#
#
# add_file "tests/resolve_conflicts_all_resolutions/merge3_hook.lua"
#  content [742df075bd83fcd250b6c7476b0a7bad4151f81e]
# 
# add_file "tests/resolve_conflicts_all_resolutions/show_first-interactive"
#  content [7abca3d3c5a80fd96a1991a86d0e1b5395851feb]
# 
# patch "cmd_conflicts.cc"
#  from [4cadb787981f0b6bf5bba88ca7d31f2866bcaf5d]
#    to [419fe5e356704374a400c7e679eac0a1d2658ce9]
# 
# patch "monotone.texi"
#  from [ecedcde4c73e4cfb2db1d8ec74077ef5abe65a54]
#    to [d4d8166717d7a91bcca0f54ffb7225d35a2caaa4]
# 
# patch "options_list.hh"
#  from [3bb5b9b1bd536dfe468700f54e22603ddc0abb92]
#    to [0027aea743f03cfcaaa48cdd7c979c9782c72d6f]
# 
# patch "roster_merge.cc"
#  from [76d7a8b6130772c5b0da6ca8db48856d6cae0463]
#    to [d5c979ae93fd972fbca04fab78da8d99cf08e402]
# 
# patch "roster_merge.hh"
#  from [122f23807d016675871888e41ef496f4fdc352a9]
#    to [70962158e3ca990c80c46074a88cf84edd70a14c]
# 
# patch "tests/resolve_conflicts_all_resolutions/__driver__.lua"
#  from [51025b5e3e0cfd195b905975cae905939a95ce94]
#    to [050392dc818517aa201a0930f59a1969c96c4495]
# 
# patch "tests/resolve_conflicts_all_resolutions/conflicts-1"
#  from [bf24db060f7d4f25c09eff14083d02b9e6a2533b]
#    to [09ae554632fc05d64f3f59b9e536380d937895eb]
# 
# patch "tests/resolve_conflicts_all_resolutions/conflicts-resolved"
#  from [4018b395bff3124e1d091e5c600462c88cf8ea62]
#    to [bbfb68dde1ac7c4394118c6efa86ef722167183b]
# 
# patch "tests/resolve_conflicts_all_resolutions/merge-1"
#  from [4d660533ce23cbfacdc84e5fed181452a20f8b36]
#    to [8e3a1ba80b20c6b945ab48e83d5ce0df06720c1a]
# 
# patch "tests/resolve_conflicts_all_resolutions/show_first-user"
#  from [abab342008177d9c3dd49edfb582f0b9f483003e]
#    to [28e16e7e03af8954cbbd55b17827c92bc51f4bbf]
# 
# patch "tests/resolve_conflicts_all_resolutions/show_remaining-checkout_left"
#  from [cd1882e61df967d6ee9f21f466be8d0a03c88fb5]
#    to [457e3d43e1c99cff6224665099b74068733ed97a]
# 
# patch "tests/resolve_conflicts_all_resolutions/show_remaining-thermostat"
#  from [2bf5ad8ca1cd6a549e4bbe01c0e0440b99dabb61]
#    to [7ec8e586d80ebca3687341f78f60b0aacb329678]
#
============================================================
--- tests/resolve_conflicts_all_resolutions/merge3_hook.lua	742df075bd83fcd250b6c7476b0a7bad4151f81e
+++ tests/resolve_conflicts_all_resolutions/merge3_hook.lua	742df075bd83fcd250b6c7476b0a7bad4151f81e
@@ -0,0 +1,8 @@
+-- show that we called the merge3 hook
+
+function merge3 (anc_path, left_path, right_path, merged_path, ancestor, left, right)
+   io.write("running merge3 hook\n")
+   return "interactive_file merged"
+end
+
+-- end of file
============================================================
--- tests/resolve_conflicts_all_resolutions/show_first-interactive	7abca3d3c5a80fd96a1991a86d0e1b5395851feb
+++ tests/resolve_conflicts_all_resolutions/show_first-interactive	7abca3d3c5a80fd96a1991a86d0e1b5395851feb
@@ -0,0 +1,4 @@
+mtn: content interactive_file
+mtn: possible resolutions:
+mtn: resolve_first interactive "file_name"
+mtn: resolve_first user "file_name"
============================================================
--- cmd_conflicts.cc	4cadb787981f0b6bf5bba88ca7d31f2866bcaf5d
+++ cmd_conflicts.cc	419fe5e356704374a400c7e679eac0a1d2658ce9
@@ -23,6 +23,7 @@ struct conflicts_t
 {
   roster_merge_result result;
   revision_id ancestor_rid, left_rid, right_rid;
+  boost::shared_ptr<roster_t> ancestor_roster;
   boost::shared_ptr<roster_t> left_roster;
   boost::shared_ptr<roster_t> right_roster;
   marking_map left_marking, right_marking;
@@ -108,7 +109,8 @@ show_conflicts(database & db, conflicts_
             {
             case first:
               P(F("possible resolutions:"));
-              P(F("resolve user \"file_name\""));
+              P(F("resolve_first interactive \"file_name\""));
+              P(F("resolve_first user \"file_name\""));
               return;
 
