# HG changeset patch
# User Sushil khanchi <sushilkhanchi97@gmail.com>
# Date 1572811250 -19800
# Node ID 39d282fd04e0a4a4bc65c5c8c09ba25f235dd0c9
# Parent  a8ac174010a512aad9b6215798555da51d665ce5
evolve: add pre-check logic for content-divergence in rewriteutil.precheck()

For now, pre-check will abort if rewriting a rev create divergence (and
config experimental.evolution.allowdivergence is not set to True).
But this behaviour can be improved where instead of abort maybe we
can confirm the user to either proceed with divergence or some other
options depends on what command user is running.

Changes in test file are used to overrides the pre-check for testing
purpose (using experimental.evolution.allowdivergence=yes).

diff -r a8ac174010a5 -r 39d282fd04e0 hgext3rd/evolve/rewriteutil.py
--- a/hgext3rd/evolve/rewriteutil.py	Fri Dec 20 14:08:37 2019 +0700
+++ b/hgext3rd/evolve/rewriteutil.py	Mon Nov 04 01:30:50 2019 +0530
@@ -77,6 +77,15 @@
         msg %= (action, len(newunstable))
         hint = _(b"see 'hg help evolution.instability'")
         raise error.Abort(msg, hint=hint)
+    divrisk = revs_hascontentdivrisk(repo, revs)
+    allowdivergence = repo.ui.configbool(b'experimental',
+                                         b'evolution.allowdivergence')
+    if divrisk and not allowdivergence:
+        msg = _(b"revision being rewritten or one of its precursor was "
+                b"rewritten as %s, performing '%s' will create "
+                b"content-divergence") % (repo[divrisk[0]], action)
+        hint = _(b"For more, see 'hg help evolution.instability'")
+        raise error.Abort(msg, hint=hint)
 
 def bookmarksupdater(repo, oldid, tr):
     """Return a callable update(newid) updating the current bookmark
@@ -89,6 +98,14 @@
             repo._bookmarks.applychanges(repo, tr, bmchanges)
     return updatebookmarks
 
+def revs_hascontentdivrisk(repo, revs):
+    obsrevs = repo.revs(b'%ld and obsolete()', revs)
+    for r in obsrevs:
+        div = contentdivrisk(repo, repo[r])
+        if div:
+            return div
+    return []
+
 def disallowednewunstable(repo, revs):
     """Check that editing <revs> will not create disallowed unstable
 
@@ -257,10 +274,12 @@
         lockmod.release(tr, lock, wlock)
 
 def contentdivrisk(repo, ctx):
-    """logic to check if rewriting an obsolete cset will create divergence"""
+    """return divergent revision if rewriting an obsolete cset (ctx) will
+    create divergence"""
     # 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)
+    divergent = []
     sset = obsutil.successorssets(repo, ctx.node())
     nodivergencerisk = (len(sset) == 0
                         or (len(sset) == 1
@@ -271,6 +290,10 @@
         # case 2: one of the precursors of the rev being revived has a
         #     non-obsolete successor (we need divergentsets for this)
         from . import evolvecmd
-        if evolvecmd.divergentsets(repo, ctx):
-            nodivergencerisk = False
-    return not nodivergencerisk
+        divsets = evolvecmd.divergentsets(repo, ctx)
+        if divsets:
+            nsuccset = divsets[0][b'divergentnodes']
+            divergent.append(nsuccset[0][0])
+    else:
+        divergent.append(sset[0][0])
+    return divergent
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-amend.t
--- a/tests/test-amend.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-amend.t	Mon Nov 04 01:30:50 2019 +0530
@@ -121,6 +121,9 @@
   update: (current)
   phases: 3 draft
 
