[Python-Dev] [Csv] These csv test cases seem incorrect to me... (original) (raw)

John Machin sjmachin at lexicon.net
Mon Mar 12 04:09:05 CET 2007

On 12/03/2007 1:01 PM, skip at pobox.com wrote:

I decided it would be worthwhile to have a csv module written in Python (no C underpinnings) for a number of reasons:

* It will probably be easier to add Unicode support to a Python version * More people will be able to read/grok/modify/fix bugs in a Python implementation than in the current mixed Python/C implementation. * With alternative implementations of Python available (PyPy, IronPython, Jython) it makes sense to have a Python version they can use. I'm far from having anything which will pass the current test suite, but in diagnosing some of my current failures I noticed a couple test cases which seem wrong. In the TestDialectExcel class I see these two questionable tests: def testquotesandmore(self): self.readerAssertEqual('"a"b', [['ab']]) def testquoteandquote(self): self.readerAssertEqual('"a" "b"', [['a "b"']]) It seems to me that if a field starts with a quote it has to be a quoted field. Any quotes appearing within a quoted field have to be escaped and the field has to end with a quote. Both of these test cases fail on or the other assumption. If they are indeed both correct and I'm just looking at things crosseyed I think they at least deserve comments explaining why they are correct. Both test cases date from the first checkin. I performed the checkin because of the group developing the module I believe I was the only one with checkin privileges at the time, not because I wrote the test cases. Any ideas about why these test cases are in there? I can't imagine Excel generating either one.

Hi Skip,

'"a"b' can't be produced by applying minimalist CSV writing rules to 'ab'. A non-minimalist writer could produce '"ab"', but certainly not '"a"b'.

The second case is worse -- it's inconsistent; the reader is supposed to remove the quotes from "a" but not from "b"???

IMHO these test cases are WRONG and it's a worry that they "work" with the current csv module :-(

Regards,

John

More information about the Python-Dev mailing list