[ADD] base: new wizard to uninstall a module (#17284)

The "Uninstall" button on the module form no longer changes the state of
modules, so that cancelling the wizard will not unexpectedly perform the
uninstallation.  The uninstallation is performed only by clicking on the
"Confirm" button on the wizard.

Moreover, the wizard provides clearer information about the impact of the
uninstallation: what apps/modules will be uninstalled and what documents
(models) will be lost.

1 files changed, 55 insertions, 0 deletions

diff --git a/odoo/addons/base/module/wizard/base_module_uninstall.py b/odoo/addons/base/module/wizard/base_module_uninstall.py
new file mode 100644
index 00000000000..1168e57341c
--- /dev/null
+++ b/odoo/addons/base/module/wizard/base_module_uninstall.py
@@ -0,0 +1,55 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo import api, fields, models
+
+
+class BaseModuleUninstall(models.TransientModel):
+    _name = "base.module.uninstall"
+    _description = "Module Uninstallation"
+
+    show_all = fields.Boolean()
+    module_id = fields.Many2one('ir.module.module', string="Module", required=True,
+                                domain=[('state', 'in', ['installed', 'to upgrade', 'to install'])])
+    module_ids = fields.Many2many('ir.module.module', string="Impacted modules",
+                                  compute='_compute_module_ids')
+    model_ids = fields.Many2many('ir.model', string="Impacted data models",
+                                 compute='_compute_model_ids')
+
+    def _get_modules(self):
+        """ Return all the modules impacted by self. """
+        return self.module_id.downstream_dependencies(self.module_id)
+
+    @api.depends('module_id', 'show_all')
+    def _compute_module_ids(self):
+        for wizard in self:
+            modules = wizard._get_modules()
+            wizard.module_ids = modules if wizard.show_all else modules.filtered('application')
+
+    def _get_models(self):
+        """ Return the models (ir.model) to consider for the impact. """
+        return self.env['ir.model'].search([('transient', '=', False)])
+
+    @api.depends('module_ids')
+    def _compute_model_ids(self):
+        ir_models = self._get_models()
+        ir_models_xids = ir_models._get_external_ids()
+        for wizard in self:
+            if wizard.module_id:
+                module_names = set(wizard._get_modules().mapped('name'))
+                # find the models that have all their XIDs in the given modules
+                def lost(model):
+                    return all(xid.split('.')[0] in module_names
+                               for xid in ir_models_xids.get(model.id, ()))
+                self.model_ids = ir_models.filtered(lost).sorted('name')
+
+    @api.onchange('module_id')
+    def _onchange_module_id(self):
+        # if we select a technical module, show technical modules by default
+        if not self.module_id.application:
+            self.show_all = True
+
+    @api.multi
+    def action_uninstall(self):
+        modules = self.mapped('module_id')
+        return modules.button_immediate_uninstall()