Gitea: The /compare/x...y page now displays diff from the merge-base to y instead of from x to y

Created on 28 Jul 2020 · 11Comments · Source: go-gitea/gitea

To reproduce:

$ git init repo && cd repo
Initialized empty Git repository in /home/vladimir/tmp/2020-07-28/repo/.git/

$ echo a > file.txt

$ git add . && git commit -m 'Initial commit'
[master (root-commit) 4b97f6e] Initial commit
 1 file changed, 1 insertion(+)
 create mode 100644 file.txt

$ echo b > file.txt

$ git commit -am 'b'
[master a9e140c] b
 1 file changed, 1 insertion(+), 1 deletion(-)

$ git checkout -b c 'HEAD^'
Switched to a new branch 'c'

$ echo c > file.txt

$ git commit -am 'c'
[c 80241e1] c
 1 file changed, 1 insertion(+), 1 deletion(-)

$ git push gitea master c
[...]

$ xdg-open https://..../compare/$(git rev-parse master)...$(git rev-parse c)

Visiting the compare URL with the SHA-1s of the two diverging branches shows the diff from their common ancestor to c, instead of from master to c.

This is a regression: this feature worked in 1.8.3 and stopped working in 1.9.6. It was extremely useful for viewing the diff from before and after a force-push.

I noticed that the URL syntax has three periods, and the new behavior thus matches git-diff's behavior when also using x...y (three periods - "symmetric difference"). Perhaps Gitea should support /compare/x..y (two periods) to do the same as the old behavior (direct diff from x to y)?

kinbug

Source

CyberShadow

Most helpful comment

Worth mentioning is that GitHub follows Git's syntax convention in its URLs:

https://www.github.com/CyberShadow/gitea12349/compare/master..c <- two dots - direct compare from master to c
https://www.github.com/CyberShadow/gitea12349/compare/master...c <- three dots - compare merge-base of the two refs to c

Gitea could follow the same convention by adding the two-dot URL variant (or rather, restoring the pre-1.9 behavior with that URL syntax).

CyberShadow on 28 Sep 2020

👍2

All 11 comments

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