--- a/mercurial/commands.py	Tue Jun 26 02:05:11 2018 +0530
+++ b/mercurial/commands.py	Tue Jun 26 16:14:02 2018 +0530
@@ -2111,6 +2111,8 @@
      ('', 'abort', False, _('abort interrupted graft')),
      ('e', 'edit', False, _('invoke editor on commit messages')),
      ('', 'log', None, _('append graft info to log message')),
+     ('', 'no-commit', None,
+      _("don't commit, just apply the changes in working directory")),
      ('f', 'force', False, _('force graft')),
      ('D', 'currentdate', False,
       _('record the current date as commit date')),
@@ -2200,6 +2202,20 @@
                                      **pycompat.strkwargs(opts))
 
     cont = False
+    if opts.get('no_commit'):
+        if opts.get('edit'):
+            raise error.Abort(_("cannot specify --no-commit and "
+                                "--edit together"))
+        if opts.get('currentuser'):
+            raise error.Abort(_("cannot specify --no-commit and "
+                                "--currentuser together"))
+        if opts.get('currentdate'):
+            raise error.Abort(_("cannot specify --no-commit and "
+                                "--currentdate together"))
+        if opts.get('log'):
+            raise error.Abort(_("cannot specify --no-commit and "
+                                "--log together"))
+
     graftstate = statemod.cmdstate(repo, 'graftstate')
 
     if opts.get('stop'):
@@ -2237,6 +2253,8 @@
                 opts['user'] = statedata['user']
             if statedata.get('log'):
                 opts['log'] = True
+            if statedata.get('no_commit'):
+                opts['no_commit'] = statedata.get('no_commit')
             nodes = statedata['nodes']
             revs = [repo[node].rev() for node in nodes]
         else:
@@ -2323,6 +2341,8 @@
         if not revs:
             return -1
 
+    if opts.get('no_commit'):
+        statedata['no_commit'] = True
     for pos, ctx in enumerate(repo.set("%ld", revs)):
         desc = '%d:%s "%s"' % (ctx.rev(), ctx,
                                ctx.description().split('\n', 1)[0])
@@ -2373,16 +2393,17 @@
         else:
             cont = False
 
-        # commit
-        node = repo.commit(text=message, user=user,
-                    date=date, extra=extra, editor=editor)
-        if node is None:
-            ui.warn(
-                _('note: graft of %d:%s created no changes to commit\n') %
-                (ctx.rev(), ctx))
-        # checking that newnodes exist because old state files won't have it
-        elif statedata.get('newnodes') is not None:
-            statedata['newnodes'].append(node)
+        # commit if --no-commit is false
+        if not opts.get('no_commit'):
+            node = repo.commit(text=message, user=user, date=date, extra=extra,
+                               editor=editor)
+            if node is None:
+                ui.warn(
+                    _('note: graft of %d:%s created no changes to commit\n') %
+                    (ctx.rev(), ctx))
+            # checking that newnodes exist because old state files won't have it
+            elif statedata.get('newnodes') is not None:
+                statedata['newnodes'].append(node)
 
     # remove state when we complete successfully
     if not opts.get('dry_run'):

--- a/tests/test-completion.t	Tue Jun 26 02:05:11 2018 +0530
+++ b/tests/test-completion.t	Tue Jun 26 16:14:02 2018 +0530
@@ -312,7 +312,7 @@
   debugwireargs: three, four, five, ssh, remotecmd, insecure
   debugwireproto: localssh, peer, noreadstderr, nologhandshake, ssh, remotecmd, insecure
   files: rev, print0, include, exclude, template, subrepos
-  graft: rev, continue, stop, abort, edit, log, force, currentdate, currentuser, date, user, tool, dry-run
+  graft: rev, continue, stop, abort, edit, log, no-commit, force, currentdate, currentuser, date, user, tool, dry-run
   grep: print0, all, diff, text, follow, ignore-case, files-with-matches, line-number, rev, allfiles, user, date, template, include, exclude
   heads: rev, topo, active, closed, style, template
   help: extension, command, keyword, system