+setting the user after we have performed the test with no username
+  $ HGUSER=test
+
 Check the help
   $ hg amend -h
   hg amend [OPTION]... [FILE]...
@@ -170,3 +173,22 @@
   $ hg amend --patch --extract
   abort: cannot use both --patch and --extract
   [255]
+
+  $ cd ..
+
+Check the pre-check logic
+  $ hg init precheckrepo
+  $ cd precheckrepo
+  $ echo a > a
+  $ hg ci -Am "added a"
+  adding a
+  $ echo newchanges > a
+  $ hg amend
+  $ hg up 0 --hidden -q
+  updated to hidden changeset 9092f1db7931
+  (hidden revision '9092f1db7931' was rewritten as: aafaf407b00d)
+  working directory parent is obsolete! (9092f1db7931)
+  $ hg amend -m "i am gonna create divergence"
+  abort: revision being rewritten or one of its precursor was rewritten as aafaf407b00d, performing 'amend' will create content-divergence
+  (For more, see 'hg help evolution.instability')
+  [255]
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-evolve-content-divergent-basic.t
--- a/tests/test-evolve-content-divergent-basic.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-evolve-content-divergent-basic.t	Mon Nov 04 01:30:50 2019 +0530
@@ -21,6 +21,8 @@
   > unified = 0
   > [ui]
   > logtemplate = {rev}:{node|short}@{branch}({phase}) {desc|firstline} [{instabilities}]\n
+  > [experimental]
+  > evolution.allowdivergence = True
   > [extensions]
   > EOF
   $ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-evolve-content-divergent-corner-cases.t
--- a/tests/test-evolve-content-divergent-corner-cases.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-evolve-content-divergent-corner-cases.t	Mon Nov 04 01:30:50 2019 +0530
@@ -21,6 +21,8 @@
   > unified = 0
   > [ui]
   > logtemplate = {rev}:{node|short}@{branch}({phase}) {desc|firstline} [{instabilities}]\n
+  > [experimental]
+  > evolution.allowdivergence = True
   > [extensions]
   > EOF
   $ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-evolve-content-divergent-first-changeset.t
--- a/tests/test-evolve-content-divergent-first-changeset.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-evolve-content-divergent-first-changeset.t	Mon Nov 04 01:30:50 2019 +0530
@@ -1,6 +1,11 @@
   $ . $TESTDIR/testlib/pythonpath.sh
-  $ echo "[extensions]" >> $HGRCPATH
-  $ echo "evolve=" >> $HGRCPATH
+  $ cat >> $HGRCPATH << EOF
+  > [extensions]
+  > evolve=
+  > [experimental]
+  > evolution.allowdivergence = True
+  > EOF
+
 
 This test file tests the case of content-divergence resolution of changesets
 that have the null revision as the parent.
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-evolve-content-divergent-interrupted.t
--- a/tests/test-evolve-content-divergent-interrupted.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-evolve-content-divergent-interrupted.t	Mon Nov 04 01:30:50 2019 +0530
@@ -24,6 +24,8 @@
   > publish = False
   > [alias]
   > glog = log -GT "{rev}:{node|short} {desc}\n ({bookmarks}) {phase}"
+  > [experimental]
+  > evolution.allowdivergence = True
   > [extensions]
   > EOF
   $ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-evolve-content-divergent-meta.t
--- a/tests/test-evolve-content-divergent-meta.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-evolve-content-divergent-meta.t	Mon Nov 04 01:30:50 2019 +0530
@@ -12,6 +12,8 @@
   > glog = log -GT "{rev}:{node|short} {desc|firstline}\n {phase} {instabilities}\n\n"
   > [phases]
   > publish = False
+  > [experimental]
+  > evolution.allowdivergence = True
   > [extensions]
   > rebase =
   > strip =
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-evolve-obshistory-content-divergent.t
--- a/tests/test-evolve-obshistory-content-divergent.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-evolve-obshistory-content-divergent.t	Mon Nov 04 01:30:50 2019 +0530
@@ -5,6 +5,10 @@
 ============
 
   $ . $TESTDIR/testlib/obshistory_setup.sh
+  $ cat >> $HGRCPATH << EOF
+  > [experimental]
+  > evolution.allowdivergence = True
+  > EOF
 
