def test_non_callable_text_func_raises_an_error(self):
with tempfile.TemporaryDirectory() as tmp_dir:
file = Path(tmp_dir, "foo.bar")
lines = sutils.write_to_file([], file, text_func=1)
self.assertRaises(TypeError, lambda: list(lines))
self.assertFalse(file.exists())
def test_iterable_is_written_to_file_when_processed(self):
with tempfile.TemporaryDirectory() as tmp_dir:
file = Path(tmp_dir, "foo.bar")
# call list to exhaust the iterable
list(sutils.write_to_file(["kissa"], file))
with file.open("r") as f:
self.assertEqual(["kissa"], f.readlines())
def test_file_exist_after_an_empty_list_is_processed(self):
with tempfile.TemporaryDirectory() as tmp_dir:
file = Path(tmp_dir, "foo.bar")
lines = sutils.write_to_file([], file)
self.assertEqual([], list(lines))
self.assertTrue(file.exists())
with file.open("r") as f:
self.assertEqual([], f.readlines())
def test_file_exists_in_case_text_func_fails(self):
with tempfile.TemporaryDirectory() as tmp_dir:
file = Path(tmp_dir, "foo.bar")
lines = sutils.write_to_file(["kissa"],
file,
text_func=lambda x, y: str(x + y))
self.assertRaises(TypeError, lambda: list(lines))
self.assertTrue(file.exists())
def test_existing_file_is_overwritten(self):
with tempfile.TemporaryDirectory() as tmp_dir:
file = Path(tmp_dir, "foo.bar")
with file.open("w") as f:
f.write("istuu")
list(sutils.write_to_file(["kissa"], file))
with file.open("r") as f:
self.assertEqual(["kissa"], f.readlines())
def test_text_func_does_not_change_output(self):
with tempfile.TemporaryDirectory() as tmp_dir:
file = Path(tmp_dir, "foo.bar")
xs = list(
sutils.write_to_file(["kissa"],
file,
text_func=lambda x: x[::-1]))
self.assertEqual(["kissa"], xs)
def test_text_func(self):
with tempfile.TemporaryDirectory() as tmp_dir:
file = Path(tmp_dir, "foo.bar")
list(
sutils.write_to_file(["kissa"],
file,
text_func=lambda x: x[::-1]))
with file.open("r") as f:
self.assertEqual(["assik"], f.readlines())
def test_readlines_returns_empty_list_after_partial_exhaustion(self):
# Note: OS differences make it difficult to test what happens
# when a file handle is being kept open in a generator. If this
# test fails on some platform, feel free to add a skip decorator
# (or write a better test!)
with tempfile.TemporaryDirectory() as tmp_dir:
file = Path(tmp_dir, "foo.bar")
xs = sutils.write_to_file(["kissa", "istuu"], file)
# advance the iterator by one
self.assertEqual("kissa", next(xs))
with file.open("r") as f:
self.assertEqual([], f.readlines())
# exhaust the iterator to avoid PermissionErrors on Windows when
# the tmp_dir context manager closes
list(xs)
def test_giving_a_folder_as_input_raises_error(self):
with tempfile.TemporaryDirectory() as tmp_dir:
file = Path(tmp_dir)
lines = sutils.write_to_file(["kissa"], file)
self.assertRaises(OSError, lambda: list(lines))
def test_writing_to_non_existing_folder_raises_exception(self):
with tempfile.TemporaryDirectory() as tmp_dir:
file = Path(tmp_dir, "baz", "foo.bar")
lines = sutils.write_to_file(["kissa"], file)
self.assertRaises(OSError, lambda: list(lines))
def test_write_to_file_does_not_add_newline_characters(self):
with tempfile.TemporaryDirectory() as tmp_dir:
file = Path(tmp_dir, "foo.bar")
list(sutils.write_to_file(["kissa", "istuu"], file))
with file.open("r") as f:
self.assertEqual(["kissaistuu"], f.readlines())
def test_file_is_not_written_until_iterable_is_processed(self):
with tempfile.TemporaryDirectory() as tmp_dir:
file = Path(tmp_dir, "foo.bar")
sutils.write_to_file(["kissa"], file)
self.assertFalse(file.exists())