The 'todo' sheet for interactive rebase shows abbreviated SHA-1's and then performs its operations upon those shortened values. This can lead to an abort if the SHA-1 of a reworded or edited commit is no longer unique within the abbreviated SHA-1 space and a subsequent SHA-1 in the todo list has the same abbreviated value. For example: edit f00dfad first pick badbeef second If, after editing, the new SHA-1 of "first" also has prefix badbeef, then the subsequent 'pick badbeef second' will fail since badbeef is no longer a unique SHA-1 abbreviation: error: short SHA1 badbeef is ambiguous. fatal: Needed a single revision Invalid commit name: badbeef Demonstrate this problem with a couple of specially crafted commits which initially have distinct abbreviated SHA-1's, but for which the abbreviated SHA-1's collide after a simple rewording of the first commit's message. Signed-off-by: Eric Sunshine <sunshine@xxxxxxxxxxxxxx> --- t/t3404-rebase-interactive.sh | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/t/t3404-rebase-interactive.sh b/t/t3404-rebase-interactive.sh index f857161..64a02a0 100755 --- a/t/t3404-rebase-interactive.sh +++ b/t/t3404-rebase-interactive.sh @@ -1037,4 +1037,28 @@ test_expect_success 'rebase -i with --strategy and -X' ' test $(cat file1) = Z ' +test_expect_success 'short SHA-1 setup' ' + test_when_finished "git checkout master" && + git checkout --orphan collide && + git rm -rf . && + ( + unset test_tick && + test_commit collide1 collide && + test_commit --notick collide2 collide && + test_commit --notick collide3 collide + ) +' + +test_expect_failure 'short SHA-1 collide' ' + test_when_finished "reset_rebase && git checkout master" && + git checkout collide && + ( + unset test_tick && + test_tick && + set_fake_editor && + FAKE_COMMIT_MESSAGE="collide2 ac4f2ee" \ + FAKE_LINES="reword 1 2" git rebase -i HEAD~2 + ) +' + test_done -- 1.8.4.557.g34b3a2e -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html