bpo-35047, unittest.mock: Better error messages on assert_called_xxx failures (GH-10090)
unittest.mock now includes mock calls in exception messages if
assert_not_called, assert_called_once, or assert_called_once_with
fails.
diff --git a/Lib/unittest/mock.py b/Lib/unittest/mock.py
index 1a6c1a6..1977b87 100644
--- a/Lib/unittest/mock.py
+++ b/Lib/unittest/mock.py
@@ -30,6 +30,7 @@
import sys
import builtins
from types import ModuleType
+from unittest.util import safe_repr
from functools import wraps, partial
@@ -778,8 +779,10 @@
"""
self = _mock_self
if self.call_count != 0:
- msg = ("Expected '%s' to not have been called. Called %s times." %
- (self._mock_name or 'mock', self.call_count))
+ msg = ("Expected '%s' to not have been called. Called %s times.%s"
+ % (self._mock_name or 'mock',
+ self.call_count,
+ self._calls_repr()))
raise AssertionError(msg)
def assert_called(_mock_self):
@@ -796,8 +799,10 @@
"""
self = _mock_self
if not self.call_count == 1:
- msg = ("Expected '%s' to have been called once. Called %s times." %
- (self._mock_name or 'mock', self.call_count))
+ msg = ("Expected '%s' to have been called once. Called %s times.%s"
+ % (self._mock_name or 'mock',
+ self.call_count,
+ self._calls_repr()))
raise AssertionError(msg)
def assert_called_with(_mock_self, *args, **kwargs):
@@ -825,8 +830,10 @@
with the specified arguments."""
self = _mock_self
if not self.call_count == 1:
- msg = ("Expected '%s' to be called once. Called %s times." %
- (self._mock_name or 'mock', self.call_count))
+ msg = ("Expected '%s' to be called once. Called %s times.%s"
+ % (self._mock_name or 'mock',
+ self.call_count,
+ self._calls_repr()))
raise AssertionError(msg)
return self.assert_called_with(*args, **kwargs)
@@ -847,8 +854,8 @@
if not any_order:
if expected not in all_calls:
raise AssertionError(
- 'Calls not found.\nExpected: %r\n'
- 'Actual: %r' % (_CallList(calls), self.mock_calls)
+ 'Calls not found.\nExpected: %r%s'
+ % (_CallList(calls), self._calls_repr(prefix="Actual"))
) from cause
return
@@ -909,6 +916,19 @@
return klass(**kw)
+ def _calls_repr(self, prefix="Calls"):
+ """Renders self.mock_calls as a string.
+
+ Example: "\nCalls: [call(1), call(2)]."
+
+ If self.mock_calls is empty, an empty string is returned. The
+ output will be truncated if very long.
+ """
+ if not self.mock_calls:
+ return ""
+ return f"\n{prefix}: {safe_repr(self.mock_calls)}."
+
+
def _try_iter(obj):
if obj is None:
diff --git a/Lib/unittest/test/testmock/testmock.py b/Lib/unittest/test/testmock/testmock.py
index c7bfa27..8cd284a 100644
--- a/Lib/unittest/test/testmock/testmock.py
+++ b/Lib/unittest/test/testmock/testmock.py
@@ -1,4 +1,5 @@
import copy
+import re
import sys
import tempfile
@@ -407,6 +408,14 @@
lambda: mock.assert_called_once_with('bob', 'bar', baz=2)
)
+ def test_assert_called_once_with_call_list(self):
+ m = Mock()
+ m(1)
+ m(2)
+ self.assertRaisesRegex(AssertionError,
+ re.escape("Calls: [call(1), call(2)]"),
+ lambda: m.assert_called_once_with(2))
+
def test_assert_called_once_with_function_spec(self):
def f(a, b, c, d=None):
@@ -1250,6 +1259,13 @@
with self.assertRaises(AssertionError):
m.hello.assert_not_called()
+ def test_assert_not_called_message(self):
+ m = Mock()
+ m(1, 2)
+ self.assertRaisesRegex(AssertionError,
+ re.escape("Calls: [call(1, 2)]"),
+ m.assert_not_called)
+
def test_assert_called(self):
m = Mock()
with self.assertRaises(AssertionError):
@@ -1271,6 +1287,20 @@
with self.assertRaises(AssertionError):
m.hello.assert_called_once()
+ def test_assert_called_once_message(self):
+ m = Mock()
+ m(1, 2)
+ m(3)
+ self.assertRaisesRegex(AssertionError,
+ re.escape("Calls: [call(1, 2), call(3)]"),
+ m.assert_called_once)
+
+ def test_assert_called_once_message_not_called(self):
+ m = Mock()
+ with self.assertRaises(AssertionError) as e:
+ m.assert_called_once()
+ self.assertNotIn("Calls:", str(e.exception))
+
#Issue21256 printout of keyword args should be in deterministic order
def test_sorted_call_signature(self):
m = Mock()
diff --git a/Misc/ACKS b/Misc/ACKS
index 5014584..043d604 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -1570,6 +1570,7 @@
Michael Stone
Serhiy Storchaka
Ken Stox
+Petter Strandmark
Charalampos Stratakis
Dan Stromberg
Donald Stufft
diff --git a/Misc/NEWS.d/next/Library/2018-10-25-09-59-00.bpo-35047.abbaa.rst b/Misc/NEWS.d/next/Library/2018-10-25-09-59-00.bpo-35047.abbaa.rst
new file mode 100644
index 0000000..12eda27
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2018-10-25-09-59-00.bpo-35047.abbaa.rst
@@ -0,0 +1,3 @@
+``unittest.mock`` now includes mock calls in exception messages if
+``assert_not_called``, ``assert_called_once``, or ``assert_called_once_with``
+fails. Patch by Petter Strandmark.
\ No newline at end of file