git/list[1] front-page[2] threads[3] people[4] search[5] about
 

[PATCH 01/16] bisect: write about `bisect next` in documentation

From
Stephan Beyer <s-beyer@gmx.net>
Date
Feb 26, 2016, 02:04 UTC
Message-ID
<1456452282-10325-2-git-send-email-s-beyer@gmx.net>
In-Reply-To
<1456452282-10325-1-git-send-email-s-beyer@gmx.net>

Mention `bisect next` in the documentation of bisect. `bisect next` is only useful in rare cases and the result can also be accomplished using other utilities (like reflog). However, it is available as a bisect command and should hence be documented.

Also mention the use case when no good commit is known. Some user message in git-bisect.sh is changed to reflect that use case. It is also simplified: there is no need to mention running `bisect start` explicitly, because it can be done indirectly using `bisect bad`.

Signed-off-by: Stephan Beyer <s-beyer@gmx.net>
---

This patch considers the source code comment that says to be "not sure we want 'next' at the UI level anymore", and replies with "Yes, we want it!". Therefore, the "git bisect next" functionality is explicitly motivated and documented.

The motivation of "having no good commit" is not made up. I am working on a big project that is several years old and nearly no test exists. So I add a test and things go wrong. However, I know from using (an older version of) the project that a similar case did work. So...I want to find the bad commit... However, to make git bisect work, I always first had to find a good commit, so I ended up doing the whole bisection process manually (because I did not know that "git bisect next" existed).

I think that this change will help people who are also in these situations.

 Documentation/git-bisect.txt | 25 +++++++++++++++++++++++++
 git-bisect.sh                | 15 ++++-----------
 2 files changed, 29 insertions(+), 11 deletions(-)
diff --git a/Documentation/git-bisect.txt b/Documentation/git-bisect.txt
index 7e79aae..8045e6d 100644
--- a/Documentation/git-bisect.txt
+++ b/Documentation/git-bisect.txt
@@ -27,6 +27,7 @@ on the subcommand:
  git bisect replay <logfile>
  git bisect log
  git bisect run <cmd>...
+ git bisect next
  git bisect help
 
 This command uses a binary search algorithm to find which commit in
@@ -66,6 +67,15 @@ checks it out, and outputs something similar to the following:
 Bisecting: 675 revisions left to test after this (roughly 10 steps)
 ------------------------------------------------
 
+Note that in cases you do not know a good commit,
+you can also start with:
+
+------------------------------------------------
+$ git bisect start
+$ git bisect bad                 # current version is bad
+$ git bisect next                # check out another commit
+------------------------------------------------
+
 You should now compile the checked-out version and test it. If that
 version works correctly, type
 
@@ -353,6 +363,21 @@ rewind the tree to the pristine state.  Finally the script should exit
 with the status of the real test to let the `git bisect run` command loop
 determine the eventual outcome of the bisect session.
 
