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[RFC PATCH 05/35] fast-forward: add advice for novices

From
Felipe Contreras <felipe.contreras@gmail.com>
Date
Jul 5, 2021, 12:31 UTC
Message-ID
<20210705123209.1808663-6-felipe.contreras@gmail.com>
In-Reply-To
<20210705123209.1808663-1-felipe.contreras@gmail.com>
It doesn't hurt showing it on `git merge --ff-only` too.
Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
---
 advice.c        | 11 +++++++++++
 advice.h        |  1 +
 builtin/merge.c |  4 +++-
 3 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/advice.c b/advice.c
index 0b9c89c48a..8f068c8be9 100644
--- a/advice.c
+++ b/advice.c
@@ -326,3 +326,14 @@ void detach_advice(const char *new_name)
 
 	fprintf(stderr, fmt, new_name);
 }
+
+void diverging_advice(void)
+{
+	advise(_("Diverging branches can't be fast-forwarded, you need to either:\n"
+		"\n"
+		"\tgit merge\n"
+		"\n"
+		"or:\n"
+		"\n"
+		"\tgit rebase\n"));
+}
diff --git a/advice.h b/advice.h
index bd26c385d0..6ce967c962 100644
--- a/advice.h
+++ b/advice.h
@@ -97,5 +97,6 @@ void NORETURN die_resolve_conflict(const char *me);
 void NORETURN die_conclude_merge(void);
 void advise_on_updating_sparse_paths(struct string_list *pathspec_list);
 void detach_advice(const char *new_name);
+void diverging_advice(void);
 
 #endif /* ADVICE_H */
diff --git a/builtin/merge.c b/builtin/merge.c
index e396943d37..1836f98f82 100644
--- a/builtin/merge.c
+++ b/builtin/merge.c
@@ -1625,8 +1625,10 @@ static int merge_common(int argc, const char **argv, const char *prefix,
 		}
 	}
 
-	if (fast_forward == FF_ONLY)
+	if (fast_forward == FF_ONLY) {
+		diverging_advice();
 		die(_("unable to fast-forward"));
+	}
 
 	if (autostash)
 		create_autostash(the_repository,
-- 
2.32.0.36.g70aac2b1aa
Previous: Felipe ContrerasNext: Ævar Arnfjörð Bjarmason
Message 17 of 53 in “git update: fix broken git pull”
  1. 00/35 git update: fix broken git pullFelipe Contreras, Jul 5, 2021
  2. 01/35 merge: improve fatal fast-forward messageFelipe Contreras, Jul 5, 2021
  3. Ævar Arnfjörð BjarmasonJul 6, 2021
  4. Felipe ContrerasJul 6, 2021
  5. Randall S. BeckerJul 6, 2021
  6. Junio C HamanoJul 6, 2021
  7. Felipe ContrerasJul 6, 2021
  8. Randall S. BeckerJul 6, 2021
  9. Junio C HamanoJul 6, 2021
  10. Randall S. BeckerJul 6, 2021
  11. Felipe ContrerasJul 6, 2021
  12. Randall S. BeckerJul 6, 2021
  13. Felipe ContrerasJul 6, 2021
  14. 02/35 merge: split cmd_merge()Felipe Contreras, Jul 5, 2021
  15. 03/35 fast-forward: add new builtinFelipe Contreras, Jul 5, 2021
  16. 04/35 doc: fast-forward: explain what it isFelipe Contreras, Jul 5, 2021
  17. 05/35 fast-forward: add advice for novicesFelipe Contreras, Jul 5, 2021
  18. Ævar Arnfjörð BjarmasonJul 6, 2021
  19. Felipe ContrerasJul 6, 2021
  20. 06/35 fast-forward: make the advise configurableFelipe Contreras, Jul 5, 2021
  21. 07/35 fast-forward: add help about merge vs. rebaseFelipe Contreras, Jul 5, 2021
  22. 08/35 update: new built-inFelipe Contreras, Jul 5, 2021
  23. 09/35 update: add options and usage skeletonFelipe Contreras, Jul 5, 2021
  24. 10/35 update: add --ff optionFelipe Contreras, Jul 5, 2021
  25. Ævar Arnfjörð BjarmasonJul 6, 2021
  26. Felipe ContrerasJul 6, 2021
  27. 11/35 update: add --merge modeFelipe Contreras, Jul 5, 2021
  28. Ævar Arnfjörð BjarmasonJul 6, 2021
  29. Felipe ContrerasJul 6, 2021
  30. 12/35 commit: support for multiple MERGE_MODEFelipe Contreras, Jul 5, 2021
  31. 13/35 merge: add --reverse-parents optionFelipe Contreras, Jul 5, 2021
  32. 14/35 update: reverse the order of parentsFelipe Contreras, Jul 5, 2021
  33. 15/35 update: fake a reverse order of parents in messageFelipe Contreras, Jul 5, 2021
  34. 16/35 update: add --rebase modeFelipe Contreras, Jul 5, 2021
  35. 17/35 update: add mode configuationFelipe Contreras, Jul 5, 2021
  36. 18/35 update: add per-branch mode configurationFelipe Contreras, Jul 5, 2021
  37. 19/35 pull: cleanup autostash checkFelipe Contreras, Jul 5, 2021
  38. 20/35 pull: trivial cleanupFelipe Contreras, Jul 5, 2021
  39. 21/35 pull: trivial whitespace style fixFelipe Contreras, Jul 5, 2021
  40. 22/35 pull: introduce --merge optionFelipe Contreras, Jul 5, 2021
  41. 23/35 rebase: add REBASE_DEFAULTFelipe Contreras, Jul 5, 2021
  42. 24/35 pull: move configuration fetchesFelipe Contreras, Jul 5, 2021
  43. 25/35 pull: show warning with --ff optionsFelipe Contreras, Jul 5, 2021
  44. 26/35 pull: add pull.modeFelipe Contreras, Jul 5, 2021
  45. 27/35 pull: add per-branch mode configurationFelipe Contreras, Jul 5, 2021
  46. 28/35 pull: add pull.mode=fast-forwardFelipe Contreras, Jul 5, 2021
  47. 29/35 pull: reorganize mode conditionalsFelipe Contreras, Jul 5, 2021
  48. 30/35 pull: add diverging advice on fast-forward modeFelipe Contreras, Jul 5, 2021
  49. 31/35 pull: improve --rebase and pull.rebase interactionFelipe Contreras, Jul 5, 2021
  50. 32/35 pull: improve default warningFelipe Contreras, Jul 5, 2021
  51. 33/35 pull: advice of future changesFelipe Contreras, Jul 5, 2021
  52. 34/35 FUTURE: pull: enable ff-only mode by defaultFelipe Contreras, Jul 5, 2021
  53. 35/35 !fixup FUTURE: pull: enable ff-only mode by defaultFelipe Contreras, Jul 5, 2021

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