4314% <100.0000%> (+7.3787%)	⬆️
...re/mapping/dirty/checking/DirtyCheckingList.groovy	79.4872% <96.4286%> (+37.8205%)	⬆️
...pping/dirty/checking/DirtyCheckingSortedSet.groovy	83.3333% <75.0000%> (+83.3333%)	⬆️
...ping/dirty/checking/DirtyCheckingCollection.groovy	75.6757% <88.2353%> (+16.5848%)	⬆️

... and 1 file with indirect coverage changes

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[testlens-app]

✅ All tests passed ✅

🏷️ Commit: 708aa2e
▶️ Tests: 18960 executed
⚪️ Checks: 89/89 completed

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