From 90eac45ba9023f1971a156eb794fd7880cee31aa Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A9dric=20Krier?= <ced@b2ck.com>
Date: Thu, 8 Jun 2023 18:42:07 +0200
Subject: [PATCH] Skip child position of exported data based on field names

When exporting data of a xxx2Many field, the column to skip should be based on
the child field names instead of the exported value (which can be 0 for
example).

Closes #12316
(grafted from a91e1a9f95ca2b22d4ce5372b1753999d03aa8af)

--HG--
branch : 6.0
---
 trytond/trytond/model/modelstorage.py    |  9 +++++----
 trytond/trytond/tests/export_data.py     |  1 +
 trytond/trytond/tests/test_exportdata.py | 20 ++++++++++++++++++++
 3 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/trytond/trytond/model/modelstorage.py b/trytond/trytond/model/modelstorage.py
index ac1bffa98f..858f33c875 100644
--- a/trytond/trytond/model/modelstorage.py
+++ b/trytond/trytond/model/modelstorage.py
@@ -668,10 +668,11 @@ class ModelStorage(Model):
                         child_lines = ModelStorage.__export_row(child_record,
                                 child_fields_names)
                         if first:
-                            for child_fpos in range(len(fields_names)):
-                                if child_lines and child_lines[0][child_fpos]:
-                                    data[child_fpos] = \
-                                        child_lines[0][child_fpos]
+                            if child_lines:
+                                for child_fpos in range(len(fields_names)):
+                                    if child_fields_names[child_fpos]:
+                                        data[child_fpos] = (
+                                            child_lines[0][child_fpos])
                             lines += child_lines[1:]
                             first = False
                         else:
diff --git a/trytond/trytond/tests/export_data.py b/trytond/trytond/tests/export_data.py
index 67316f93b9..4194978303 100644
--- a/trytond/trytond/tests/export_data.py
+++ b/trytond/trytond/tests/export_data.py
@@ -9,6 +9,7 @@ class ExportDataTarget(ModelSQL):
     "Export Data Target"
     __name__ = 'test.export_data.target'
     name = fields.Char('Name')
+    value = fields.Float("Value")
 
 
 class ExportData(ModelSQL):
diff --git a/trytond/trytond/tests/test_exportdata.py b/trytond/trytond/tests/test_exportdata.py
index 3f6aa9deb4..01cfdf16c8 100644
--- a/trytond/trytond/tests/test_exportdata.py
+++ b/trytond/trytond/tests/test_exportdata.py
@@ -353,6 +353,26 @@ class ExportDataTestCase(unittest.TestCase):
                     'one2many/name']),
             [[export1.id, 'Target 1'], ['', 'Target 2'], [export2.id, '']])
 
+    @with_transaction()
+    def test_one2many_empty_value(self):
+        "Test export_data one2many with first child with 0 value"
+        pool = Pool()
+        ExportData = pool.get('test.export_data')
+        ExportDataTarget = pool.get('test.export_data.target')
+
+        export, = ExportData.create([{}])
+        ExportDataTarget.create([{
+                    'value': 0,
+                    'one2many': export.id,
+                    }, {
+                    'value': 42,
+                    'one2many': export.id,
+                    }])
+
+        self.assertEqual(
+            ExportData.export_data([export], ['id', 'one2many/value']),
+            [[export.id, 0], ['', 42]])
+
     @with_transaction()
     def test_reference(self):
         'Test export_data reference'