It was reported by Nazri Ramliy that ORIG_HEAD was set incorrectly again, this time caused by the shortcut to call git am directly, without detouring to a Unix shell script. Patch 2/4 might look like something completely unrelated, but without it, the update to HEAD might use an incorrect reflog message. Patch 1/4 is more a "while at it" patch; while looking which code paths might need to update ORIG_HEAD, I noticed that this reset_head() call did unnecessary work. Changes since v1: * Reworded the unclear commit message of patch 1/4. Johannes Schindelin (4): built-in rebase: no need to check out `onto` twice built-in rebase: use the correct reflog when switching branches built-in rebase: demonstrate that ORIG_HEAD is not set correctly built-in rebase: set ORIG_HEAD just once, before the rebase builtin/rebase.c | 37 +++++++++++++++++++++---------------- t/t3400-rebase.sh | 8 ++++++++ 2 files changed, 29 insertions(+), 16 deletions(-) base-commit: 21853626eac565dd42572d90724b29863f61eb3b Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-153%2Fdscho%2Frebase-am-and-orig-head-v2 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-153/dscho/rebase-am-and-orig-head-v2 Pull-Request: https://github.com/gitgitgadget/git/pull/153 Range-diff vs v1: 1: 2d99429387 ! 1: 59c3266ed5 built-in rebase: no need to check out `onto` twice @@ -4,12 +4,21 @@ In the case that the rebase boils down to a fast-forward, the built-in rebase reset the working tree twice: once to start the rebase at `onto`, - then realizing that the original HEAD was an ancestor, `reset_head()` - was called to update the original ref and to point HEAD back to it. + then realizing that the original (pre-rebase) HEAD was an ancestor and + we basically already fast-forwarded to the post-rebase HEAD, + `reset_head()` was called to update the original ref and to point HEAD + back to it. That second `reset_head()` call does not need to touch the working tree, - though, as it does not change the actual tip commit. So let's avoid that - unnecessary work. + though, as it does not change the actual tip commit (and therefore the + working tree should stay unchanged anyway): only the ref needs to be + updated (because the rebase detached the HEAD, and we want to go back to + the branch on which the rebase was started). + + But that second `reset_head()` was called without the flag to leave the + working tree alone (the reason: when that call was introduced, that flag + was not yet even thought of). Let's avoid that unnecessary work by + passing that flag. Signed-off-by: Johannes Schindelin <johannes.schindelin@xxxxxx> 2: b92d76065d = 2: 67e41c032a built-in rebase: use the correct reflog when switching branches 3: 1bc3cbad26 = 3: 17737998f4 built-in rebase: demonstrate that ORIG_HEAD is not set correctly 4: 1786c172ef = 4: 7891c05f51 built-in rebase: set ORIG_HEAD just once, before the rebase -- gitgitgadget
