--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/test-missing-capability.t Mon Dec 24 14:04:16 2018 -0500
@@ -0,0 +1,46 @@
+Checking how hg behaves when one side of a pull/push doesn't support
+some capability (because it's running an older hg version, usually).
+
+ $ hg init repo1
+ $ cd repo1
+ $ echo a > a; hg add -q a; hg commit -q -m a
+ $ hg bookmark a
+ $ hg clone -q . ../repo2
+ $ cd ../repo2
+
+ $ touch $TESTTMP/disable-lookup.py
+ $ disable_cap() {
+ > rm -f $TESTTMP/disable-lookup.pyc # pyc caching is buggy
+ > cat <<EOF > $TESTTMP/disable-lookup.py
+ > from mercurial import extensions, wireprotov1server
+ > def wcapabilities(orig, *args, **kwargs):
+ > cap = orig(*args, **kwargs)
+ > cap.remove('$1')
+ > return cap
+ > extensions.wrapfunction(wireprotov1server, '_capabilities', wcapabilities)
+ > EOF
+ > }
+ $ cat >> ../repo1/.hg/hgrc <<EOF
+ > [extensions]
+ > disable-lookup = $TESTTMP/disable-lookup.py
+ > EOF
+ $ cat >> .hg/hgrc <<EOF
+ > [ui]
+ > ssh = "$PYTHON" "$TESTDIR/dummyssh"
+ > EOF
+
+ $ hg pull ssh://user@dummy/repo1 -r tip -B a
+ pulling from ssh://user@dummy/repo1
+ no changes found
+
+ $ disable_cap lookup
+ $ hg pull ssh://user@dummy/repo1 -r tip -B a
+ pulling from ssh://user@dummy/repo1
+ abort: other repository doesn't support revision lookup, so a rev cannot be specified.
+ [255]
+
+ $ disable_cap pushkey
+ $ hg pull ssh://user@dummy/repo1 -r tip -B a
+ pulling from ssh://user@dummy/repo1
+ abort: remote bookmark a not found!
+ [255]