[FIX] base: translations lost after synchronization

Modifying a source term in an XML/HTML translated field can lose translations
if the same term is translated in several languages.

closes odoo/odoo#29082

2 files changed, 78 insertions, 53 deletions

diff --git a/odoo/addons/base/models/ir_translation.py b/odoo/addons/base/models/ir_translation.py
index a9ea0d5ae07..103f5a64675 100644
--- a/odoo/addons/base/models/ir_translation.py
+++ b/odoo/addons/base/models/ir_translation.py
@@ -457,15 +457,15 @@ class IrTranslation(models.Model):
         if not callable(field.translate):
             return
 
-        trans = self.env['ir.translation']
-        outdated = trans
-        discarded = trans
+        Translation = self.env['ir.translation']
+        outdated = Translation
+        discarded = Translation
 
         for record in records:
             # get field value and terms to translate
             value = record[field.name]
             terms = set(field.get_trans_terms(value))
-            record_trans = trans.search([
+            translations = Translation.search([
                 ('type', '=', 'model_terms'),
                 ('name', '=', "%s,%s" % (field.model_name, field.name)),
                 ('res_id', '=', record.id),
@@ -473,25 +473,32 @@ class IrTranslation(models.Model):
 
             if not terms:
                 # discard all translations for that field
-                discarded += record_trans
+                discarded += translations
                 continue
 
-            # remap existing translations on terms when possible
-            trans_src = record_trans.mapped('src')
-            for trans in record_trans:
-                if trans.src == trans.value:
-                    discarded += trans
-                elif trans.src not in terms:
-                    matches = get_close_matches(trans.src, terms, 1, 0.9)
-                    if matches:
-                        if matches[0] in trans_src:
-                            # there is already a translation for this term; discard this one
-                            discarded += trans
-                        else:
-                            trans.write({'src': matches[0], 'state': trans.state})
-                            trans_src.append(matches[0])  # avoid reuse of term
-                    else:
-                        outdated += trans
+            # remap existing translations on terms when possible; each term
+            # should be translated at most once per language
+            done = set()                # {(src, lang), ...}
+            translations_to_match = []
+
+            for translation in translations:
+                if not translation.value:
+                    discarded += translation
+                elif translation.src in terms:
+                    done.add((translation.src, translation.lang))
+                else:
+                    translations_to_match.append(translation)
+
+            for translation in translations_to_match:
+                matches = get_close_matches(translation.src, terms, 1, 0.9)
+                src = matches[0] if matches else None
+                if not src:
+                    outdated += translation
+                elif (src, translation.lang) in done:
+                    discarded += translation
+                else:
+                    translation.write({'src': src, 'state': translation.state})
+                    done.add((src, translation.lang))
 
         # process outdated and discarded translations
         outdated.write({'state': 'to_translate'})
diff --git a/odoo/addons/base/tests/test_translate.py b/odoo/addons/base/tests/test_translate.py
index 57081e6b1c7..c9d7f35ec4c 100644
--- a/odoo/addons/base/tests/test_translate.py
+++ b/odoo/addons/base/tests/test_translate.py
@@ -310,30 +310,36 @@ class TestTranslation(TransactionCase):
 class TestXMLTranslation(TransactionCase):
     def setUp(self):
         super(TestXMLTranslation, self).setUp()
-        self.env['ir.translation'].load_module_terms(['base'], ['fr_FR'])
+        self.env['ir.translation'].load_module_terms(['base'], ['fr_FR', 'nl_NL'])
+
+    def create_view(self, archf, terms, **kwargs):
+        view = self.env['ir.ui.view'].create({
+            'name': 'test',
+            'model': 'res.partner',
+            'arch': archf % terms,
+        })
+        for lang, trans_terms in kwargs.items():
+            for src, val in pycompat.izip(terms, trans_terms):
+                self.env['ir.translation'].create({
+                    'type': 'model_terms',
+                    'name': 'ir.ui.view,arch_db',
+                    'lang': lang,
+                    'res_id': view.id,
+                    'src': src,
+                    'value': val,
+                    'state': 'translated',
+                })
+        return view
 
     def test_copy(self):
         """ Create a simple view, fill in translations, and copy it. """
-        env_en = self.env(context={})
-        env_fr = self.env(context={'lang': 'fr_FR'})
-
         archf = '<form string="%s"><div>%s</div><div>%s</div></form>'
         terms_en = ('Knife', 'Fork', 'Spoon')
         terms_fr = ('Couteau', 'Fourchette', 'Cuiller')
-        view0 = self.env['ir.ui.view'].create({
-            'name': 'test',
-            'model': 'res.partner',
-            'arch': archf % terms_en,
-        })
-        for src, value in list(pycompat.izip(terms_en, terms_fr)):
-            self.env['ir.translation'].create({
-                'type': 'model_terms',
-                'name': 'ir.ui.view,arch_db',
-                'lang': 'fr_FR',
-                'res_id': view0.id,
-                'src': src,
-                'value': value,
-            })
+        view0 = self.create_view(archf, terms_en, fr_FR=terms_fr)
+
+        env_en = self.env(context={})
+        env_fr = self.env(context={'lang': 'fr_FR'})
 
         # check translated field
         self.assertEqual(view0.with_env(env_en).arch_db, archf % terms_en)
@@ -360,17 +366,29 @@ class TestXMLTranslation(TransactionCase):
         archf = '<form string="%s"><div>%s</div><div>%s</div></form>'
         terms_en = ('Knife', 'Fork', 'Spoon')
         terms_fr = (' Couteau', 'Fourchette ', ' Cuiller ')
-        view0 = self.env['ir.ui.view'].create({
-            'name': 'test',
-            'model': 'res.partner',
-            'arch': archf % terms_en,
-        })
-        for src, value in list(pycompat.izip(terms_en, terms_fr)):
-            self.env['ir.translation'].create({
-                'type': 'model_terms',
-                'name': 'ir.ui.view,arch_db',
-                'lang': 'fr_FR',
-                'res_id': view0.id,
-                'src': src,
-                'value': value,
-            })
+        self.create_view(archf, terms_en, fr_FR=terms_fr)
+
+    def test_sync(self):
+        """ Check translations after minor change in source terms. """
+        archf = '<form string="X">%s</form>'
+        terms_en = ('Bread and cheeze',)
+        terms_fr = ('Pain et fromage',)
+        terms_nl = ('Brood and kaas',)
+        view = self.create_view(archf, terms_en, fr_FR=terms_fr, nl_NL=terms_nl)
+
+        env_en = self.env(context={})
+        env_fr = self.env(context={'lang': 'fr_FR'})
+        env_nl = self.env(context={'lang': 'nl_NL'})
+
+        self.assertEqual(view.with_env(env_en).arch_db, archf % terms_en)
+        self.assertEqual(view.with_env(env_fr).arch_db, archf % terms_fr)
+        self.assertEqual(view.with_env(env_nl).arch_db, archf % terms_nl)
+
+        # modify source term in view (fixed type in 'cheeze')
+        terms_en = ('Bread and cheese',)
+        view.write({'arch_db': archf % terms_en})
+
+        # check whether translations have been synchronized
+        self.assertEqual(view.with_env(env_en).arch_db, archf % terms_en)
+        self.assertEqual(view.with_env(env_fr).arch_db, archf % terms_fr)
+        self.assertEqual(view.with_env(env_nl).arch_db, archf % terms_nl)