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

mkdir t
cd t
hg init
echo "[merge]" >> .hg/hgrc
echo "followcopies = 1" >> .hg/hgrc
echo foo > a
echo foo > a2
hg add a a2
hg ci -m "start" -d "0 0"
hg mv a b
hg mv a2 b2
hg ci -m "rename" -d "0 0"
echo "checkout"
hg co 0
echo blahblah > a
echo blahblah > a2
hg mv a2 c2
hg ci -m "modify" -d "0 0"
echo "merge"
hg merge -y --debug
hg status -AC
cat b
hg ci -m "merge" -d "0 0"
hg debugindex .hg/store/data/b.i
hg debugrename b