rgheck schreef:
rgheck wrote:
Vincent van Ravesteijn wrote:
That said, QFileInfo already caches this data. So why wasn't that
good enough? Why did Bennett have the problem that required the
refresh() calls that lead to the additional filesystem access? I
think the answer is that the first time the comparison was made,
the file didn't exist, and THAT fact got cached, so that the next
time the comparison was made, it returned false, even though the
filenames were the same. (This is the odd behavior of QFileInfo
that Vincent ran into somewhere else.) So we had to refresh. I
think this case is dealt with properly here. If we get nothing back
from canonicalFilename(), then we just compare the paths.
Yes, something like this happens indeed. Note further that the
caching of QFileInfo only makes sense if you access the same object.
In e.g. filetools.cpp:makeAbsPath() we make a new filename object
every time, which thus has a new QFileInfo object, which
automatically doesn't know about any cached values. This means that
if we keep the user defined path in e.g. InsetInclude, we create the
absolute path every time when we want to compare this value with the
one in theBufferList().
One more idea. Looking back at this thread, you once noted, Vincent,
that it's the check of QFileInfo::exists() that accesses the
filesystem in the constructor. What if we just take this out? Then
QFileInfo's own cache will deal with the makeAbsPath problem for us.
Presumably we then have a different problem, but maybe we can deal
with it some other way. But surely it's crazy to access the filesystem
every time we create a FileName object.
Yes, that looks like a sensible plan, but.. now we have to find out
which other problems are introduced.. I don't know whether that will be
easy.
What do you mean by the makeAbsPath problem ? The problem is that we are
comparing a different FileName object each time, so caching won't help
us out here. We should store a FileName object in e.g. InsetInclude
before caching will have any significant effect..
So, another patch, just with that change. Does this help?
Richard
I can't test right now, but I wouldn't expect major difference...
Vincent