             case remaining:
@@ -165,6 +167,47 @@ static char const * const conflict_resol
 enum side_t {left, right, neither};
 static char const * const conflict_resolution_not_supported_msg = "%s is not a supported conflict resolution for %s";
 
+// Call Lua merge3 hook to merge left_fid, right_fid, store result in result_path
+static bool
+do_interactive_merge(database & db,
+                     lua_hooks & lua,
+                     conflicts_t & conflicts,
+                     node_id const nid,
+                     file_id const & ancestor_fid,
+                     file_id const & left_fid,
+                     file_id const & right_fid,
+                     bookkeeping_path const & result_path)
+{
+  file_path ancestor_path, left_path, right_path;
+
+  if (!conflicts.ancestor_roster)
+    {
+      conflicts.ancestor_roster = boost::shared_ptr<roster_t>(new roster_t());
+      db.get_roster(conflicts.ancestor_rid, *conflicts.ancestor_roster);
+    }
+
+  conflicts.ancestor_roster->get_name(nid, ancestor_path);
+  conflicts.left_roster->get_name(nid, left_path);
+  conflicts.right_roster->get_name(nid, right_path);
+  
+  file_data left_data, right_data, ancestor_data;
+  data merged_unpacked;
+
+  db.get_file_version(left_fid, left_data);
+  db.get_file_version(ancestor_fid, ancestor_data);
+  db.get_file_version(right_fid, right_data);
+
+  if (lua.hook_merge3(ancestor_path, left_path, right_path, file_path(),
+                      ancestor_data.inner(), left_data.inner(),
+                      right_data.inner(), merged_unpacked))
+    {
+      write_data(result_path, merged_unpacked);
+      return true;
+    }
+
+  return false;
+} // do_interactive_merge
+
 static void
 set_duplicate_name_conflict(resolve_conflicts::file_resolution_t & resolution,
                             args_vector const & args)
@@ -192,7 +235,11 @@ static void
 } //set_duplicate_name_conflict
 
 static void
-set_first_conflict(side_t side, conflicts_t & conflicts, args_vector const & args)
+set_first_conflict(database & db,
+                   lua_hooks & lua,
+                   conflicts_t & conflicts,
+                   args_vector const & args,
+                   side_t side)
 {
   if (side != neither)
     {
@@ -236,10 +283,25 @@ set_first_conflict(side_t side, conflict
 
           if (conflict.resolution.first == resolve_conflicts::none)
             {
-              if ("user" == idx(args,0)())
+              if ("interactive" == idx(args,0)())
                 {
+                  N(bookkeeping_path::external_string_is_bookkeeping_path(utf8(idx(args,1)())),
+                    F("result path must be under _MTN"));
+                  bookkeeping_path const result_path(idx(args,1)());
+                  
                   N(args.size() == 2, F("wrong number of arguments"));
 
