make_text_diff function and tests

make_text_diff() function will pick diff tuples (returned by MoinMoin/util/diff_datastruct.py) and will transform them to strings.
The text will be used for visualization of diffs in moin UI and in mail notifications about meta changes.

[Thomas.J.Waldmann, 2013-07-27 18:04:27]

https://codereview.appspot.com/11967043/diff/1/MoinMoin/util/_tests/test_diff...
File MoinMoin/util/_tests/test_diff_datastruct.py (right):

https://codereview.appspot.com/11967043/diff/1/MoinMoin/util/_tests/test_diff...
MoinMoin/util/_tests/test_diff_datastruct.py:108: for got, expected in
zip(make_text_diff(changes), results):
same mistake as last time.

why use zip when you can just have a list of (test input, expected test output)
tuples? just see my past test comments...

https://codereview.appspot.com/11967043/diff/1/MoinMoin/util/diff_datastruct.py
File MoinMoin/util/diff_datastruct.py (right):

https://codereview.appspot.com/11967043/diff/1/MoinMoin/util/diff_datastruct....
MoinMoin/util/diff_datastruct.py:94: ": " if keys else "", unicode(value))
looks ok

[ana.balica, 2013-07-27 18:13:09]

https://codereview.appspot.com/11967043/diff/1/MoinMoin/util/_tests/test_diff...
File MoinMoin/util/_tests/test_diff_datastruct.py (right):

https://codereview.appspot.com/11967043/diff/1/MoinMoin/util/_tests/test_diff...
MoinMoin/util/_tests/test_diff_datastruct.py:108: for got, expected in
zip(make_text_diff(changes), results):
On 2013/07/27 18:04:28, Thomas.J.Waldmann wrote:
> same mistake as last time.
> 
> why use zip when you can just have a list of (test input, expected test
output)
> tuples? just see my past test comments...

My reasoning was due to the complexity of the datastructure.
For some tests it becomes:
[((INSERT, ["key1", "key2"], 1), u"+ key1.key2: 1"), 
((DELETE, ["key1", "key2", "key3"], 2), u"- key1.key2.key3: 2")]

When we separate the args from results, it seems more readable.
Though if my rationale doesn't make sense, then change is not a problem of
course.

[Thomas.J.Waldmann, 2013-07-27 18:18:21]

I'ld change it. If you think one tuple is too much for one line, put the tuple
elements on 2 lines.

[ana.balica, 2013-07-27 19:16:15]

https://codereview.appspot.com/11967043/diff/9001/MoinMoin/util/_tests/test_d...
File MoinMoin/util/_tests/test_diff_datastruct.py (right):

https://codereview.appspot.com/11967043/diff/9001/MoinMoin/util/_tests/test_d...
MoinMoin/util/_tests/test_diff_datastruct.py:15: def _test_make_text_diff(self,
tests):
Decided to create an extra method, since those 3 lines were repeated 8 times.

[Thomas.J.Waldmann, 2013-07-27 19:25:11]

https://codereview.appspot.com/11967043/diff/9001/MoinMoin/util/_tests/test_d...
File MoinMoin/util/_tests/test_diff_datastruct.py (right):

https://codereview.appspot.com/11967043/diff/9001/MoinMoin/util/_tests/test_d...
MoinMoin/util/_tests/test_diff_datastruct.py:18: assert got == expected
make the assertion fail somehow - does one still see good enough, what test /
with what data is failing?

[ana.balica, 2013-07-27 19:59:43]

https://codereview.appspot.com/11967043/diff/9001/MoinMoin/util/_tests/test_d...
File MoinMoin/util/_tests/test_diff_datastruct.py (right):

https://codereview.appspot.com/11967043/diff/9001/MoinMoin/util/_tests/test_d...
MoinMoin/util/_tests/test_diff_datastruct.py:18: assert got == expected
On 2013/07/27 19:25:11, Thomas.J.Waldmann wrote:
> make the assertion fail somehow - does one still see good enough, what test /
> with what data is failing?

On fail one can see the values (got and expected) and also where the failing
comes from - the test function.

Sample output:
    def test_make_text_diff_float(self):
        tests = [([(INSERT, [], 1.2)], u"+1.2"),
                 ([(DELETE, [], 3.4)], u"- 3.4")]
^       self._test_make_text_diff(tests)
[...]
            for got in make_text_diff(changes):
^               assert got == expected
E               assert '+ 1.2' == u'+1.2'

^ equals >
What extra information it might require?