merge-ort: add implementation of rename/delete conflicts

Implement rename/delete conflicts, i.e. one side renames a file and the
other deletes the file.  This code replaces the following from
merge-recurisve.c:

  * the code relevant to RENAME_DELETE in process_renames()
  * the RENAME_DELETE case of process_entry()
  * handle_rename_delete()

Also, there is some shared code from merge-recursive.c for multiple
different rename cases which we will no longer need for this case (or
other rename cases):

  * handle_change_delete()
  * setup_rename_conflict_info()

The consolidation of five separate codepaths into one is made possible
by a change in design: process_renames() tweaks the conflict_info
entries within opt->priv->paths such that process_entry() can then
handle all the non-rename conflict types (directory/file, modify/delete,
etc.) orthogonally.  This means we're much less likely to miss special
implementation of some kind of combination of conflict types (see
commits brought in by 66c62eaec6 ("Merge branch 'en/merge-tests'",
2020-11-18), especially commit ef52778708 ("merge tests: expect improved
directory/file conflict handling in ort", 2020-10-26) for more details).
That, together with letting worktree/index updating be handled
orthogonally in the merge_switch_to_result() function, dramatically
simplifies the code for various special rename cases.

To be fair, there is a _slight_ tweak to process_entry() here, because
rename/delete cases will also trigger the modify/delete codepath.
However, we only want a modify/delete message to be printed for a
rename/delete conflict if there is a content change in the renamed file
in addition to the rename.  So process_renames() and process_entry()
aren't quite fully orthogonal, but they are pretty close.

Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Elijah Newren 2020-12-15 18:28:03 +00:00 committed by Junio C Hamano
parent 53e88a0353
commit 2e91ddd24e

View file

@ -657,6 +657,7 @@ static int process_renames(struct merge_options *opt,
unsigned int old_sidemask;
int target_index, other_source_index;
int source_deleted, collision, type_changed;
const char *rename_branch = NULL, *delete_branch = NULL;
old_ent = strmap_get_entry(&opt->priv->paths, pair->one->path);
oldpath = old_ent->key;
@ -779,6 +780,15 @@ static int process_renames(struct merge_options *opt,
/* special handling so later blocks can handle this */
die("Not yet implemented");
}
if (source_deleted) {
if (target_index == 1) {
rename_branch = opt->branch1;
delete_branch = opt->branch2;
} else {
rename_branch = opt->branch2;
delete_branch = opt->branch1;
}
}
assert(source_deleted || oldinfo->filemask & old_sidemask);
@ -790,13 +800,26 @@ static int process_renames(struct merge_options *opt,
/* rename/add/delete or rename/rename(2to1)/delete */
die("Not yet implemented");
} else {
/* a few different cases... */
/*
* a few different cases...start by copying the
* existing stage(s) from oldinfo over the newinfo
* and update the pathname(s).
*/
memcpy(&newinfo->stages[0], &oldinfo->stages[0],
sizeof(newinfo->stages[0]));
newinfo->filemask |= (1 << MERGE_BASE);
newinfo->pathnames[0] = oldpath;
if (type_changed) {
/* rename vs. typechange */
die("Not yet implemented");
} else if (source_deleted) {
/* rename/delete */
die("Not yet implemented");
newinfo->path_conflict = 1;
path_msg(opt, newpath, 0,
_("CONFLICT (rename/delete): %s renamed"
" to %s in %s, but deleted in %s."),
oldpath, newpath,
rename_branch, delete_branch);
} else {
/* normal rename */
die("Not yet implemented");
@ -1332,12 +1355,21 @@ static void process_entry(struct merge_options *opt,
modify_branch = (side == 1) ? opt->branch1 : opt->branch2;
delete_branch = (side == 1) ? opt->branch2 : opt->branch1;
path_msg(opt, path, 0,
_("CONFLICT (modify/delete): %s deleted in %s "
"and modified in %s. Version %s of %s left "
"in tree."),
path, delete_branch, modify_branch,
modify_branch, path);
if (ci->path_conflict &&
oideq(&ci->stages[0].oid, &ci->stages[side].oid)) {
/*
* This came from a rename/delete; no action to take,
* but avoid printing "modify/delete" conflict notice
* since the contents were not modified.
*/
} else {
path_msg(opt, path, 0,
_("CONFLICT (modify/delete): %s deleted in %s "
"and modified in %s. Version %s of %s left "
"in tree."),
path, delete_branch, modify_branch,
modify_branch, path);
}
} else if (ci->filemask == 2 || ci->filemask == 4) {
/* Added on one side */
int side = (ci->filemask == 4) ? 2 : 1;