exchange: raise error.Abort instead of ValueError
Raising ValueError results in an uncaught exception and a traceback
being printed. In the context of servers, it can result in an HTTP
500 and an exception being logged in the error log.
I don't think this is proper behavior.
The bundle2 code paths have a mechanism for translating an
error.Abort into an error message reported to the clients. I
think we should use that instead.
This commit replaces some ValueError with Abort so that
servers can error more gracefully.
Differential Revision: https://phab.mercurial-scm.org/D5972
$ hg init r1
$ cd r1
$ hg ci --config ui.allowemptycommit=true -m c0
$ hg ci --config ui.allowemptycommit=true -m c1
$ hg ci --config ui.allowemptycommit=true -m c2
$ hg co -q 0
$ hg ci --config ui.allowemptycommit=true -m c3
created new head
$ hg co -q 3
$ hg merge --quiet
$ hg ci --config ui.allowemptycommit=true -m c4
$ hg log -G -T'{desc}'
@ c4
|\
| o c3
| |
o | c2
| |
o | c1
|/
o c0
>>> from mercurial import hg
>>> from mercurial import ui as uimod
>>> repo = hg.repository(uimod.ui())
>>> for anc in repo.changelog.ancestors([4], inclusive=True):
... print(anc)
4
3
2
1
0