+                  if (do_interactive_merge(db, lua, conflicts, conflict.nid,
+                                           conflict.ancestor, conflict.left, conflict.right, result_path))
+                    {
+                      conflict.resolution.first  = resolve_conflicts::content_user;
+                      conflict.resolution.second = boost::shared_ptr<any_path>(new bookkeeping_path(result_path));
+                    }
+                }
+              else if ("user" == idx(args,0)())
+                {
+                  N(args.size() == 2, F("wrong number of arguments"));
+
                   conflict.resolution.first  = resolve_conflicts::content_user;
                   conflict.resolution.second = new_optimal_path(idx(args,1)(), false);
                 }
@@ -310,7 +372,7 @@ CMD(resolve_first, "resolve_first", "", 
   database db(app);
   conflicts_t conflicts (db, app.opts.conflicts_file);
 
-  set_first_conflict(neither, conflicts, args);
+  set_first_conflict(db, app.lua, conflicts, args, neither);
 
   conflicts.write (db, app.lua, app.opts.conflicts_file);
 }
@@ -324,7 +386,7 @@ CMD(resolve_first_left, "resolve_first_l
   database db(app);
   conflicts_t conflicts (db, app.opts.conflicts_file);
 
-  set_first_conflict(left, conflicts, args);
+  set_first_conflict(db, app.lua, conflicts, args, left);
 
   conflicts.write (db, app.lua, app.opts.conflicts_file);
 }
@@ -338,7 +400,7 @@ CMD(resolve_first_right, "resolve_first_
   database db(app);
   conflicts_t conflicts (db, app.opts.conflicts_file);
 
-  set_first_conflict(right, conflicts, args);
+  set_first_conflict(db, app.lua, conflicts, args, right);
 
   conflicts.write (db, app.lua, app.opts.conflicts_file);
 }
============================================================
--- monotone.texi	ecedcde4c73e4cfb2db1d8ec74077ef5abe65a54
+++ monotone.texi	d4d8166717d7a91bcca0f54ffb7225d35a2caaa4
@@ -4714,9 +4714,18 @@ @subsection Conflicts
 convenient way to clean up.
 @end ftable
 
-For single file conflicts, the only possible resolution is:
+For single file conflicts, there are two possible resolutions:
 
 @ftable @command
address@hidden interactive @var{file}
+The Lua @code{merge3} hook is called to allow the user to manually
+merge the left and right files, leaving the result in the specified file.
+
address@hidden must be a bookkeeping path; under @file{_MTN}.
+
+This inserts a @var{resolved_user file} conflict resolution in the
+conflicts file.
+
 @item user @var{file}
 The file contents are replaced by the contents of the specified file.
 
============================================================
--- options_list.hh	3bb5b9b1bd536dfe468700f54e22603ddc0abb92
+++ options_list.hh	0027aea743f03cfcaaa48cdd7c979c9782c72d6f
@@ -644,7 +644,9 @@ OPTION(resolve_conflicts_opts, resolve_c
        gettext_noop("use file to resolve conflicts"))
 #ifdef option_bodies
 {
-  N(bookkeeping_path::external_string_is_bookkeeping_path(utf8(arg)),
+  // we can't call  bookkeeping_path::external_string_is_bookkeeping_path
+  // here, because we haven't found the workspace yet.
+  N(bookkeeping_path::internal_string_is_bookkeeping_path(utf8(arg)),
     F("conflicts file must be under _MTN"));
   resolve_conflicts_file = bookkeeping_path(arg);
 }
@@ -667,7 +669,9 @@ OPTION(conflicts_opts, conflicts_file, t
        gettext_noop("file in which to store conflicts"))
 #ifdef option_bodies
 {
-  N(bookkeeping_path::external_string_is_bookkeeping_path(utf8(arg)),
+  // we can't call bookkeeping_path::external_string_is_bookkeeping_path
+  // here, because we haven't found the workspace yet.
+  N(bookkeeping_path::internal_string_is_bookkeeping_path(utf8(arg)),
     F("conflicts file must be under _MTN"));
   conflicts_file = bookkeeping_path(arg);
 }
============================================================
--- roster_merge.cc	76d7a8b6130772c5b0da6ca8db48856d6cae0463
+++ roster_merge.cc	d5c979ae93fd972fbca04fab78da8d99cf08e402
@@ -2105,13 +2105,16 @@ read_file_content_conflict(basic_io::par
   pars.esym(syms::node_type); pars.str(tmp); I(tmp == "file");
 