--- a/tests/test-graft.t	Tue Jun 26 02:05:11 2018 +0530
+++ b/tests/test-graft.t	Tue Jun 26 16:14:02 2018 +0530
@@ -1885,3 +1885,246 @@
   new changesets detected on destination branch, can't strip
   graft aborted
   working directory is now at 6b98ff0062dd
+
+  $ cd ..
+
+============================
+Testing --no-commit option:|
+============================
+
+  $ hg init nocommit
+  $ cd nocommit
+  $ echo a > a
+  $ hg ci -qAma
+  $ echo b > b
+  $ hg ci -qAmb
+  $ hg up -q 0
+  $ echo c > c
+  $ hg ci -qAmc
+  $ hg log -GT "{rev}:{node|short} {desc}\n"
+  @  2:d36c0562f908 c
+  |
+  | o  1:d2ae7f538514 b
+  |/
+  o  0:cb9a9f314b8b a
+  
+
+Check reporting when --no-commit used with non-applicable options:
+
+  $ hg graft 1 --no-commit -e
+  abort: cannot specify --no-commit and --edit together
+  [255]
+
+  $ hg graft 1 --no-commit --log
+  abort: cannot specify --no-commit and --log together
+  [255]
+
+  $ hg graft 1 --no-commit -D
+  abort: cannot specify --no-commit and --currentdate together
+  [255]
+
+Test --no-commit is working:
+  $ hg graft 1 --no-commit
+  grafting 1:d2ae7f538514 "b"
+
+  $ hg log -GT "{rev}:{node|short} {desc}\n"
+  @  2:d36c0562f908 c
+  |
+  | o  1:d2ae7f538514 b
+  |/
+  o  0:cb9a9f314b8b a
+  
+
+  $ hg diff
+  diff -r d36c0562f908 b
+  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+  +++ b/b	Thu Jan 01 00:00:00 1970 +0000
+  @@ -0,0 +1,1 @@
+  +b
+
+Prepare wrdir to check --no-commit is resepected after --continue:
+
+  $ hg up -qC
+  $ echo A>a
+  $ hg ci -qm "A in file a"
+  $ hg up -q 1
+  $ echo B>a
+  $ hg ci -qm "B in file a"
+  $ hg log -GT "{rev}:{node|short} {desc}\n"
+  @  4:2aa9ad1006ff B in file a
+  |
+  | o  3:09e253b87e17 A in file a
+  | |
+  | o  2:d36c0562f908 c
+  | |
+  o |  1:d2ae7f538514 b
+  |/
+  o  0:cb9a9f314b8b a
+  
+
+  $ hg graft 3 --no-commit
+  grafting 3:09e253b87e17 "A in file a"
+  merging a
+  warning: conflicts while merging a! (edit, then use 'hg resolve --mark')
+  abort: unresolved conflicts, can't continue
+  (use 'hg resolve' and 'hg graft --continue')
+  [255]
+
+Resolve conflict:
+  $ echo A>a
+  $ hg resolve --mark
+  (no more unresolved files)
+  continue: hg graft --continue
+
+  $ hg graft --continue
+  grafting 3:09e253b87e17 "A in file a"
+  $ hg log -GT "{rev}:{node|short} {desc}\n"
+  @  4:2aa9ad1006ff B in file a
+  |
+  | o  3:09e253b87e17 A in file a
+  | |
+  | o  2:d36c0562f908 c
+  | |
+  o |  1:d2ae7f538514 b
+  |/
+  o  0:cb9a9f314b8b a
+  
+  $ hg diff
+  diff -r 2aa9ad1006ff a
+  --- a/a	Thu Jan 01 00:00:00 1970 +0000
+  +++ b/a	Thu Jan 01 00:00:00 1970 +0000
+  @@ -1,1 +1,1 @@
+  -B
+  +A
+
+  $ hg up -qC
+
+Check --no-commit is resepected when passed with --continue:
+
+  $ hg graft 3
+  grafting 3:09e253b87e17 "A in file a"
+  merging a
