On 12/14/2020 11:21 AM, Elijah Newren via GitGitGadget wrote:
> From: Elijah Newren <newren@xxxxxxxxx>
>
> Implement cases where renames are involved in type changes (i.e. the
> side of history that didn't rename the file changed its type from a
> regular file to a symlink or submodule). There was some code to handle
> this in merge-recursive but only in the special case when the renamed
> file had no content changes. The code here works differently -- it
> knows process_entry() can handle mode conflicts, so it does a few
> minimal tweaks to ensure process_entry() can just finish the job as
> needed.
>
> Signed-off-by: Elijah Newren <newren@xxxxxxxxx>
> ---
> merge-ort.c | 33 +++++++++++++++++++++++++++++++--
> 1 file changed, 31 insertions(+), 2 deletions(-)
>
> diff --git a/merge-ort.c b/merge-ort.c
> index 9aac33c8e31..11e33f56edf 100644
> --- a/merge-ort.c
> +++ b/merge-ort.c
> @@ -778,7 +778,32 @@ static int process_renames(struct merge_options *opt,
> S_ISREG(newinfo->stages[target_index].mode));
> if (type_changed && collision) {
> /* special handling so later blocks can handle this */
Perhaps drop this comment, or incorporate it into the lower one?
> - die("Not yet implemented");
> + /*
> + * if type_changed && collision are both true, then this
> + * was really a double rename, but one side wasn't
> + * detected due to lack of break detection. I.e.
> + * something like
> + * orig: has normal file 'foo'
> + * side1: renames 'foo' to 'bar', adds 'foo' symlink
> + * side2: renames 'foo' to 'bar'
> + * In this case, the foo->bar rename on side1 won't be
> + * detected because the new symlink named 'foo' is
> + * there and we don't do break detection. But we detect
> + * this here because we don't want to merge the content
> + * of the foo symlink with the foo->bar file, so we
> + * have some logic to handle this special case. The
> + * easiest way to do that is make 'bar' on side1 not
> + * be considered a colliding file but the other part
> + * of a normal rename. If the file is very different,
> + * well we're going to get content merge conflicts
> + * anyway so it doesn't hurt. And if the colliding
> + * file also has a different type, that'll be handled
> + * by the content merge logic in process_entry() too.
> + *
> + * See also t6430, 'rename vs. rename/symlink'
I appreciate the callout to a test that exercises this behavior.
> + */
> + collision = 0;
> + }
Here, we regain that closing curly brace, fixing the compiler errors from
earlier.
> if (source_deleted) {
> if (target_index == 1) {
> rename_branch = opt->branch1;
> @@ -858,7 +883,11 @@ static int process_renames(struct merge_options *opt,
> newinfo->pathnames[0] = oldpath;
> if (type_changed) {
> /* rename vs. typechange */
> - die("Not yet implemented");
> + /* Mark the original as resolved by removal */
> + memcpy(&oldinfo->stages[0].oid, &null_oid,
> + sizeof(oldinfo->stages[0].oid));
> + oldinfo->stages[0].mode = 0;
> + oldinfo->filemask &= 0x06;
This matches your explanation in the comment above. I wonder if 0x06
could be less magical, but we are really deep in the weeds here already.
Thanks,
-Stolee
