[FIX] account, point_of_sale: Fix complex taxes computation

The previous _compute_all wasn't able to get the right results in case of complex
taxes computation.

See tests for examples.

task: 39945

2 files changed, 64 insertions, 0 deletions

diff --git a/addons/account_tax_python/tests/__init__.py b/addons/account_tax_python/tests/__init__.py
new file mode 100644
index 00000000000..b9eada7706e
--- /dev/null
+++ b/addons/account_tax_python/tests/__init__.py
@@ -0,0 +1,3 @@
+# -*- coding: utf-8 -*-
+
+from . import test_tax
diff --git a/addons/account_tax_python/tests/test_tax.py b/addons/account_tax_python/tests/test_tax.py
new file mode 100644
index 00000000000..2ad4529cd4b
--- /dev/null
+++ b/addons/account_tax_python/tests/test_tax.py
@@ -0,0 +1,61 @@
+# -*- coding: utf-8 -*-
+from odoo.addons.account.tests.test_tax import TestTax
+from odoo.tests import tagged
+
+
+@tagged('post_install', '-at_install')
+class TestTaxPython(TestTax):
+
+    def setUp(self):
+        super(TestTaxPython, self).setUp()
+
+        self.python_tax = self.tax_model.create({
+            'name': 'Python TAx',
+            'amount_type': 'code',
+            'amount': 0.0,
+            'python_compute': 'result = ((price_unit * quantity) - ((price_unit * quantity) / 1.12)) * 0.5',
+            'sequence': 1,
+        })
+
+    def test_tax_python_basic(self):
+        res = self.python_tax.compute_all(130.0)
+        self._check_compute_all_results(
+            136.96, # 'total_included'
+            130.0,  # 'total_excluded'
+            [
+                # base , amount    | seq | amount | incl | incl_base
+                # --------------------------------------------------
+                (130.0, 6.96),   # |  1  |    6%  |   t  |
+                # --------------------------------------------------
+            ],
+            res
+        )
+
+    def test_tax_python_price_include(self):
+        self.python_tax.price_include = True
+        res = self.python_tax.compute_all(130.0)
+        self._check_compute_all_results(
+            130,    # 'total_included'
+            123.04, # 'total_excluded'
+            [
+                # base , amount     | seq | amount | incl | incl_base
+                # ---------------------------------------------------
+                (123.04, 6.96),   # |  1  |    6%  |   t  |
+                # ---------------------------------------------------
+            ],
+            res
+        )
+
+        res = (self.python_tax + self.python_tax).compute_all(130.0)
+        self._check_compute_all_results(
+            130,    # 'total_included'
+            116.07, # 'total_excluded'
+            [
+                # base , amount     | seq | amount | incl | incl_base
+                # ---------------------------------------------------
+                (116.07, 6.96),   # |  1  |    6%  |   t  |
+                (116.07, 6.97),   # |  1  |    6%  |   t  |
+                # ---------------------------------------------------
+            ],
+            res
+        )