# HG changeset patch
# User Dan Villiom Podlaski Christiansen <danchr@gmail.com>
# Date 1603976065 -3600
# Node ID 976b26bdd0d82e0b91be5543ffbad9c813b91091
# Parent  4404f129341ea0c847668c04ca9384fe390c4405
commit: warn the user when a commit already exists

Sometimes, a commit will result in an exact match of a preexisting
commit, and if that commit isn't a branch head, hg will incorrectly
note that it created a new head. Instead, we should warn the user that
commit already existed in the repository.

In practice, this bug is rather uncommon, and will only occur when the
usr explicitly sets the date.

Please note that this commit contains an API change to
cmdutil.commitstatus()

Differential Revision: https://phab.mercurial-scm.org/D9257

diff -r 4404f129341e -r 976b26bdd0d8 mercurial/cmdutil.py
--- a/mercurial/cmdutil.py	Tue Oct 06 13:34:51 2020 +0200
+++ b/mercurial/cmdutil.py	Thu Oct 29 13:54:25 2020 +0100
@@ -3113,13 +3113,18 @@
     return b"\n".join(edittext)
 
 
-def commitstatus(repo, node, branch, bheads=None, opts=None):
+def commitstatus(repo, node, branch, bheads=None, tip=None, opts=None):
     if opts is None:
         opts = {}
     ctx = repo[node]
     parents = ctx.parents()
 
-    if (
+    if tip is not None and repo.changelog.tip() == tip:
+        # avoid reporting something like "committed new head" when
+        # recommitting old changesets, and issue a helpful warning
+        # for most instances
+        repo.ui.warn(_("warning: commit already existed in the repository!\n"))
+    elif (
         not opts.get(b'amend')
         and bheads
         and node not in bheads
diff -r 4404f129341e -r 976b26bdd0d8 mercurial/commands.py
--- a/mercurial/commands.py	Tue Oct 06 13:34:51 2020 +0200
+++ b/mercurial/commands.py	Thu Oct 29 13:54:25 2020 +0100
@@ -851,11 +851,14 @@
             message, opts.get(b'user'), opts.get(b'date'), match, editor=e
         )
 
+    # save to detect changes
+    tip = repo.changelog.tip()
+
     newnode = cmdutil.commit(ui, repo, commitfunc, [], opts)
     if not newnode:
         ui.status(_(b"nothing changed\n"))
         return 1
-    cmdutil.commitstatus(repo, newnode, branch, bheads)
+    cmdutil.commitstatus(repo, newnode, branch, bheads, tip)
 
     def nice(node):
         return b'%d:%s' % (repo.changelog.rev(node), short(node))
@@ -2024,6 +2027,7 @@
 
     branch = repo[None].branch()
     bheads = repo.branchheads(branch)
+    tip = repo.changelog.tip()
 
     extra = {}
     if opts.get(b'close_branch') or opts.get(b'force_close_branch'):
@@ -2113,7 +2117,7 @@
                 ui.status(_(b"nothing changed\n"))
             return 1
 
-    cmdutil.commitstatus(repo, node, branch, bheads, opts)
+    cmdutil.commitstatus(repo, node, branch, bheads, tip, opts)
 
     if not ui.quiet and ui.configbool(b'commands', b'commit.post-status'):
         status(
diff -r 4404f129341e -r 976b26bdd0d8 tests/test-backout.t
--- a/tests/test-backout.t	Tue Oct 06 13:34:51 2020 +0200
+++ b/tests/test-backout.t	Thu Oct 29 13:54:25 2020 +0100
@@ -819,5 +819,5 @@
   1 files updated, 0 files merged, 1 files removed, 0 files unresolved
   $ hg backout 2
   removing 3
-  created new head
+  warning: commit already existed in the repository!
   changeset 3:8f188de730d9 backs out changeset 2:cccc23d9d68f
diff -r 4404f129341e -r 976b26bdd0d8 tests/test-merge-tools.t
--- a/tests/test-merge-tools.t	Tue Oct 06 13:34:51 2020 +0200
+++ b/tests/test-merge-tools.t	Thu Oct 29 13:54:25 2020 +0100
@@ -1868,6 +1868,7 @@
   $ hg update -q -C 1
   $ hg mv f f.txt
   $ hg ci -qm "f.txt"
+  warning: commit already existed in the repository!
   $ hg update -q -C 2
   $ hg merge -y -r tip --tool echo \
   >    --config merge-tools.echo.args='$base $local $other $output' \
diff -r 4404f129341e -r 976b26bdd0d8 tests/test-phases.t
--- a/tests/test-phases.t	Tue Oct 06 13:34:51 2020 +0200
+++ b/tests/test-phases.t	Thu Oct 29 13:54:25 2020 +0100
@@ -1010,7 +1010,7 @@
   $ hg up -C 1
   0 files updated, 0 files merged, 4 files removed, 0 files unresolved
   $ mkcommit C
-  created new head
+  warning: commit already existed in the repository!
   $ hg phase -r 2
   2: public
 
@@ -1027,6 +1027,7 @@
   7: draft
   $ mkcommit F
   test-debug-phase: new rev 8:  x -> 2
+  warning: commit already existed in the repository!
   test-hook-close-phase: de414268ec5ce2330c590b942fbb5ff0b0ca1a0a:   -> secret
   $ hg phase -r tip
   8: secret
@@ -1037,7 +1038,7 @@
   0 files updated, 0 files merged, 2 files removed, 0 files unresolved
   $ mkcommit H
   test-debug-phase: new rev 5:  x -> 2
-  created new head
+  warning: commit already existed in the repository!
   test-hook-close-phase: a030c6be5127abc010fcbff1851536552e6951a8:   -> secret
   $ hg phase -r 5
   5: secret
diff -r 4404f129341e -r 976b26bdd0d8 tests/test-remotefilelog-local.t
--- a/tests/test-remotefilelog-local.t	Tue Oct 06 13:34:51 2020 +0200
+++ b/tests/test-remotefilelog-local.t	Thu Oct 29 13:54:25 2020 +0100
@@ -204,5 +204,6 @@
   $ hg update -r '.^' -q
   $ echo 1 > A
   $ hg commit -m foo -A A
+  warning: commit already existed in the repository!
   $ hg log -r . -T '{node}\n'
   383ce605500277f879b7460a16ba620eb6930b7f
diff -r 4404f129341e -r 976b26bdd0d8 tests/test-unamend.t
--- a/tests/test-unamend.t	Tue Oct 06 13:34:51 2020 +0200
+++ b/tests/test-unamend.t	Thu Oct 29 13:54:25 2020 +0100
@@ -405,8 +405,10 @@
   $ hg co -q 0
   $ hg mv a b
   $ hg ci -qm 'move to a b'
+  warning: commit already existed in the repository!
   $ hg mv b c
   $ hg amend
+  warning: commit already existed in the repository!
   $ hg mv c d
   $ hg unamend
   $ hg st --copies --change .