Don't try to determine interactivity if ui() called with interactive=False. WSGI applications are not supposed to refer to sys.stdin. In ed6df6b1c29a, hgweb and hgwebdir were fixed to pass interactive=False to their ui()'s, but sys.stdin.isatty() was still called by the ui objects. This change makes sure only the ui.fixconfig() method will call ui.isatty() (by making the ui._readline() method, which is currently only called from ui.prompt(), private). ui.fixconfig() is changed to let config files override the initial interactivity setting, but not check isatty() if interactive=False was specified in the creation of the ui.

#!/bin/sh

hg init a
cd a
echo 'root' >root
hg add root
hg commit -d '0 0' -u test -m "Adding root node"

echo 'a' >a
hg add a
hg branch a
hg commit -d '1 0' -u test -m "Adding a branch"

hg update -C 0
echo 'b' >b
hg add b
hg branch b
hg commit -d '2 0' -u test -m "Adding b branch"

echo 'bh1' >bh1
hg add bh1
hg commit -d '3 0' -u test -m "Adding b branch head 1"

hg update -C 2
echo 'bh2' >bh2
hg add bh2
hg commit -d '4 0' -u test -m "Adding b branch head 2"

echo 'c' >c
hg add c
hg branch c
hg commit -d '5 0' -u test -m "Adding c branch"

hg branches
echo '-------'
hg branches -a