[FIX] web: allow x2many fields without relation_field

Have a field x2many without relation_field.

Before this commit, a server error was raised because, we send changes
for the non-existing field (relation_field).

Now, we only send to the server the changes for relation_field only if
they exist.

Note that, this commit will also add an exception on the server mock
onchange if we sent changes for non-existings fields.

Part of task~3179751

Part-of: odoo/odoo#114024

addons/sale/static/tests/sale_product_field_tests.js

@@ -34,7 +34,13 @@ QUnit.module("Fields", (hooks) => {
                 },
                 'sale.order.line': {
                     fields: {
-                        product_template_id: { 
+                        order_id: {
+                            string: "Order Reference",
+                            type: "many2one",
+                            relation: "sale.order",
+                            relation_field: "order_line",
+                        },
+                        product_template_id: {
                             string: "Product",
                             type: "many2one",
                             relation: "product.template",

addons/web/static/src/model/relational_model/static_list.js

@@ -618,7 +618,7 @@ export class StaticList extends DataPoint {
 
     async _createNewRecordDatapoint(params = {}) {
         const changes = {};
-        if (!params.withoutParent) {
+        if (!params.withoutParent && this.config.relationField) {
             changes[this.config.relationField] = this._parent._getChanges();
             if (!this._parent.isNew) {
                 changes[this.config.relationField].id = this._parent.resId;

addons/web/static/tests/helpers/mock_server.js

@@ -936,6 +936,14 @@ export class MockServer {
 
         let serverValues = {};
         const onchangeValues = {};
+        for (const fieldName in changes) {
+            if (!(fieldName in this.models[modelName].fields)) {
+                throw makeServerError({
+                    type: "ValidationError",
+                    message: `Field ${fieldName} does not exist`,
+                });
+            }
+        }
         if (resId) {
             serverValues = this.mockRead(modelName, [args[0], fieldsFromView], kwargs)[0];
         } else if (firstOnChange) {

addons/web/static/tests/views/fields/one2many_field_tests.js

@@ -287,6 +287,30 @@ QUnit.module("Fields", (hooks) => {
         }
     );
 
+    QUnit.test("O2M field without relation_field", async function (assert) {
+        delete serverData.models.partner.fields.p.relation_field;
+
+        serverData.models.partner.records[0].p = [2, 4];
+        await makeView({
+            type: "form",
+            resModel: "partner",
+            serverData,
+            arch: `
+                <form>
+                    <field name="p">
+                        <tree>
+                            <field name="foo" invisible="1"/>
+                            <field name="display_name" />
+                        </tree>
+                    </field>
+                </form>`,
+            resId: 1,
+        });
+
+        await addRow(target, ".o_field_x2many_list");
+        assert.containsOnce(target, ".o_dialog");
+    });
+
     QUnit.test(
         "O2M List with pager, decoration and default_order: add and cancel adding",
         async function (assert) {
@@ -12807,7 +12831,10 @@ QUnit.module("Fields", (hooks) => {
 
         assert.strictEqual(target.querySelector("[name=int_field] input").value, "10");
         assert.containsN(target, ".o_data_row", 2);
-        assert.deepEqual(getNodesTextContent(target.querySelectorAll(".o_data_cell")), ["first record", "second record"]);
+        assert.deepEqual(getNodesTextContent(target.querySelectorAll(".o_data_cell")), [
+            "first record",
+            "second record",
+        ]);
         assert.strictEqual(
             target.querySelector(".o_x2m_control_panel .o_pager_counter").innerText,
             "1-2 / 3"
@@ -12816,7 +12843,10 @@ QUnit.module("Fields", (hooks) => {
         // trigger the onchange
         await editInput(target, "[name=int_field] input", "16");
         assert.containsN(target, ".o_data_row", 2);
-        assert.deepEqual(getNodesTextContent(target.querySelectorAll(".o_data_cell")), ["first record", "second record"]);
+        assert.deepEqual(getNodesTextContent(target.querySelectorAll(".o_data_cell")), [
+            "first record",
+            "second record",
+        ]);
         assert.containsNone(target, ".o_x2m_control_panel .o_pager");
     });