   pars.esym (syms::ancestor_name); pars.str();
-  pars.esym (syms::ancestor_file_id); pars.hex();
-
+  pars.esym (syms::ancestor_file_id); pars.hex(tmp);
+  conflict.ancestor = file_id(decode_hexenc(tmp));
+  
   pars.esym (syms::left_name); pars.str(left_name);
-  pars.esym(syms::left_file_id); pars.hex();
+  pars.esym(syms::left_file_id); pars.hex(tmp);
+  conflict.left = file_id(decode_hexenc(tmp));
 
   pars.esym (syms::right_name); pars.str(right_name);
-  pars.esym(syms::right_file_id); pars.hex();
+  pars.esym(syms::right_file_id); pars.hex(tmp);
+  conflict.right = file_id(decode_hexenc(tmp));
 
   conflict.nid = left_roster.get_node (file_path_internal (left_name))->self;
   I(conflict.nid = right_roster.get_node (file_path_internal (right_name))->self);
@@ -2269,6 +2272,8 @@ roster_merge_result::read_conflict_file(
   pars.hex(temp);
   ancestor_rid = revision_id(decode_hexenc(temp));
 
+  // we don't fetch the ancestor roster here, because not every function
+  // needs it.
   db.get_roster(left_rid, left_roster, left_marking);
   db.get_roster(right_rid, right_roster, right_marking);
 
============================================================
--- roster_merge.hh	122f23807d016675871888e41ef496f4fdc352a9
+++ roster_merge.hh	70962158e3ca990c80c46074a88cf84edd70a14c
@@ -133,7 +133,7 @@ struct file_content_conflict
 struct file_content_conflict
 {
   node_id nid;
-  file_id left, right;
+  file_id ancestor, left, right; // ancestor is set only when reading in a conflicts file
   resolve_conflicts::file_resolution_t resolution;
 
   file_content_conflict () :
============================================================
--- tests/resolve_conflicts_all_resolutions/__driver__.lua	51025b5e3e0cfd195b905975cae905939a95ce94
+++ tests/resolve_conflicts_all_resolutions/__driver__.lua	050392dc818517aa201a0930f59a1969c96c4495
@@ -2,6 +2,7 @@ mtn_setup()
 -- conflict file. Also test 'conflict show_remaining'.
 
 mtn_setup()
+get("merge3_hook.lua")
 
 -- Generate a conflicts file, with one conflict for each type of
 -- resolution. The list of currently supported resolutions is in
@@ -15,18 +16,25 @@ mtn_setup()
 -- resolved_rename_left     thermostat.c -> thermostat-westinghouse.c
 -- resolved_rename_right    thermostat.c -> thermostat-honeywell.c
 -- resolved_user            user_file
+-- resolved_user            interactive_file
 -- resolved_user_left       checkout_left.sh beth
 -- resolved_user_right      checkout_right.sh abe
 --
 -- We can't set 'resolved_internal' directly; it is set by 'conflicts store'.
+--
+-- We have two files that have 'resolved_user' resolutions; one by 'mtn
+-- conflicts resolve_first user ...', one by 'mtn conflicts
+-- resolve_first interactive ...'.
 
 addfile("simple_file", "simple\none\ntwo\nthree\n")
 addfile("user_file", "blah blah blah")
+addfile("interactive_file", "interactive base")
 commit()
 base = base_revision()
 
 addfile("simple_file", "simple\nzero\none\ntwo\nthree\n")
 writefile("user_file", "user_file abe 1")
+writefile("interactive_file", "interactive_file abe 1")
 addfile("checkout_left.sh", "checkout_left.sh abe 1")
 addfile("checkout_right.sh", "checkout_right.sh abe 1")
 addfile("thermostat.c", "thermostat westinghouse")
@@ -37,6 +45,7 @@ writefile("user_file", "user_file beth 1
 
