--- a/mercurial/rewriteutil.py Wed Apr 28 08:48:10 2021 -0700
+++ b/mercurial/rewriteutil.py Tue Feb 23 10:28:42 2021 -0800
@@ -44,7 +44,9 @@
revs = (r.rev() for r in revs)
if len(repo[None].parents()) > 1:
- raise error.StateError(_(b"cannot %s changesets while merging") % action)
+ raise error.StateError(
+ _(b"cannot %s changesets while merging") % action
+ )
publicrevs = repo.revs(b'%ld and public()', revs)
if publicrevs:
@@ -59,6 +61,38 @@
_(b"cannot %s changeset with children") % action, hint=hint
)
+ if not obsolete.isenabled(repo, obsolete.allowdivergenceopt):
+ new_divergence = _find_new_divergence(repo, revs)
+ if new_divergence:
+ local_ctx, other_ctx, base_ctx = new_divergence
+ msg = _(
+ b'cannot %s %s, as that creates content-divergence with %s'
+ ) % (
+ action,
+ local_ctx,
+ other_ctx,
+ )
+ if local_ctx.rev() != base_ctx.rev():
+ msg += _(b', from %s') % base_ctx
+ if repo.ui.verbose:
+ if local_ctx.rev() != base_ctx.rev():
+ msg += _(
+ b'\n changeset %s is a successor of ' b'changeset %s'
+ ) % (local_ctx, base_ctx)
+ msg += _(
+ b'\n changeset %s already has a successor in '
+ b'changeset %s\n'
+ b' rewriting changeset %s would create '
+ b'"content-divergence"\n'
+ b' set experimental.evolution.allowdivergence=True to '
+ b'skip this check'
+ ) % (base_ctx, other_ctx, local_ctx)
+ raise error.InputError(msg)
+ else:
+ raise error.InputError(
+ msg, hint=_(b"add --verbose for details")
+ )
+
def disallowednewunstable(repo, revs):
"""Checks whether editing the revs will create new unstable changesets and
@@ -73,6 +107,40 @@
return repo.revs(b"(%ld::) - %ld", revs, revs)
+def _find_new_divergence(repo, revs):
+ obsrevs = repo.revs(b'%ld and obsolete()', revs)
+ for r in obsrevs:
+ div = find_new_divergence_from(repo, repo[r])
+ if div:
+ return (repo[r], repo[div[0]], repo[div[1]])
+ return None
+
+
+def find_new_divergence_from(repo, ctx):
+ """return divergent revision if rewriting an obsolete cset (ctx) will
+ create divergence
+
+ Returns (<other node>, <common ancestor node>) or None
+ """
+ if not ctx.obsolete():
+ return None
+ # We need to check two cases that can cause divergence:
+ # case 1: the rev being rewritten has a non-obsolete successor (easily
+ # detected by successorssets)
+ sset = obsutil.successorssets(repo, ctx.node())
+ if sset:
+ return (sset[0][0], ctx.node())
+ else:
+ # case 2: one of the precursors of the rev being revived has a
+ # non-obsolete successor (we need divergentsets for this)
+ divsets = obsutil.divergentsets(repo, ctx)
+ if divsets:
+ nsuccset = divsets[0][b'divergentnodes']
+ prec = divsets[0][b'commonpredecessor']
+ return (nsuccset[0], prec)
+ return None
+
+
def skip_empty_successor(ui, command):
empty_successor = ui.config(b'rewrite', b'empty-successor')
if empty_successor == b'skip':