Merge branch 'ps/history-split'

"git history" learned the "split" subcommand.

* ps/history-split:
  builtin/history: implement "split" subcommand
  builtin/history: split out extended function to create commits
  cache-tree: allow writing in-memory index as tree
  add-patch: allow disabling editing of hunks
  add-patch: add support for in-memory index patching
  add-patch: remove dependency on "add-interactive" subsystem
  add-patch: split out `struct interactive_options`
  add-patch: split out header from "add-interactive.h"

diff --cc builtin/add.c
Simple merge

diff --cc builtin/checkout.c
index 1d1667fa4c73c87411e43af6d7424d1fdfc64a1f,f8b3a7b08ce120ad4a12db94c60d0bbd189b3f8f..e031e6188613a6ceede132f4c3fe5023af36e6e9
--- 1/builtin/checkout.c
--- 2/builtin/checkout.c
+++ b/builtin/checkout.c
@@@ -888,10 -888,11 +888,11 @@@ static int merge_working_tree(const str
                         */
  
                        add_files_to_cache(the_repository, NULL, NULL, NULL, 0,
 -                                         0);
 +                                      0, 0);
                        init_ui_merge_options(&o, the_repository);
                        o.verbosity = 0;
-                       work = write_in_core_index_as_tree(the_repository);
+                       work = write_in_core_index_as_tree(the_repository,
+                                                          the_repository->index);
  
                        ret = reset_tree(new_tree,
                                         opts, 1,

diff --cc builtin/commit.c
Simple merge

diff --cc builtin/history.c
Simple merge

diff --cc commit.h
Simple merge

diff --cc t/meson.build
index 026bf02fd6b795be7feaf3ef5e3b2b66aa87eca0,2d578ef58b516985dd8651089f6da97abf840aff..8757b295954ebe5adf1899e818451175318015cb
--- 1/t/meson.build
--- 2/t/meson.build
+++ b/t/meson.build
@@@ -393,9 -390,9 +393,10 @@@ integration_tests = 
    't3436-rebase-more-options.sh',
    't3437-rebase-fixup-options.sh',
    't3438-rebase-broken-files.sh',
 +  't3440-rebase-trailer.sh',
    't3450-history.sh',
    't3451-history-reword.sh',
+   't3452-history-split.sh',
    't3500-cherry.sh',
    't3501-revert-cherry-pick.sh',
    't3502-cherry-pick-merge.sh',