[FIX] web: editable list: shift-tab and readonly fields

Before this rev., navigating with shift-tab didn't produce the
expected result when there were readonly fields on the way. For
instance, pressing shift-tab on a field:
- to the right of a readonly field: the focus was kept in the
  current field, whereas it should have been moved to the first
  editable field to the left of the readonly one
- in the editable first cell of a row, with a readonly field in
  the last column: the focus was moved to the previous line,
  which is ok, but on the first editable cell of it, whereas it
  should have been on the last editable cell.

@KangOl this commit needs to be forwardported up to saas-12.2, not
later (the code slightly changed in saas-12.3, and we did another
version of the fix).

addons/web/static/src/js/views/list/list_editable_renderer.js

@@ -478,7 +478,8 @@ ListRenderer.include({
      */
     _moveToPreviousLine: function () {
         if (this.currentRow > 0) {
-            this._selectCell(this.currentRow - 1, this.columns.length - 1);
+            // FORWARD-PORT THIS COMMIT UP TO SAAS-12.2
+            this._selectCell(this.currentRow - 1, this.columns.length - 1, {inc: -1});
         } else {
             this.unselectRow().then(this.trigger_up.bind(this, 'add_record'));
         }
@@ -692,6 +693,8 @@ ListRenderer.include({
      * @param {boolean} [options.force=false] if true, force selecting the cell
      *   even if seems to be already the selected one (useful after a re-
      *   rendering, to reset the focus on the correct field)
+     * @param {integer} [options.inc=1] the increment to use when searching for
+     *   the "next" possible cell (if the cell to select can't be selected)
      * @return {Deferred} fails if no cell could be selected
      */
     _selectCell: function (rowIndex, fieldIndex, options) {
@@ -715,7 +718,7 @@ ListRenderer.include({
             var oldFieldIndex = self.currentFieldIndex;
             self.currentFieldIndex = fieldIndex;
             fieldIndex = self._activateFieldWidget(record, fieldIndex, {
-                inc: 1,
+                inc: options.inc || 1,
                 wrap: wrap,
                 event: options && options.event,
             });
@@ -868,7 +871,7 @@ ListRenderer.include({
         switch (ev.data.direction) {
             case 'previous':
                 if (this.currentFieldIndex > 0) {
-                    this._selectCell(this.currentRow, this.currentFieldIndex - 1, {wrap: false})
+                    this._selectCell(this.currentRow, this.currentFieldIndex - 1, {inc: -1, wrap: false})
                         .fail(this._moveToPreviousLine.bind(this));
                 } else {
                     this._moveToPreviousLine();

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

@@ -2859,6 +2859,87 @@ QUnit.module('Views', {
         list.destroy();
     });
 
+    QUnit.test('pressing SHIFT-TAB in editable list with a readonly field [REQUIRE FOCUS]', function (assert) {
+        assert.expect(4);
+
+        var list = createView({
+            View: ListView,
+            model: 'foo',
+            data: this.data,
+            arch: '<tree editable="bottom">' +
+                    '<field name="foo"/>' +
+                    '<field name="int_field" readonly="1"/>' +
+                    '<field name="qux"/>' +
+                '</tree>',
+        });
+
+        // start on 'qux', line 3
+        testUtils.dom.click(list.$('.o_data_row:nth(2) .o_data_cell:nth(2)'));
+        assert.hasClass(list.$('.o_data_row:nth(2)'), 'o_selected_row');
+        assert.strictEqual(document.activeElement, list.$('.o_data_row:nth(2) .o_data_cell input[name=qux]')[0]);
+
+        // Press 'shift-Tab' -> should go to first cell (same line)
+        $(document.activeElement).trigger({type: 'keydown', which: $.ui.keyCode.TAB, shiftKey: true});
+        assert.hasClass(list.$('.o_data_row:nth(2)'), 'o_selected_row');
+        assert.strictEqual(document.activeElement, list.$('.o_data_row:nth(2) .o_data_cell input[name=foo]')[0]);
+
+        list.destroy();
+    });
+
+    QUnit.test('pressing SHIFT-TAB in editable list with a readonly field in first column [REQUIRE FOCUS]', function (assert) {
+        assert.expect(4);
+
+        var list = createView({
+            View: ListView,
+            model: 'foo',
+            data: this.data,
+            arch: '<tree editable="bottom">' +
+                    '<field name="int_field" readonly="1"/>' +
+                    '<field name="foo"/>' +
+                    '<field name="qux"/>' +
+                '</tree>',
+        });
+
+        // start on 'foo', line 3
+        testUtils.dom.click(list.$('.o_data_row:nth(2) .o_data_cell:nth(1)'));
+        assert.hasClass(list.$('.o_data_row:nth(2)'), 'o_selected_row');
+        assert.strictEqual(document.activeElement, list.$('.o_data_row:nth(2) .o_data_cell input[name=foo]')[0]);
+
+        // Press 'shift-Tab' -> should go to previous line (last cell)
+        $(document.activeElement).trigger({type: 'keydown', which: $.ui.keyCode.TAB, shiftKey: true});
+        assert.hasClass(list.$('.o_data_row:nth(1)'), 'o_selected_row');
+        assert.strictEqual(document.activeElement, list.$('.o_data_row:nth(1) .o_data_cell input[name=qux]')[0]);
+
+        list.destroy();
+    });
+
+    QUnit.test('pressing SHIFT-TAB in editable list with a readonly field in last column [REQUIRE FOCUS]', function (assert) {
+        assert.expect(4);
+
+        var list = createView({
+            View: ListView,
+            model: 'foo',
+            data: this.data,
+            arch: '<tree editable="bottom">' +
+                    '<field name="int_field"/>' +
+                    '<field name="foo"/>' +
+                    '<field name="qux" readonly="1"/>' +
+                '</tree>',
+        });
+
+        // start on 'int_field', line 3
+        testUtils.dom.click(list.$('.o_data_row:nth(2) .o_data_cell:first'));
+        assert.hasClass(list.$('.o_data_row:nth(2)'), 'o_selected_row');
+        assert.strictEqual(document.activeElement, list.$('.o_data_row:nth(2) .o_data_cell input[name=int_field]')[0]);
+
+        // Press 'shift-Tab' -> should go to previous line ('foo' field)
+        $(document.activeElement).trigger({type: 'keydown', which: $.ui.keyCode.TAB, shiftKey: true});
+        assert.hasClass(list.$('.o_data_row:nth(1)'), 'o_selected_row');
+        assert.strictEqual(document.activeElement, list.$('.o_data_row:nth(1) .o_data_cell input[name=foo]')[0]);
+
+        list.destroy();
+    });
+
     QUnit.test('skip invisible fields when navigating list view with TAB', function (assert) {
         assert.expect(2);