 addfile("simple_file", "simple\none\ntwo\nthree\nfour\n")
 writefile("user_file", "user_file beth 1")
+writefile("interactive_file", "interactive_file beth 1")
 addfile("checkout_left.sh", "checkout_left.sh beth 1")
 addfile("checkout_right.sh", "checkout_right.sh beth 1")
 addfile("thermostat.c", "thermostat honeywell")
@@ -81,6 +90,13 @@ canonicalize("stderr")
 
 check(mtn("conflicts", "--conflicts-file=_MTN/conflicts-1", "show_first"), 0, nil, true)
 canonicalize("stderr")
+check(samefilestd("show_first-interactive", "stderr"))
+
+mkdir("_MTN/resolutions")
+check(mtn("--rcfile=merge3_hook.lua", "conflicts", "--conflicts-file=_MTN/conflicts-1", "resolve_first", "interactive", "_MTN/resolutions/interactive_file"), 0, true, nil)
+
+check(mtn("conflicts", "--conflicts-file=_MTN/conflicts-1", "show_first"), 0, nil, true)
+canonicalize("stderr")
 check(samefilestd("show_first-user", "stderr"))
 
 writefile("resolutions/user_file", "user_file merged")
@@ -99,5 +115,6 @@ check("user_file merged" == readfile("us
 check("checkout_left.sh beth 2" == readfile("checkout_left.sh"))
 check("checkout_right.sh beth 2" == readfile("checkout_right.sh"))
 check("user_file merged" == readfile("user_file"))
+check("interactive_file merged" == readfile("interactive_file"))
 
 -- end of file
============================================================
--- tests/resolve_conflicts_all_resolutions/conflicts-1	bf24db060f7d4f25c09eff14083d02b9e6a2533b
+++ tests/resolve_conflicts_all_resolutions/conflicts-1	09ae554632fc05d64f3f59b9e536380d937895eb
@@ -1,6 +1,6 @@
-    left [deb9772dea922e56623683f9fa58558670cda9a6]
-   right [670f6a2810983d1f6ce4c6c076f5f685ffd4b17c]
-ancestor [59f6060f7ed4dd514c2e0a9bd291ed9a9af29e23]
+    left [6fcbac878d4e20dc024bf16e63bd88906ac21afd]
+   right [138053fd821daa41aa98e55641d087da1d70ca2b]
+ancestor [ecceebea23b1c81b980671b4cac91ed3421396c3]
 
      conflict duplicate_name
     left_type "added file"
@@ -26,6 +26,15 @@ right_file_id [7e9f2712c5d3570815f154677
    right_name "thermostat.c"
 right_file_id [7e9f2712c5d3570815f1546772d9119474d32afc]
 
+        conflict content
+       node_type "file"
+   ancestor_name "interactive_file"
+ancestor_file_id [c0377dbf53083e56aec683b6f54790321963ac62]
+       left_name "interactive_file"
+    left_file_id [942f274ea0d3ef68b821d67f8b01f79d17cfbf8f]
+      right_name "interactive_file"
+   right_file_id [f5545d552609d36494a195deee7f9df617cb3443]
+
          conflict content
         node_type "file"
     ancestor_name "simple_file"
============================================================
--- tests/resolve_conflicts_all_resolutions/conflicts-resolved	4018b395bff3124e1d091e5c600462c88cf8ea62
+++ tests/resolve_conflicts_all_resolutions/conflicts-resolved	bbfb68dde1ac7c4394118c6efa86ef722167183b
@@ -1,6 +1,6 @@
-    left [deb9772dea922e56623683f9fa58558670cda9a6]
-   right [670f6a2810983d1f6ce4c6c076f5f685ffd4b17c]
-ancestor [59f6060f7ed4dd514c2e0a9bd291ed9a9af29e23]
+    left [6fcbac878d4e20dc024bf16e63bd88906ac21afd]
+   right [138053fd821daa41aa98e55641d087da1d70ca2b]
+ancestor [ecceebea23b1c81b980671b4cac91ed3421396c3]
 
            conflict duplicate_name
           left_type "added file"
@@ -32,6 +32,16 @@ resolved_rename_right "thermostat-honeyw
  resolved_rename_left "thermostat-westinghouse.c"
 resolved_rename_right "thermostat-honeywell.c"
 