 Test output with content-divergence
 ===================================
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-evolve-order.t
--- a/tests/test-evolve-order.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-evolve-order.t	Mon Nov 04 01:30:50 2019 +0530
@@ -15,6 +15,8 @@
   > unified = 0
   > [ui]
   > logtemplate = {rev}:{node|short}@{branch}({phase}) {desc|firstline}\n
+  > [experimental]
+  > evolution.allowdivergence = True
   > [extensions]
   > EOF
   $ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-evolve-public-content-divergent-corner-cases.t
--- a/tests/test-evolve-public-content-divergent-corner-cases.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-evolve-public-content-divergent-corner-cases.t	Mon Nov 04 01:30:50 2019 +0530
@@ -12,6 +12,8 @@
   > glog = log -GT "{rev}:{node|short} {desc|firstline}\n {phase} {instabilities}\n\n"
   > [phases]
   > publish = False
+  > [experimental]
+  > evolution.allowdivergence = True
   > [extensions]
   > rebase =
   > EOF
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-evolve-public-content-divergent-discard.t
--- a/tests/test-evolve-public-content-divergent-discard.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-evolve-public-content-divergent-discard.t	Mon Nov 04 01:30:50 2019 +0530
@@ -17,6 +17,8 @@
   > glog = log -GT "{rev}:{node|short} {desc|firstline}\n {phase} {instabilities}\n\n"
   > [phases]
   > publish = False
+  > [experimental]
+  > evolution.allowdivergence = True
   > [extensions]
   > rebase =
   > EOF
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-evolve-public-content-divergent-main.t
--- a/tests/test-evolve-public-content-divergent-main.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-evolve-public-content-divergent-main.t	Mon Nov 04 01:30:50 2019 +0530
@@ -15,6 +15,8 @@
   > glog = log -GT "{rev}:{node|short} {desc|firstline}\n {phase} {instabilities}\n\n"
   > [phases]
   > publish = False
+  > [experimental]
+  > evolution.allowdivergence = True
   > [extensions]
   > rebase =
   > EOF
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-evolve-templates.t
--- a/tests/test-evolve-templates.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-evolve-templates.t	Mon Nov 04 01:30:50 2019 +0530
@@ -9,6 +9,8 @@
   > interactive = true
   > [phases]
   > publish=False
+  > [experimental]
+  > evolution.allowdivergence = True
   > [extensions]
   > evolve =
   > [alias]
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-fold.t
--- a/tests/test-fold.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-fold.t	Mon Nov 04 01:30:50 2019 +0530
@@ -405,8 +405,8 @@
 
   $ hg fold --exact -r 'desc("A")::desc("B")' -m 'second fold' \
   >         --config experimental.evolution.allowdivergence=no
-  abort: folding obsolete revisions may cause divergence
-  (set experimental.evolution.allowdivergence=yes to allow folding them)
+  abort: revision being rewritten or one of its precursor was rewritten as fcfd42a7fa46, performing 'fold' will create content-divergence
+  (For more, see 'hg help evolution.instability')
   [255]
 
 but if we allow divergence, this should work and should create new content-divergent changesets
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-topic-stack-complex.t
--- a/tests/test-topic-stack-complex.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-topic-stack-complex.t	Mon Nov 04 01:30:50 2019 +0530
@@ -7,6 +7,7 @@
   $ cat << EOF >> $HGRCPATH
   > [experimental]
   > evolution = all
+  > evolution.allowdivergence = True
   > [ui]
   > interactive = True
   > [extensions]
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-touch.t
--- a/tests/test-touch.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-touch.t	Mon Nov 04 01:30:50 2019 +0530
@@ -6,6 +6,8 @@
   > amend=-d "0 0"
   > [alias]
   > glog = log -GT "{rev}: {desc}"
+  > [experimental]
+  > evolution.allowdivergence = True
   > [extensions]
   > hgext.rebase=
   > EOF
diff -r a8ac174010a5 -r 39d282fd04e0 tests/test-uncommit.t
--- a/tests/test-uncommit.t	Fri Dec 20 14:08:37 2019 +0700
+++ b/tests/test-uncommit.t	Mon Nov 04 01:30:50 2019 +0530
@@ -1,4 +1,6 @@
   $ cat >> $HGRCPATH <<EOF
+  > [experimental]
+  > evolution.allowdivergence = True
   > [extensions]
   > EOF
   $ echo "evolve=$(echo $(dirname $TESTDIR))/hgext3rd/evolve/" >> $HGRCPATH