Merge pull request #839 from georgeyk/refactor-xargs-partition

Update xargs.partition with platform information

tests/xargs_test.py

@@ -1,11 +1,39 @@
+# -*- coding: utf-8 -*-
 from __future__ import absolute_import
 from __future__ import unicode_literals
 
+import sys
+
+import mock
 import pytest
+import six
 
 from pre_commit import xargs
 
 
+@pytest.fixture
+def win32_py2_mock():
+    with mock.patch.object(sys, 'getfilesystemencoding', return_value='utf-8'):
+        with mock.patch.object(sys, 'platform', 'win32'):
+            with mock.patch.object(six, 'PY2', True):
+                yield
+
+
+@pytest.fixture
+def win32_py3_mock():
+    with mock.patch.object(sys, 'getfilesystemencoding', return_value='utf-8'):
+        with mock.patch.object(sys, 'platform', 'win32'):
+            with mock.patch.object(six, 'PY2', False):
+                yield
+
+
+@pytest.fixture
+def linux_mock():
+    with mock.patch.object(sys, 'getfilesystemencoding', return_value='utf-8'):
+        with mock.patch.object(sys, 'platform', 'linux'):
+            yield
+
+
 def test_partition_trivial():
     assert xargs.partition(('cmd',), ()) == (('cmd',),)
 
@@ -35,6 +63,35 @@ def test_partition_limits():
     )
 
 
+def test_partition_limit_win32_py3(win32_py3_mock):
+    cmd = ('ninechars',)
+    # counted as half because of utf-16 encode
+    varargs = ('😑' * 5,)
+    ret = xargs.partition(cmd, varargs, _max_length=20)
+    assert ret == (cmd + varargs,)
+
+
+def test_partition_limit_win32_py2(win32_py2_mock):
+    cmd = ('ninechars',)
+    varargs = ('😑' * 5,)  # 4 bytes * 5
+    ret = xargs.partition(cmd, varargs, _max_length=30)
+    assert ret == (cmd + varargs,)
+
+
+def test_partition_limit_linux(linux_mock):
+    cmd = ('ninechars',)
+    varargs = ('😑' * 5,)
+    ret = xargs.partition(cmd, varargs, _max_length=30)
+    assert ret == (cmd + varargs,)
+
+
+def test_argument_too_long_with_large_unicode(linux_mock):
+    cmd = ('ninechars',)
+    varargs = ('😑' * 10,)  # 4 bytes * 10
+    with pytest.raises(xargs.ArgumentTooLongError):
+        xargs.partition(cmd, varargs, _max_length=20)
+
+
 def test_argument_too_long():
     with pytest.raises(xargs.ArgumentTooLongError):
         xargs.partition(('a' * 5,), ('a' * 5,), _max_length=10)