[issue23407] os.walk always follows Windows junctions

[Eryk Sun]

Eryk Sun added the comment:

I opened issue 29248 for the os.readlink bug and issue 29250 for the inconsistency between os.path.islink and os.stat.

Handling junctions as links is new behavior, so I've changed this issue to be an enhancement for 3.7.

If the notion of a link is generalized to junctions, then maybe it should be further generalized to include all name-surrogate reparse tags [1]. Currently for Microsoft tags this includes 

    IO_REPARSE_TAG_MOUNT_POINT (junctions)
    IO_REPARSE_TAG_SYMLINK
    IO_REPARSE_TAG_IIS_CACHE

For non-Microsoft tags it includes 

    IO_REPARSE_TAG_SOLUTIONSOFT
    IO_REPARSE_TAG_OSR_SAMPLE
    IO_REPARSE_TAG_QI_TECH_HSM
    IO_REPARSE_TAG_MAXISCALE_HSM

The last two are outliers. HSM isn't the kind of immediate, fast access that one would expect from a symbolic link. All other HSM tags aren't categorized as name surrogates.

[1]: https://msdn.microsoft.com/en-us/library/aa365511

----------
type: behavior -> enhancement
versions: +Python 3.7 -Python 3.4, Python 3.5

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue23407>
_______________________________________