+  warning: conflicts while merging a! (edit, then use 'hg resolve --mark')
+  abort: unresolved conflicts, can't continue
+  (use 'hg resolve' and 'hg graft --continue')
+  [255]
+
+Resolve conflict:
+  $ echo A>a
+  $ hg resolve --mark
+  (no more unresolved files)
+  continue: hg graft --continue
+
+  $ hg graft --continue --no-commit
+  grafting 3:09e253b87e17 "A in file a"
+  $ hg diff
+  diff -r 2aa9ad1006ff a
+  --- a/a	Thu Jan 01 00:00:00 1970 +0000
+  +++ b/a	Thu Jan 01 00:00:00 1970 +0000
+  @@ -1,1 +1,1 @@
+  -B
+  +A
+
+  $ hg log -GT "{rev}:{node|short} {desc}\n"
+  @  4:2aa9ad1006ff B in file a
+  |
+  | o  3:09e253b87e17 A in file a
+  | |
+  | o  2:d36c0562f908 c
+  | |
+  o |  1:d2ae7f538514 b
+  |/
+  o  0:cb9a9f314b8b a
+  
+  $ hg up -qC
+
+Test --no-commit when graft multiple revisions:
+When there is conflict:
+  $ hg graft -r "2::3" --no-commit
+  grafting 2:d36c0562f908 "c"
+  grafting 3:09e253b87e17 "A in file a"
+  merging a
+  warning: conflicts while merging a! (edit, then use 'hg resolve --mark')
+  abort: unresolved conflicts, can't continue
+  (use 'hg resolve' and 'hg graft --continue')
+  [255]
+
+  $ echo A>a
+  $ hg resolve --mark
+  (no more unresolved files)
+  continue: hg graft --continue
+  $ hg graft --continue
+  grafting 3:09e253b87e17 "A in file a"
+  $ hg diff
+  diff -r 2aa9ad1006ff a
+  --- a/a	Thu Jan 01 00:00:00 1970 +0000
+  +++ b/a	Thu Jan 01 00:00:00 1970 +0000
+  @@ -1,1 +1,1 @@
+  -B
+  +A
+  diff -r 2aa9ad1006ff c
+  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+  +++ b/c	Thu Jan 01 00:00:00 1970 +0000
+  @@ -0,0 +1,1 @@
+  +c
+
+  $ hg log -GT "{rev}:{node|short} {desc}\n"
+  @  4:2aa9ad1006ff B in file a
+  |
+  | o  3:09e253b87e17 A in file a
+  | |
+  | o  2:d36c0562f908 c
+  | |
+  o |  1:d2ae7f538514 b
+  |/
+  o  0:cb9a9f314b8b a
+  
+  $ hg up -qC
+
+When there is no conflict:
+  $ echo d>d
+  $ hg add d -q
+  $ hg ci -qmd
+  $ hg up 3 -q
+  $ hg log -GT "{rev}:{node|short} {desc}\n"
+  o  5:baefa8927fc0 d
+  |
+  o  4:2aa9ad1006ff B in file a
+  |
+  | @  3:09e253b87e17 A in file a
+  | |
+  | o  2:d36c0562f908 c
+  | |
+  o |  1:d2ae7f538514 b
+  |/
+  o  0:cb9a9f314b8b a
+  
+
+  $ hg graft -r 1 -r 5 --no-commit
+  grafting 1:d2ae7f538514 "b"
+  grafting 5:baefa8927fc0 "d" (tip)
+  $ hg diff
+  diff -r 09e253b87e17 b
+  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+  +++ b/b	Thu Jan 01 00:00:00 1970 +0000
+  @@ -0,0 +1,1 @@
+  +b
+  diff -r 09e253b87e17 d
+  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+  +++ b/d	Thu Jan 01 00:00:00 1970 +0000
+  @@ -0,0 +1,1 @@
+  +d
+  $ hg log -GT "{rev}:{node|short} {desc}\n"
+  o  5:baefa8927fc0 d
+  |
+  o  4:2aa9ad1006ff B in file a
+  |
+  | @  3:09e253b87e17 A in file a
+  | |
+  | o  2:d36c0562f908 c
+  | |
+  o |  1:d2ae7f538514 b
+  |/
+  o  0:cb9a9f314b8b a
+  
+  $ cd ..