[PATCH 0/7] Fix and improve some error codepaths in merge-ort

This series started as a just a fix for the abort hit in merge-ort when custom merge drivers error out (see https://lore.kernel.org/git/75F8BD12-7743-4863-B4C5-049FDEC4645E@gearset.com/). However, while working on that, I found a few other issues around error codepaths in merge-ort. So this series:

 * Patches 1-2: fix the reported abort problem
 * Patches 3-4: make code in handle_content_merges() easier to handle when
   we hit errors
 * Patch 5: fix a misleading comment
 * Patches 6-7: make error handling (immediate print vs. letting callers get
   the error information) more consistent

The last two patches change the behavior slightly for error codepaths, and there's a question about whether we should show only the error messages that caused an early termination of the merge, or if we should also show any conflict messages for other paths that were handled before we hit the early termination. These patches made a decision but feel free to take those last two patches as more of an RFC.

Elijah Newren (7):
  merge-ort: extract handling of priv member into reusable function
  merge-ort: maintain expected invariant for priv member
  merge-ort: fix type of local 'clean' var in handle_content_merge()
  merge-ort: clearer propagation of failure-to-function from
    merge_submodule
  merge-ort: loosen commented requirements
  merge-ort: upon merge abort, only show messages causing the abort
  merge-ort: convert more error() cases to path_msg()

 merge-ort.c           | 167 +++++++++++++++++++++++++++++++-----------
 t/t6406-merge-attr.sh |  42 ++++++++++-
 2 files changed, 164 insertions(+), 45 deletions(-)

base-commit: 8d94cfb54504f2ec9edc7ca3eb5c29a3dd3675ae
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1748%2Fnewren%2Ffix-error-cases-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1748/newren/fix-error-cases-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/1748