[FIX] web: save changes when readonly if force_save is set

In previous versions, readonly used to prevent sending the values
of the fields to the server. However, it was not working properly
for fields which have their own sub-arch in the view, as the value
used to be sent regardless of the readonly value.

In the new views, the readonly modifier is never overlooked, which
created a bug in the stock_picking_return wizard which was not
able to return products received from a po anymore. Basically the
value of the product_id field was not sent so the create crashed.

This commit introduces a new "force_save" modifier which is used
to express that we want to save the value of the field even though
it is readonly from a user interface point of view.

addons/stock/wizard/stock_picking_return_views.xml

@@ -18,7 +18,7 @@
                 <group>
                     <field name="product_return_moves" nolabel="1">
                         <tree editable="top" create="0">
-                            <field name="product_id" readonly="1"/>
+                            <field name="product_id" readonly="1" force_save="1"/>
                             <field name="quantity"/>
                         </tree>
                     </field>

addons/web/static/src/js/views/basic/basic_model.js

@@ -2203,7 +2203,7 @@ var BasicModel = AbstractModel.extend({
             // remove readonly fields from the list of changes
             if (!withReadonly && fieldName in changes || fieldName in commands) {
                 var editionViewType = record._editionViewType[fieldName] || viewType;
-                if (this._isFieldReadonly(record, fieldName, editionViewType)) {
+                if (this._isFieldProtected(record, fieldName, editionViewType)) {
                     delete changes[fieldName];
                     continue;
                 }
@@ -2562,9 +2562,10 @@ var BasicModel = AbstractModel.extend({
         return context;
     },
     /**
-     * Returns true if the field is readonly (checking first in the modifiers,
-     * and if there is no readonly modifier, checking the readonly attribute of
-     * the field).
+     * Returns true if the field is protected against changes, looking for a
+     * readonly modifier unless there is a force_save modifier (checking first
+     * in the modifiers, and if there is no readonly modifier, checking the
+     * readonly attribute of the field).
      *
      * @private
      * @param {Object} record an element from the localData
@@ -2573,12 +2574,12 @@ var BasicModel = AbstractModel.extend({
      *   main viewType from the record
      * @returns {boolean}
      */
-    _isFieldReadonly: function (record, fieldName, viewType) {
+    _isFieldProtected: function (record, fieldName, viewType) {
         var fieldInfo = record.fieldsInfo[viewType || record.viewType][fieldName];
         if (fieldInfo) {
             var rawModifiers = JSON.parse(fieldInfo.modifiers || "{}");
             var modifiers = this._evalModifiers(record, rawModifiers);
-            return modifiers.readonly;
+            return modifiers.readonly && !fieldInfo.force_save;
         } else {
             return false;
         }

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

@@ -1475,6 +1475,71 @@ QUnit.module('Views', {
         model.destroy();
     });
 
+    QUnit.test('dont write on readonly fields unless save attribute is set', function (assert) {
+        assert.expect(6);
+
+        this.params.fieldNames = ['foo', 'bar'];
+        this.data.partner.onchanges.foo = function (obj) {
+            obj.bar = obj.foo.length;
+        };
+        this.params.fieldsInfo = {
+            default: {
+                foo: {},
+                bar: {
+                    modifiers:"{\"readonly\": true}",
+                    force_save: true,
+                },
+            }
+        };
+
+        var model = createModel({
+            Model: BasicModel,
+            data: this.data,
+            mockRPC: function (route, args) {
+                if (args.method === 'write') {
+                    assert.deepEqual(args.args[1], {bar: 14, foo: "verylongstring"},
+                        "should only save foo field");
+                }
+                if (args.method === 'create') {
+                    assert.deepEqual(args.args[0], {bar: 21, foo: "anotherverylongstring"},
+                        "should only save foo field");
+                }
+                return this._super(route, args);
+            },
+        });
+
+        model.load(this.params).then(function (resultID) {
+            var record = model.get(resultID);
+            assert.strictEqual(record.data.bar, 2,
+                "should be initialized with correct value");
+
+            model.notifyChanges(resultID, {foo: "verylongstring"});
+
+            record = model.get(resultID);
+            assert.strictEqual(record.data.bar, 14,
+                "should be changed with correct value");
+
+            model.save(resultID);
+        });
+
+        // start again, but with a new record
+        delete this.params.res_id;
+        model.load(this.params).then(function (resultID) {
+            var record = model.get(resultID);
+            assert.strictEqual(record.data.bar, 0,
+                "should be initialized with correct value (0 as integer)");
+
+            model.notifyChanges(resultID, {foo: "anotherverylongstring"});
+
+            record = model.get(resultID);
+            assert.strictEqual(record.data.bar, 21,
+                "should be changed with correct value");
+
+            model.save(resultID);
+        });
+        model.destroy();
+    });
+
     QUnit.test('default_get with one2many values', function (assert) {
         assert.expect(1);
 

odoo/addons/base/rng/view.rng

@@ -556,6 +556,7 @@
             <rng:optional><rng:attribute name="default_get"/></rng:optional>
             <rng:optional><rng:attribute name="required"/></rng:optional>
             <rng:optional><rng:attribute name="readonly"/></rng:optional>
+            <rng:optional><rng:attribute name="force_save"/></rng:optional>
             <rng:optional><rng:attribute name="view_mode"/></rng:optional>
             <rng:optional><rng:attribute name="widget"/></rng:optional>
             <rng:optional><rng:attribute name="context"/></rng:optional>