TreeCompare not ignoring whitespace

[John L. Clark]

I am interested in using TreeCompare (from 4Suite XML) for comparing
two XML trees, modulo whitespace differences. However, when I compare
the following two documents ('foo.xml' and 'foo.xml.2', respectively):

<foo>
<bar/></foo>

and

<foo>
<bar/>
</foo>

using `TreeCompare.TreeCompare(foo, foo2, ignoreWhitespace=True)`, I
get the following report of differences:

--- expected ---
#document
foo
node: <Element at 0xb79248ac: name u'foo', 0 attributes, 2 children>
node.childNodes:
[<Text at 0xb78773ec: u'\n '>,
<Element at 0xb792492c: name u'bar', 0 attributes, 0 children>]
--- compared ---
#document
foo
node: <Element at 0xb79249ac: name u'foo', 0 attributes, 3 children>
node.childNodes:
[<Text at 0xb787720c: u'\n '>,
<Element at 0xb79249ec: name u'bar', 0 attributes, 0 children>,
<Text at 0xb78771e4: u'\n'>]

Am I misinterpreting what the `ignoreWhitespace` parameter should do,
or is this a bug?

Take care,

John L. Clark

[Jeremy Kloth]

On Wednesday, June 11, 2008 7:19:25 am John L. Clark wrote:
> I am interested in using TreeCompare (from 4Suite XML) for comparing
> two XML trees, modulo whitespace differences.

Nice. Actual usage outside of the test suites!

You've encountered an under-implemented feature. ;) As implemented, it handled
differences in the *amount* of whitespace (read length > 0) between two
documents, not absence of it however. Attached is a patch that implements
the later behavior, as well.

Note, the fix is also available in the CCF branch hosted at hg.4suite.org.

Thanks,
Jeremy Kloth

[John L. Clark]

The fix is wrong. When it is supposed to filter out whitespace nodes,
it filters out all nodes except for non-whitespace text nodes:

+ children1 = [ c for c in children1
+ if c.nodeType == Node.TEXT_NODE
+ and not IsXmlSpace(c.data) ]

I have attached a Mercurial bundle with the fix from my repository.

Take care,

John L. Clark