[FIX] web: deal with reference fields

The reference fields haven't been correctly implemented with the new views.
This commit restores their behaviour.

Note that an small improvement has been introduced in this commit.
Before saas-16, a `name_get` was done for each record (so 80 if the field
was displayed in a full list view), which is not optimal. The calls are now
batched by model (so one `name_get` by model appearing in the field values).

3 files changed, 105 insertions, 2 deletions

diff --git a/addons/web/static/src/js/fields/field_registry.js b/addons/web/static/src/js/fields/field_registry.js
index dcd8f7acd48..efafec6ba6a 100644
--- a/addons/web/static/src/js/fields/field_registry.js
+++ b/addons/web/static/src/js/fields/field_registry.js
@@ -64,6 +64,7 @@ registry
     .add('many2many_checkboxes', relational_fields.FieldMany2ManyCheckBoxes)
     .add('one2many', relational_fields.FieldOne2Many)
     .add('statusbar', relational_fields.FieldStatus)
+    .add('reference', relational_fields.FieldReference)
     .add('one2many_list', relational_fields.FieldOne2Many);
 
 // Special fields
diff --git a/addons/web/static/src/js/fields/field_utils.js b/addons/web/static/src/js/fields/field_utils.js
index 9a6734b7baf..becb1e124ef 100644
--- a/addons/web/static/src/js/fields/field_utils.js
+++ b/addons/web/static/src/js/fields/field_utils.js
@@ -494,7 +494,7 @@ return {
         many2one: formatMany2one,
         monetary: formatMonetary,
         one2many: formatX2Many,
-        reference: _.identity, // todo
+        reference: formatMany2one,
         selection: formatSelection,
         text: formatChar,
     },
@@ -512,7 +512,7 @@ return {
         many2one: parseMany2one,
         monetary: parseFloat,
         one2many: _.identity,
-        reference: _.identity, // todo
+        reference: parseMany2one,
         selection: _.identity, // todo
         text: _.identity, // todo
     },
diff --git a/addons/web/static/src/js/fields/relational_fields.js b/addons/web/static/src/js/fields/relational_fields.js
index 5b9114b6c82..44f884f130c 100644
--- a/addons/web/static/src/js/fields/relational_fields.js
+++ b/addons/web/static/src/js/fields/relational_fields.js
@@ -1943,6 +1943,106 @@ var FieldRadio = FieldSelection.extend({
     },
 });
 
+/**
+ * The FieldReference is a combination of a select (for the model) and
+ * a FieldMany2one for its value.
+ * Its intern representation is similar to the many2one (a datapoint with a
+ * `name_get` as data).
+ */
+var FieldReference = FieldMany2One.extend({
+    supportedFieldTypes: ['reference'],
+    template: 'FieldReference',
+    events: _.extend({}, FieldMany2One.prototype.events, {
+        'change select': '_onSelectionChange',
+    }),
+    /**
+     * @override
+     */
+    init: function () {
+        this._super.apply(this, arguments);
+
+        // needs to be copied as it is an unmutable object
+        this.field = _.extend({}, this.field);
+        if (this.value) {
+            this._setRelation(this.value.model);
+        }
+    },
+    /**
+     * @override
+     */
+    start: function () {
+        this.$('select').val(this.field.relation);
+        return this._super.apply(this, arguments);
+    },
+
+    //--------------------------------------------------------------------------
+    // Private
+    //--------------------------------------------------------------------------
+
+    /**
+     * Add a select in edit mode (for the model).
+     *
+     * @override
+     */
+    _renderEdit: function () {
+        this._super.apply(this, arguments);
+
+        if (this.$('select').val()) {
+            this.$('.o_input_dropdown').show();
+            this.$el.addClass('o_row'); // this class is used to display the two
+                                        // components (select & input) on the same line
+        } else {
+            // hide the many2one if the selection is empty
+            this.$('.o_input_dropdown').hide();
+        }
+
+    },
+    /**
+     * @override
+     * @private
+     */
+    _reset: function () {
+        this._super.apply(this, arguments);
+        this._setRelation(this.value && this.value.model);
+    },
+    /**
+     * Set `relation` key in field properties.
+     *
+     * @private
+     * @param {string} model
+     */
+    _setRelation: function (model) {
+        // used to generate the search in many2one
+        this.field.relation = model;
+    },
+    /**
+     * @override
+     * @private
+     */
+    _setValue: function (value, options) {
+        value = value || {};
+        // we need to specify the model for the change in basic_model
+        // the value is then now a dict with id, display_name and model
+        value.model = this.$('select').val();
+        return this._super(value, options);
+    },
+
+    //--------------------------------------------------------------------------
+    // Handlers
+    //--------------------------------------------------------------------------
+
+    /**
+     * When the selection (model) changes, the many2one is reset.
+     *
+     * @private
+     */
+    _onSelectionChange: function () {
+        var value = this.$('select').val();
+        this.reinitialize(false);
+        this._setRelation(value);
+    },
+});
+
 return {
     FieldMany2One: FieldMany2One,
     KanbanFieldMany2One: KanbanFieldMany2One,
@@ -1960,6 +2060,8 @@ return {
     FieldRadio: FieldRadio,
     FieldSelection: FieldSelection,
     FieldStatus: FieldStatus,
+
+    FieldReference: FieldReference,
 };
 
 });