dirstate-tree: Add tree traversal/iteration
Like Python’s, Rust’s iterators are "external" in that they are driven
by a caller who calls a `next` method. This is as opposed to "internal"
iterators who drive themselves and call a callback for each item.
Writing an internal iterator traversing a tree is easy with recursion,
but internal iterators cannot rely on the call stack in that way,
they must save in an explicit object all state that they need to be
preserved across two `next` calls.
This algorithm uses a `Vec` as a stack that contains what would be
local variables on the call stack if we could use recursion.
Differential Revision: https://phab.mercurial-scm.org/D10370
#require no-msys # MSYS will translate web paths as if they were file paths
This tests if CGI files from after d0db3462d568 but
before d74fc8dec2b4 still work.
$ hg init test
$ cat >hgweb.cgi <<HGWEB
> #!$PYTHON
> #
> # An example CGI script to use hgweb, edit as necessary
>
> import cgitb
> cgitb.enable()
>
> from mercurial import demandimport; demandimport.enable()
> from mercurial.hgweb import hgweb
> from mercurial.hgweb import wsgicgi
> from mercurial.hgweb.request import wsgiapplication
>
> def make_web_app():
> return hgweb(b"test", b"Empty test repository")
>
> wsgicgi.launch(wsgiapplication(make_web_app))
> HGWEB
$ chmod 755 hgweb.cgi
$ cat >hgweb.config <<HGWEBDIRCONF
> [paths]
> test = test
> HGWEBDIRCONF
$ cat >hgwebdir.cgi <<HGWEBDIR
> #!$PYTHON
> #
> # An example CGI script to export multiple hgweb repos, edit as necessary
>
> import cgitb
> cgitb.enable()
>
> from mercurial import demandimport; demandimport.enable()
> from mercurial.hgweb import hgwebdir
> from mercurial.hgweb import wsgicgi
> from mercurial.hgweb.request import wsgiapplication
>
> def make_web_app():
> return hgwebdir(b"hgweb.config")
>
> wsgicgi.launch(wsgiapplication(make_web_app))
> HGWEBDIR
$ chmod 755 hgwebdir.cgi
$ . "$TESTDIR/cgienv"
$ "$PYTHON" hgweb.cgi > page1
$ "$PYTHON" hgwebdir.cgi > page2
$ PATH_INFO="/test/"
$ PATH_TRANSLATED="/var/something/test.cgi"
$ REQUEST_URI="/test/test/"
$ SCRIPT_URI="http://hg.omnifarious.org/test/test/"
$ SCRIPT_URL="/test/test/"
$ "$PYTHON" hgwebdir.cgi > page3
$ grep -i error page1 page2 page3
[1]