+        conflict content
+       node_type "file"
+   ancestor_name "interactive_file"
+ancestor_file_id [c0377dbf53083e56aec683b6f54790321963ac62]
+       left_name "interactive_file"
+    left_file_id [942f274ea0d3ef68b821d67f8b01f79d17cfbf8f]
+      right_name "interactive_file"
+   right_file_id [f5545d552609d36494a195deee7f9df617cb3443]
+   resolved_user "_MTN/resolutions/interactive_file"
+
          conflict content
         node_type "file"
     ancestor_name "simple_file"
============================================================
--- tests/resolve_conflicts_all_resolutions/merge-1	4d660533ce23cbfacdc84e5fed181452a20f8b36
+++ tests/resolve_conflicts_all_resolutions/merge-1	8e3a1ba80b20c6b945ab48e83d5ce0df06720c1a
@@ -1,15 +1,16 @@ mtn: calculating best pair of heads to m
 mtn: 2 heads on branch 'testbranch'
 mtn: merge 1 / 1:
 mtn: calculating best pair of heads to merge next
-mtn: [left]  670f6a2810983d1f6ce4c6c076f5f685ffd4b17c
-mtn: [right] deb9772dea922e56623683f9fa58558670cda9a6
+mtn: [left]  138053fd821daa41aa98e55641d087da1d70ca2b
+mtn: [right] 6fcbac878d4e20dc024bf16e63bd88906ac21afd
 mtn: dropping checkout_left.sh
 mtn: replacing content of checkout_left.sh with resolutions/checkout_left.sh
 mtn: replacing content of checkout_right.sh with resolutions/checkout_right.sh
 mtn: dropping checkout_right.sh
 mtn: renaming thermostat.c to thermostat-westinghouse.c
 mtn: renaming thermostat.c to thermostat-honeywell.c
+mtn: replacing content of interactive_file, interactive_file with _MTN/resolutions/interactive_file
 mtn: merged simple_file, simple_file
 mtn: replacing content of user_file, user_file with resolutions/user_file
-mtn: [merged] 1280be5b732ba73dc73a63c5e6a77efc4f690d90
+mtn: [merged] d617fe493dc8a88bf4d5463b782208cb5e4c9768
 mtn: note: your workspaces have not been updated
============================================================
--- tests/resolve_conflicts_all_resolutions/show_first-user	abab342008177d9c3dd49edfb582f0b9f483003e
+++ tests/resolve_conflicts_all_resolutions/show_first-user	28e16e7e03af8954cbbd55b17827c92bc51f4bbf
@@ -1,3 +1,4 @@ mtn: possible resolutions:
 mtn: content user_file
 mtn: possible resolutions:
-mtn: resolve user "file_name"
+mtn: resolve_first interactive "file_name"
+mtn: resolve_first user "file_name"
============================================================
--- tests/resolve_conflicts_all_resolutions/show_remaining-checkout_left	cd1882e61df967d6ee9f21f466be8d0a03c88fb5
+++ tests/resolve_conflicts_all_resolutions/show_remaining-checkout_left	457e3d43e1c99cff6224665099b74068733ed97a
@@ -1,4 +1,5 @@ mtn: duplicate_name thermostat.c
 mtn: duplicate_name checkout_left.sh
 mtn: duplicate_name checkout_right.sh
 mtn: duplicate_name thermostat.c
+mtn: content interactive_file
 mtn: content user_file
============================================================
--- tests/resolve_conflicts_all_resolutions/show_remaining-thermostat	2bf5ad8ca1cd6a549e4bbe01c0e0440b99dabb61
+++ tests/resolve_conflicts_all_resolutions/show_remaining-thermostat	7ec8e586d80ebca3687341f78f60b0aacb329678
@@ -1,2 +1,3 @@ mtn: duplicate_name thermostat.c
 mtn: duplicate_name thermostat.c
+mtn: content interactive_file
 mtn: content user_file