REST API supplier categories does not return all

[Heuser98]

#10778 Bug
In the REST API test section for retrieving categories of suppliers
https://xxx.xx/api/index.php/explorer/#!/thirdparties/thirdpartiesRetrieveSupplierCategories
you can see, that the API reteurns one category with the ID "2" in our example for the supplier with ID "74531". See attached scrennshot1.
Looking up the table "categorie_fournisseur" in the database of this installation you see, that the supplier with ID "74531" has 4 entries with the category IDs 2, 3, 6, 7. See attached scrennshot2.
According to table "categorie_fournisseur" in the database of this installation supplier "74375" has one category with ID "9". See attached screenshot2.
The REST API answer for this supplier is empty. See screenshot3.
The REST API answer for supplier 74349 is also empty. See screenshot4.

That shows, that the REST API ony returns the first row in table "categorie_fournisseur". All following rows are lost in the REST API answer.

Environment

• Version: 10.0.1
• Operating System: Linux h2web54 4.9.0-0.bpo.9-amd64 Develop #1 SMP Debian 4.9.168-1+deb9u3~deb8u1 (2019-06-17) x86_64
• Web Server: Apache
• PHP: 7.3.8
• Database: MySQL or MariaDB 5.7.26-log
• URL(s): https://xxx.xx/api/index.php/explorer/#!/thirdparties/thirdpartiesRetrieveSupplierCategories

Expected and actual behavior

The REST API answer should deliver all the categories of a supplier according to table "categorie_fournisseur" in the database. But it only delivers the categorie of the first row in table "categorie_fournisseur". All the other rows / categories of table "categorie_fournisseur" are ignored.

Steps to reproduce the behavior

• Add 2 or more categories in https://xxx.xx/categories/index.php?leftmenu=catfournish&type=1
• Assign these categories to supplier 1 and assign the second category in table "categorie_fournisseur" to supplier 2.
• retrieve the categories for supplier 1 and 2 from the REST API testpage https://xxx.xx/api/index.php/explorer/#!/thirdparties/thirdpartiesRetrieveSupplierCategories
• compare API answers with content of database table "categorie_fournisseur".

Attached files (Screenshots, screencasts, dolibarr.log, debugging informations…)

[Heuser98]

correction :

delete screenshots 3 and 4 in the previous post and use the new screenshots 5 and 6 attached here.

correction of actual behavior:

The API only delivers the first category of a third party listed in table "categorie_fournisseur". All the other categories listed for this user are ignored.

##New Atachements: