[FIX] web: custom filter on date[time] with changing the operator

On a list view, Add a custom filter on a date
Change the operator to "in between"
Change it back to "equal"
Apply the search

Before this commit, the label of the filter still was in between
Whereas it should have been "equal to ..."

After this commit, the label of the filter is correct

OPW 2085951

closes odoo/odoo#38705

Signed-off-by: Lucas Perais (lpe) <lpe@odoo.com>

addons/web/static/src/js/views/search/search_filters.js

@@ -242,7 +242,8 @@ var DateTime = Field.extend({
     },
     toString: function () {
         var str = field_utils.format[this.attributes.type](this.get_value(), {type: this.attributes.type});
-        var date_1_value = this.datewidget_1 && this.get_value(1);
+        // the second datewidget might have been hidden because the operator has changed
+        var date_1_value = this.datewidget_1 && !this.datewidget_1.$el.hasClass('o_hidden') && this.get_value(1);
         if (date_1_value) {
             str += _lt(" and ") + field_utils.format[this.attributes.type](date_1_value, {type: this.attributes.type});
         }

addons/web/static/tests/views/search_view_tests.js

@@ -686,7 +686,7 @@ QUnit.module('Search View', {
         actionManager.destroy();
     });
 
-    QUnit.test('Custom Filter datetime with equal operator', function (assert) {
+    QUnit.test('Custom Filter datetime with equal operator, operator has been changed', function (assert) {
         assert.expect(5);
 
         this.data.partner.fields.date_time_field = {string: "DateTime", type: "datetime", store: true, searchable: true};
@@ -724,6 +724,14 @@ QUnit.module('Search View', {
         assert.strictEqual($('.o_dropdown_menu select.o_searchview_extended_prop_op').val(), '=',
             'The equal operator is selected');
 
+        // Change operator, and back
+        $('.o_dropdown_menu select.o_searchview_extended_prop_op').val('between').trigger('change');
+
+        assert.strictEqual($('.o_dropdown_menu select.o_searchview_extended_prop_op').val(), 'between',
+            'The between operator is selected');
+
+        $('.o_dropdown_menu select.o_searchview_extended_prop_op').val('=').trigger('change');
+
         $('.o_searchview_extended_prop_value input').val('02/22/2017 11:00:00').trigger('change'); // in TZ
 
         searchReadCount = 1;