strip mutation extras when pushrebasing commits

Summary:
In the future we will be introducing mutation recording in commit extras.  For
pushrebase, these fields need to be stripped when the commit is rebased.  This
matches the Mercurial server behaviour.

At some point we will update Mononoke pushrebase to fill in these fields with
the pushrebase information, but that can wait until it is more widely deployed.

Reviewed By: quark-zju

Differential Revision: D14263856

fbshipit-source-id: 78b682fc580695137fd1fd4a4f65210a77f16b24

bundle2-resolver/pushrebase/src/lib.rs

@@ -737,6 +737,11 @@ fn rebase_changeset(
         None => (),
     }
 
+    // Mutation information from the original commit must be stripped.
+    for key in &["mutpred", "mutuser", "mutdate", "mutop", "mutsplit"] {
+        bcs.extra.remove(*key);
+    }
+
     // Copy information in bonsai changeset contains a commit parent. So parent changes, then
     // copy information for all copied/moved files needs to be updated
     bcs.file_changes = bcs

tests/integration/test-pushrebase-mutation.t

@@ -0,0 +1,92 @@
+  $ . $TESTDIR/library.sh
+
+setup configuration
+  $ setup_common_config "blob:files"
+  $ cd $TESTTMP
+
+setup common configuration
+  $ setconfig ui.ssh="\"$DUMMYSSH\"" mutation.date="0 0"
+  $ enable amend
+
+  $ newrepo repo-hg
+  $ setup_hg_server
+  $ echo base > base
+  $ hg commit -Aqm base
+  $ hg bookmark master -r tip
+
+blobimport
+  $ cd $TESTTMP
+  $ blobimport repo-hg/.hg repo
+
+start mononoke
+  $ mononoke
+  $ wait_for_mononoke $TESTTMP/repo
+
+clone the repo
+  $ hgclone_treemanifest ssh://user@dummy/repo-hg client --noupdate --config extensions.remotenames= -q
+  $ cd client
+  $ setup_hg_client
+  $ enable pushrebase remotenames
+
+create a commit with mutation extras
+  $ hg up -q 0
+  $ echo 1 > 1 && hg add 1 && hg commit -m 1
+  $ echo 1a > 1 && hg amend -m 1a --config mutation.record=true
+  $ hg debugmutation .
+    62fddca11dc5682b0377a89881b0fff7c042b7c4 amend by test at 1970-01-01T00:00:00 from:
+      f0161ad23099c690115006c21e96f780f5d740b6
+
+pushrebase it directly onto master - it will be rewritten without the mutation extras
+  $ hgmn push -r . --to master
+  remote: * Session with Mononoke started with uuid: * (glob)
+  pushing rev 62fddca11dc5 to destination ssh://user@dummy/repo bookmark master
+  searching for changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 1 changesets with 0 changes to 0 files (+1 heads)
+  updating bookmark master
+
+  $ tglog
+  o  3: a05b3505b7d1 '1a'
+  |
+  | @  2: 62fddca11dc5 '1a'
+  |/
+  o  0: d20a80d4def3 'base'
+  
+  $ hg debugmutation master
+    a05b3505b7d1aac5fd90b09a5f014822647ec205
+
+create another commit on the base commit with mutation extras
+  $ hg up 0
+  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  $ echo 2 > 2 && hg add 2 && hg commit -m 2
+  $ echo 2a > 2 && hg amend -m 2a --config mutation.record=true
+  $ hg debugmutation .
+    a805bbad06476c09727930617acfe8d6623f8d88 amend by test at 1970-01-01T00:00:00 from:
+      1b9fe529321657f93e84f23afaf9c855b9af34ff
+
+pushrebase it onto master - it will be rebased and rewritten without the mutation extras
+  $ hgmn push -r . --to master
+  remote: * Session with Mononoke started with uuid: * (glob)
+  pushing rev a805bbad0647 to destination ssh://user@dummy/repo bookmark master
+  searching for changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 1 changesets with 0 changes to 0 files
+  updating bookmark master
+
+  $ tglog
+  o  6: 7042a534cddc '2a'
+  |
+  | @  5: a805bbad0647 '2a'
+  | |
+  o |  3: a05b3505b7d1 '1a'
+  |/
+  | o  2: 62fddca11dc5 '1a'
+  |/
+  o  0: d20a80d4def3 'base'
+  
+  $ hg debugmutation master
+    7042a534cddcd761aeea38446ce39590634568e8