[FIX] survey: compute matrix answers display_name too

We here fix the `SurveyQuestionAnswer._compute_display_name`
method introduced in 55fa52be.

`survey.question.answers` used as matrix rows and columns
require different treatment as they are not used in triggers
but are both shown on the `survey.user.input.line` views,
where the display shouldn't change (nor cause a crash).

It also doesn't make much sense to create answers outside the
context of a question, so we remove the button that already
wasn't shown on the tree view.

As users may not fully upgrade their views or may wish to customize,
we add a fallback question title in `_compute_display_name`too.

Task-3495142

closes odoo/odoo#135853

Signed-off-by: Thibault Delavallee (tde) <tde@openerp.com>
Co-authored-by: Vivek Pathak <vivp@odoo.com>

addons/survey/models/survey_question.py

@@ -681,17 +681,19 @@ class SurveyQuestionAnswer(models.Model):
     is_correct = fields.Boolean('Correct')
     answer_score = fields.Float('Score', help="A positive score indicates a correct choice; a negative or null score indicates a wrong answer")
 
-    @api.depends('value', 'question_id.title')
+    @api.depends('value', 'question_id.question_type', 'question_id.title', 'matrix_question_id')
     def _compute_display_name(self):
-        """Render an answer name as "Question title : Answer value" making sure it is not too long.
+        """Render an answer name as "Question title : Answer value", making sure it is not too long.
 
-        This implementation makes sure we have at least 30 characters for the question title,
-        then we elide it, leaving the rest of the space for the answer.
+        Unless the answer is part of a matrix-type question, this implementation makes sure we have
+        at least 30 characters for the question title, then we elide it, leaving the rest of the
+        space for the answer.
         """
         for answer in self:
-            # _origin (or fallback title) is (likely temporarily) needed to support survey snapshot
-            # during onchange for a deleted answer used as trigger in another question.
-            title = answer._origin.question_id.title
+            if not answer.question_id or answer.question_id.question_type == 'matrix':
+                answer.display_name = answer.value
+                continue
+            title = answer.question_id.title or _("[Question Title]")
             n_extra_characters = len(title) + len(answer.value) + 3 - self.MAX_ANSWER_NAME_LENGTH  # 3 for `" : "`
             if n_extra_characters <= 0:
                 answer.display_name = f'{title} : {answer.value}'

addons/survey/tests/test_survey.py

@@ -429,38 +429,82 @@ class TestSurveyInternals(common.TestSurveyCommon, MailCase):
         )
         self.assertFalse(bool(get_question_by_title(cloned_survey, 'Q2').triggering_answer_ids))
 
+    @users('survey_manager')
+    def test_matrix_rows_display_name(self):
+        """Check that matrix rows' display name is not changed."""
+        # A case's shape is: (question title, row value, expected row display names)
+        cases = [
+            (
+                'Question 1',
+                'Row A is short, so what?',
+                'Row A is short, so what?',
+            ), (
+                'Question 2',
+                'Row B is a very long question, but it is shown by itself so there shouldn\'t be any change',
+                'Row B is a very long question, but it is shown by itself so there shouldn\'t be any change',
+            ),
+        ]
+
+        for question_title, row_value, exp_display_name in cases:
+            question = self.env['survey.question'].create({
+                'title': question_title,
+                'matrix_row_ids': [Command.create({'value': row_value})],
+            })
+
+            with self.subTest(question=question_title, row=row_value):
+                self.assertEqual(question.matrix_row_ids[0].display_name, exp_display_name)
+
     @users('survey_manager')
     def test_suggested_answer_display_name(self):
-        """Check that answers' display name is not too long and allows to identify the question & answer."""
-        # A case's shape is: (question_title, answer value, expected display name)
+        """Check that answers' display name is not too long and allows to identify the question & answer.
+
+        When a matrix answer though, simply show the value as the question and row should be made
+        clear via the survey.user.input.line context."""
+        # A case's shape is: (question title, answer value, expected display name, additional create values)
         cases = [
             (
                 'Question 1',
                 'Answer A is short',
                 'Question 1 : Answer A is short',
+                {}
             ), (
                 'Question 2',
                 'Answer B is a very long answer, so it should itself be shortened or we would go too far',
                 'Question 2 : Answer B is a very long answer, so it should itself be shortened or we...',
+                {}
             ), (
                 'Question 3 is a very long question, so what can we do?',
                 'Answer A is short',
                 'Question 3 is a very long question, so what can we do? : Answer A is short',
+                {}
             ), (
                 'Question 4 is a very long question, so what can we do?',
                 'Answer B is a bit too long for Q4 now',
                 'Question 4 is a very long question, so what can... : Answer B is a bit too long for Q4 now',
+                {}
             ), (
                 'Question 5 is a very long question, so what can we do?',
                 'Answer C is so long that both the question and the answer will be shortened',
                 'Question 5 is a very long... : Answer C is so long that both the question and the...',
+                {}
+            ), (
+                'Question 6',
+                'Answer A is short, so what?',
+                'Answer A is short, so what?',
+                {'question_type': 'matrix'},
+            ), (
+                'Question 7',
+                'Answer B is a very long answer, but it is shown by itself so there shouldn\'t be any change',
+                'Answer B is a very long answer, but it is shown by itself so there shouldn\'t be any change',
+                {'question_type': 'matrix'},
             ),
         ]
 
-        for question_title, answer_value, exp_display_name in cases:
+        for question_title, answer_value, exp_display_name, other_values in cases:
             question = self.env['survey.question'].create({
                 'title': question_title,
                 'suggested_answer_ids': [Command.create({'value': answer_value})],
+                **other_values
             })
 
             with self.subTest(question=question_title, answer=answer_value):

addons/survey/views/survey_question_views.xml

@@ -314,7 +314,7 @@
         <field name="name">survey.question.answer.view.form</field>
         <field name="model">survey.question.answer</field>
         <field name="arch" type="xml">
-            <form string="Question Answer Form">
+            <form string="Question Answer Form" create="False">
                 <sheet>
                     <field name="question_type" invisible="1"/>
                     <group>