[IMP] web: add Registry predicate

Before this commit, any value could be added to registries and the class
needed to be overridden to assert that added values would answer to a
certain predicate.

Now, the registry can be instantiated with a given predicate function
that all added value must pass to be registered (default: all values
are accepted).

Existing implentations have been adapted:
- FieldRegistry
- FieldRegistryOwl.

addons/web/static/src/js/core/registry.js

@@ -20,13 +20,21 @@ odoo.define("web.Registry", function (require) {
      */
     class Registry {
         /**
-         * @param {Object} [mapping] the initial data in the registry
+         * @function predicate
+         * @param {any} value
+         * @returns {boolean}
          */
-        constructor(mapping) {
+        /**
+         * @param {Object} [mapping] the initial data in the registry
+         * @param {predicate} [predicate=(() => true)] predicate that each
+         *      added value must pass to be registered.
+         */
+        constructor(mapping, predicate = () => true) {
             this.map = Object.create(mapping || null);
             this._scoreMapping = Object.create(null);
             this._sortedKeys = null;
             this.listeners = []; // listening callbacks on newly added items.
+            this.predicate = predicate;
         }
 
         //--------------------------------------------------------------------------
@@ -42,6 +50,9 @@ odoo.define("web.Registry", function (require) {
          * @returns {Registry} can be used to chain add calls.
          */
         add(key, value, score) {
+            if (!this.predicate(value)) {
+                throw new Error(`Value of key "${key}" does not pass the addition predicate.`);
+            }
             this._scoreMapping[key] = score === undefined ? key : score;
             this._sortedKeys = null;
             this.map[key] = value;

addons/web/static/src/js/fields/field_registry.js

@@ -1,18 +1,12 @@
 odoo.define('web.field_registry', function (require) {
-"use strict";
+    "use strict";
 
-var Registry = require('web.Registry');
+    const Registry = require('web.Registry');
 
-var FieldRegistry = Registry.extend({
-    add: function (key, value, score) {
-        if (value.prototype instanceof owl.Component) {
-            throw new Error("This registry should not contain any Component. Use 'web.field_registry_owl' instead.");
-        }
-        return this._super(...arguments);
-    },
-});
-
-return new FieldRegistry();
+    return new Registry(
+        null,
+        (value) => !(value.prototype instanceof owl.Component)
+    );
 });
 
 odoo.define('web._field_registry', function (require) {

addons/web/static/src/js/fields/field_registry_owl.js

@@ -3,16 +3,10 @@ odoo.define('web.field_registry_owl', function (require) {
 
     const Registry = require('web.Registry');
 
-    const FieldRegistry = Registry.extend({
-        add: function (key, value, score) {
-            if (!(value.prototype instanceof owl.Component)) {
-                throw new Error("This registry should only contain subclasses of Component");
-            }
-            return this._super(...arguments);
-        },
-    });
-
-    return new FieldRegistry();
+    return new Registry(
+        null,
+        (value) => value.prototype instanceof owl.Component
+    );
 });
 
 odoo.define('web._field_registry_owl', function (require) {

addons/web/static/tests/core/registry_tests.js

@@ -70,6 +70,21 @@ QUnit.module('core', {}, function () {
         assert.deepEqual(registry.values(), ['bar', 'foo', 'qux']);
     });
 
+    QUnit.test("predicate prevents invalid values", function (assert) {
+        assert.expect(5);
+
+        const predicate = value => typeof value === "number";
+        const registry = new Registry(null, predicate);
+        registry.onAdd((key) => assert.step(key));
+
+        assert.ok(registry.add("age", 23));
+        assert.throws(
+            () => registry.add("name", "Fred"),
+            new Error(`Value of key "name" does not pass the addition predicate.`)
+        );
+        assert.deepEqual(registry.entries(), { age: 23 });
+        assert.verifySteps(["age"]);
+    });
 });
 
 });