Support dynamic default time from another field

web_datetime_picker_default_time/static/src/js/datepicker.esm.js

@@ -2,7 +2,7 @@
 /* Copyright 2024 Camptocamp
  * License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl) */
 
-import {DatePicker, DateTimePicker} from "@web/core/datepicker/datepicker";
+import {DateTimePicker} from "@web/core/datepicker/datepicker";
 import {patch} from "@web/core/utils/patch";
 
 patch(DateTimePicker.prototype, "DateTimePickerDefaultTime", {
@@ -23,7 +23,7 @@ patch(DateTimePicker.prototype, "DateTimePickerDefaultTime", {
     },
 });
 
-DateTimePicker.props = _.extend({}, DatePicker.props, {
+DateTimePicker.props = _.extend({}, DateTimePicker.props, {
     defaultTime: {
         type: Object,
         shape: {

web_datetime_picker_default_time/static/src/js/datetime_field.esm.js

@@ -0,0 +1,42 @@
+/** @odoo-module **/
+/* Copyright 2024 Camptocamp
+ * License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl) */
+
+import {DateTimeField} from "@web/views/fields/datetime/datetime_field";
+import {patch} from "@web/core/utils/patch";
+
+patch(DateTimeField.prototype, "DateTimeFieldDefaultTime", {
+    get defaultTime() {
+        if (typeof this.props.defaultTime === "string") {
+            return this.props.record.data[this.props.defaultTime];
+        }
+        return this.props.defaultTime;
+    },
+});
+
+DateTimeField.props = _.extend({}, DateTimeField.props, {
+    defaultTime: {
+        type: [
+            String,
+            {
+                type: Object,
+                shape: {
+                    hour: Number,
+                    minute: Number,
+                    second: Number,
+                },
+                optional: true,
+            },
+        ],
+        optional: true,
+    },
+});
+
+const super_extractProps = DateTimeField.extractProps;
+
+DateTimeField.extractProps = ({attrs}) => {
+    return {
+        ...super_extractProps({attrs}),
+        defaultTime: attrs.options.defaultTime,
+    };
+};

web_datetime_picker_default_time/static/src/xml/datetime_field.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<templates xml:space="preserve">
+    <t t-inherit="web.DateTimeField" t-inherit-mode="extension" owl="1">
+        <xpath expr="//DateTimePicker" position="attributes">
+            <attribute name="defaultTime">defaultTime</attribute>
+        </xpath>
+    </t>
+</templates>