blocks: add support for post conditions (#71778)

tests/form_pages/test_block.py

@@ -2790,3 +2790,108 @@ def test_block_titles_and_empty_block_on_summary_page(pub, emails):
     assert 'Form Title' not in resp.text
     assert 'Form Page' not in emails.get('New form (form title)')['msg'].get_payload()[0].get_payload()
     assert 'Form Title' not in emails.get('New form (form title)')['msg'].get_payload()[0].get_payload()
+
+
+def test_block_field_post_condition(pub):
+    FormDef.wipe()
+    BlockDef.wipe()
+
+    block = BlockDef()
+    block.name = 'foobar'
+    block.fields = [
+        fields.StringField(id='123', label='Foo', varname='foo'),
+        fields.StringField(id='234', label='Bar', varname='bar'),
+    ]
+    block.post_conditions = [
+        {
+            'condition': {'type': 'django', 'value': 'block_var_foo|startswith:"b"'},
+            'error_message': 'foo must start with a b.',
+        },
+        {
+            'condition': {'type': 'django', 'value': 'block_var_foo == block_var_bar'},
+            'error_message': 'foo and bar must be identical.',
+        },
+    ]
+
+    block.store()
+
+    formdef = FormDef()
+    formdef.name = 'form title'
+    formdef.fields = [
+        fields.BlockField(id='1', label='test', block_slug='foobar'),
+    ]
+    formdef.store()
+
+    app = get_app(pub)
+    resp = app.get(formdef.get_url())
+    resp.form['f1$element0$f123'] = 'foo'
+    resp.form['f1$element0$f234'] = 'bar'
+    resp = resp.form.submit('submit')  # -> error
+    assert (
+        resp.pyquery('.widget-with-error .error').text()
+        == 'foo must start with a b. foo and bar must be identical.'
+    )
+
+    resp.form['f1$element0$f123'] = 'baz'
+    resp.form['f1$element0$f234'] = 'bar'
+    resp = resp.form.submit('submit')  # -> error
+    assert resp.pyquery('.widget-with-error .error').text() == 'foo and bar must be identical.'
+
+    resp.form['f1$element0$f123'] = 'baz'
+    resp.form['f1$element0$f234'] = 'baz'
+    resp = resp.form.submit('submit')  # -> validation page
+
+    assert resp.form['f1$element0$f123'].attrs['readonly']
+    resp = resp.form.submit('submit')  # -> end page
+
+    formdata = formdef.data_class().select()[0]
+    assert formdata.status == 'wf-new'
+    assert formdata.data == {
+        '1': {'data': [{'123': 'baz', '234': 'baz'}], 'schema': {'123': 'string', '234': 'string'}},
+        '1_display': 'foobar',
+    }
+
+    # multiple rows
+    formdef.fields[0].max_items = 3
+    formdef.store()
+    formdef.data_class().wipe()
+    resp = app.get(formdef.get_url())
+    resp.form['f1$element0$f123'] = 'baz'
+    resp.form['f1$element0$f234'] = 'bar'
+    resp = resp.form.submit('f1$add_element')
+    assert not resp.pyquery('.widget-with-error')
+
+    resp.form['f1$element1$f123'] = 'bar'
+    resp.form['f1$element1$f234'] = 'bar'
+    resp = resp.form.submit('submit')  # -> error
+    assert (
+        resp.pyquery('.widget-with-error[data-block-row="element0"] .error').text()
+        == 'foo and bar must be identical.'
+    )
+    assert resp.pyquery('.widget-with-error[data-block-row="element1"] .error').text() == ''
+
+    resp.form['f1$element1$f234'] = 'baz'
+    resp = resp.form.submit('submit')  # -> error
+    assert (
+        resp.pyquery('.widget-with-error[data-block-row="element0"] .error').text()
+        == 'foo and bar must be identical.'
+    )
+    assert (
+        resp.pyquery('.widget-with-error[data-block-row="element1"] .error').text()
+        == 'foo and bar must be identical.'
+    )
+
+    resp.form['f1$element0$f123'] = 'bar'
+    resp.form['f1$element1$f234'] = 'bar'
+    resp = resp.form.submit('submit')  # -> validation page
+    assert resp.form['f1$element0$f123'].attrs['readonly']
+    resp = resp.form.submit('submit')  # -> end page
+    formdata = formdef.data_class().select()[0]
+    assert formdata.status == 'wf-new'
+    assert formdata.data == {
+        '1': {
+            'data': [{'123': 'bar', '234': 'bar'}, {'123': 'bar', '234': 'bar'}],
+            'schema': {'123': 'string', '234': 'string'},
+        },
+        '1_display': 'foobar, foobar',
+    }

wcs/blocks.py

@@ -322,6 +322,8 @@ class BlockDef(StorableObject, PostConditionsXmlMixin):
         location = 'forms/blocks/%s/' % self.id
         for field in self.fields or []:
             yield from field.i18n_scan(base_location=location)
+        for post_condition in self.post_conditions or []:
+            yield location, None, post_condition.get('error_message')
 
     def get_all_fields(self):
         return self.fields
@@ -441,12 +443,13 @@ class BlockSubWidget(CompositeWidget):
             with self.block.visibility_context(value, self.index):
                 for i, post_condition in enumerate(self.block.post_conditions):
                     condition = post_condition.get('condition')
-                    error_message = post_condition.get('error_message')
                     try:
-                        if not conditions.Condition(condition, record_errors=False).evaluate():
-                            error_messages.append(error_message)
+                        if conditions.Condition(condition, record_errors=False).evaluate():
+                            continue
                     except RuntimeError:
-                        error_messages.append(error_message)
+                        pass
+                    error_message = post_condition.get('error_message')
+                    error_messages.append(get_publisher().translate(error_message))
             if error_messages:
                 self.set_error(' '.join(error_messages))