[Studio] Offer advanced relation fields for the Many-to-Many Relation data target

[alexbaat]

Bug

In the Studio Data Importer, fields of type Advanced Many-to-Many Relation and Advanced Many-to-Many Object Relation can never be selected as a mapping target. With a transformation result of dataObjectArray / assetArray the field select only lists the plain many-to-many fields — also when the data target type is Many-to-Many Relation, the one data target that writes advanced relations (ManyToManyRelation::getMergedDataArray() wraps the elements in ObjectMetadata / ElementMetadata).

Steps to reproduce

1. Have a class with an Advanced Many-to-Many Object Relation field.
2. In a Data Objects importer for that class, add a mapping whose pipeline results in dataObjectArray (e.g. Load Data Object → As Array).
3. In the advanced mapping modal, choose the data target type Many-to-Many Relation and open the field select: the advanced relation field is missing.

Cause

The backend supports it already: GET /data-importer/data-type/class-attributes accepts loadAdvancedRelations, and TransformationDataTypeService::getPimcoreDataTypes() then replaces dataObjectArray / assetArray with advancedDataObjectArray / advancedAssetArray, which include the advanced relation types. The Studio UI never sends the flag, and it keeps the loaded class attributes in a map keyed only by transformation result type, so the data target type never influences which fields are offered.

Fix

The attributes map key now also depends on the data target type:

• resolveAttrMapKey(transformationResultType, dataTargetType?) returns advancedRelations:<result type> for the manyToManyRelation data target with a dataObjectArray / assetArray result; every other combination keeps its existing key.
• parseAttrMapKey() turns a key back into the request parameters (transformationResultType + loadAdvancedRelations), so the mapping step loader and the modal's on-demand fetch (useAutoRecalculateType) request exactly what the key stands for.
• The consumers pass the data target type: useClassAttributes (field select in the modal), MappingItem (collapsed row title, now also part of the memo comparison) and the loader's watched key list, so switching a saved mapping's data target fetches the missing list.
• Autofill suggestions skip the advanced keys: they are not transformation result types, and autofill only creates direct mappings, which cannot write advanced relations.

The direct data target keeps offering the plain relation fields only, which is correct — Direct passes the raw elements to the setter, which an advanced relation does not accept.

Notes

• Source-only change: assets/studio has no jest/vitest setup, so there is no automated test to add; tsc --noEmit and ESLint pass. The built assets under src/Resources/public/studio/build/ are left to the automatic frontend build (the commit-build job is skipped for fork PRs).
• Applied to a 2026.2.4 installation and rebuilt; verified there that the backend returns the advanced relation field only with loadAdvancedRelations=true.
• Advanced relation metadata columns are still written empty (new ObjectMetadata($this->fieldName, [], $dataObject)); importing metadata values is out of scope here.

Tracking issue

Fixes pimcore/platform-version#536

🤖 Generated with Claude Code

[Copilot]

Copilot review overview

🟡 Changes recommended

Attribute caching is not class-scoped, allowing stale advanced fields after changing the resolver class.

Review effort: Balanced
Findings: 1

Open (1)

• Cache key omits selected class, exposing stale advanced fields · New

What changed in this PR

Enables advanced many-to-many relation fields as Studio mapping targets.

Changes:

• Adds target-aware attribute-map keys and request parsing.
• Fetches advanced relation attributes when required.
• Excludes advanced-only keys from direct-mapping autofill.

File	Description
types.ts	Adds advanced attribute-key helpers.
compute-autofill-suggestions.ts	Excludes advanced relation entries.
mapping-item.tsx	Resolves attributes using target type.
mapping-item-with-filter.tsx	Passes target type to mapping items.
use-mapping-step-loader.types.ts	Renames the watched-key result.
use-mapping-step-loader.tsx	Loads attributes using parsed map keys.
useClassAttributes.ts	Selects target-specific attributes.
use-auto-recalculate-type.ts	Fetches advanced attributes on demand.

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13 out of 14 committers have signed the CLA.
✅ (berfinyuksel)[https://github.com/berfinyuksel]
✅ (bluvulture)[https://github.com/bluvulture]
✅ (fashxp)[https://github.com/fashxp]
✅ (robertSt7)[https://github.com/robertSt7]
✅ (herbertroth)[https://github.com/herbertroth]
✅ (lukmzig)[https://github.com/lukmzig]
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✅ (ValeriaMaltseva)[https://github.com/ValeriaMaltseva]
✅ (martineiber)[https://github.com/martineiber]
✅ (ellenico77)[https://github.com/ellenico77]
✅ (alexbaat)[https://github.com/alexbaat]
❌ @JochenCal
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[pimcore-deployments]

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[jcPimcore]

Hello @alexbaat

Thanks for your contribution!

Since 2026.3 is released we do not maintain any 2026.2 version line anymore.
I rebased this PR onto 2026.3 now.

There is no todo coming with this on your side. Just an information.

Kind regards, Jochen