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self.assertEqual(response.content.decode(), expected_html)
AssertionError: '<!DO[596 chars] <input class="form-control input-lg"
id="[342 chars]l>\n' != '<!DO[596 chars] \n \n
[233 chars]l>\n'
That error message is impossible to read though. Let’s clarify its message a little:
lists/tests/test_views.py (ch11l016).
class
HomePageTest
(
TestCase
):
maxDiff
=
None
#
[
...
]
def
test_home_page_returns_correct_html
(
self
):
request
=
HttpRequest
()
response
=
home_page
(
request
)
expected_html
=
render_to_string
(
'home.html'
)
self
.
assertMultiLineEqual
(
response
.
content
.
decode
(),
expected_html
)
#
assertMultiLineEqual
is useful for comparing long strings; it gives you a diff-
style output, but it truncates long diffs by default…
…so that’s why we also need to set
maxDiff = None
on the test class.
Sure enough, it’s because our
render_to_string
call doesn’t know about the form:
[...]
<form method="POST" action="/lists/new">
- <input class="form-control input-lg" id="id_text"
name="text" placeholder="Enter a to-do item" type="text" />
+
[...]
But we can fix that:
lists/tests/test_views.py.
def
test_home_page_returns_correct_html
(
self
):
request
=
HttpRequest
()
response
=
home_page
(
request
)
expected_html
=
render_to_string
(
'home.html'
, {
'form'
:
ItemForm
()})
self
.
assertMultiLineEqual
(
response
.
content
.
decode
(),
expected_html
)
And that gets us back to passing. We’ve now reassured ourselves enough that the be‐
haviour has stayed the same, so it’s now OK to delete the two old tests. The
assertTem
plateUsed
and
response.context
checks from the new test are sufficient for testing a
basic view with a GET request.
That leaves us with just two tests in
HomePageTest
:
lists/tests/test_views.py (ch11l017).
class
HomePageTest
(
TestCase
):
def
test_home_page_renders_home_template
(
self
):
[
...
]
def
test_home_page_uses_item_form
(
self
):
[
...
]
200
|
Chapter 11: A Simple Form