+Bisect next
+~~~~~~~~~~~
+
+Sometimes it can be necessary to check out other branches during a bisect
+session. If you want to check out the next commit of the bisection again,
+simply issue the command:
+
+------------
+$ git bisect next
+------------
+
+Another typical use case of this command is when you have marked a commit
+as bad but you do not know a good commit. Instead of crawling through the
+history yourself, let this command check out a commit for you.
+
 OPTIONS
 -------
 --no-checkout::
diff --git a/git-bisect.sh b/git-bisect.sh
index 5d1cb00..5c93a27 100755
--- a/git-bisect.sh
+++ b/git-bisect.sh
@@ -334,16 +334,10 @@ bisect_next_check() {
 	*)
 		bad_syn=$(bisect_voc bad)
 		good_syn=$(bisect_voc good)
-		if test -s "$GIT_DIR/BISECT_START"
-		then
-
-			eval_gettextln "You need to give me at least one \$bad_syn and one \$good_syn revision.
-(You can use \"git bisect \$bad_syn\" and \"git bisect \$good_syn\" for that.)" >&2
-		else
-			eval_gettextln "You need to start by \"git bisect start\".
-You then need to give me at least one \$good_syn and one \$bad_syn revision.
-(You can use \"git bisect \$bad_syn\" and \"git bisect \$good_syn\" for that.)" >&2
-		fi
+		eval_gettextln "You need to give me at least one \$bad_syn revision.
+Use \"git bisect \$bad_syn\" for that. One \$good_syn revision is also helpful
+for bisecting (use \"git bisect \$good_syn\"). If you do not know one \$good_syn
+revision, you can use \"git bisect next\" to find one." >&2
 		exit 1 ;;
 	esac
 }
@@ -677,7 +671,6 @@ case "$#" in
 	skip)
 		bisect_skip "$@" ;;
 	next)
-		# Not sure we want "next" at the UI level anymore.
 		bisect_next "$@" ;;
 	visualize|view)
 		bisect_visualize "$@" ;;
-- 
2.7.1.354.gd492730.dirty
Previous: Stephan BeyerNext: Jacob Keller
Message 2 of 34 in “git bisect improvements”
  1. 00/16 git bisect improvementsStephan Beyer, Feb 26, 2016
  2. 01/16 bisect: write about `bisect next` in documentationStephan Beyer, Feb 26, 2016
  3. Jacob KellerFeb 26, 2016
  4. Junio C HamanoFeb 26, 2016
  5. Stephan BeyerFeb 27, 2016
  6. Junio C HamanoFeb 27, 2016
  7. Stephan BeyerFeb 27, 2016
  8. Junio C HamanoFeb 28, 2016
  9. 02/16 bisect: add test for the bisect algorithmStephan Beyer, Feb 26, 2016
  10. Christian CouderFeb 26, 2016
  11. Stephan BeyerFeb 26, 2016
  12. Christian CouderFeb 27, 2016
  13. Matthieu MoyFeb 27, 2016
  14. 03/16 bisect: make bisect compile if DEBUG_BISECT is setStephan Beyer, Feb 26, 2016
  15. 04/16 bisect: make algorithm behavior independent of DEBUG_BISECTStephan Beyer, Feb 26, 2016
  16. 05/16 bisect: get rid of recursion in count_distance()Stephan Beyer, Feb 26, 2016
  17. 06/16 bisect: use struct node_data array instead of int arrayStephan Beyer, Feb 26, 2016
  18. 07/16 bisect: replace clear_distance() by unique markersStephan Beyer, Feb 26, 2016
  19. 08/16 bisect: use commit instead of commit list as arguments when appropriateStephan Beyer, Feb 26, 2016
  20. Junio C HamanoFeb 26, 2016
  21. 09/16 bisect: extract get_distance() function from code duplicationStephan Beyer, Feb 26, 2016
  22. 10/16 bisect: introduce distance_direction()Stephan Beyer, Feb 26, 2016
  23. 11/16 bisect: make total number of commits globalStephan Beyer, Feb 26, 2016
  24. 12/16 bisect: rename count_distance() to compute_weight()Stephan Beyer, Feb 26, 2016
  25. 13/16 bisect: prepare for different algorithms based on find_allStephan Beyer, Feb 26, 2016
  26. 14/16 bisect: use a modified breadth-first search to find relevant weightsStephan Beyer, Feb 26, 2016
  27. Junio C HamanoFeb 26, 2016
  28. Stephan BeyerFeb 26, 2016
  29. 15/16 bisect: compute best bisection in compute_relevant_weights()Stephan Beyer, Feb 26, 2016
  30. 16/16 bisect: get back halfway shortcutStephan Beyer, Feb 26, 2016
  31. Pranit BauvaMar 20, 2016
  32. Stephan BeyerMar 21, 2016
  33. Christian CouderMar 22, 2016
  34. Pranit BauvaMar 22, 2016

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.