Understanding the diff between two branches in a pull request ?

[Borat Sagdiyev]

Say that a pull request is created in bit bucket to merge branch-2 into branch-1. The pull request has a diff tab to show the difference between these branches. I'd like to know the order of the comparison in the diff tab. Is it like git branch-1 branch-2, OR is it git branch-2 branch-1 ? Thanks.

[Daniil Penkin · Accepted solution]

Hello @Borat Sagdiyev,

Thanks for reaching out.

It is neither of these commands, actually. In a pull request Bitbucket shows the difference between the potential merge state and the target branch. Here's a nice blog post describing this and the reasons behind (it is almost 5 years old now but still totally valid).

So the pseudo command is rather something like this:

git diff branch-1 <merge of branch-1 and branch-2>

Does this make sense? Let me know if you have any questions.

Cheers,
Daniil 

[Borat Sagdiyev]

Thanks @Daniil Penkin - I have a pull request in bit bucket in which all lines of many files appear as changed (in bit bucket and source tree). When I use "git diff branch-1 branch-2", I see that each line has a "^M" character at the end. Hence, it appears as if there are many changes when there is essentially no change. I want to know which branch added the "^M" character, which is why I asked this question. So, can we say that branch-2 has introduced the "^M" character ?

[Daniil Penkin]

If the diff shows ^M in the added line (marked with a + and highlighted with green color) and not in the removed line (marked with a - and highlighted with red color), – then yes, that character was added in one of the commits on the branch-2.

You can also switch to the side-by-side diff which might surface in a cleaner way.

^M is the carriage return character from Windows end-of-line sequence. Git client can be configured to handle this on the fly.

Hope this helps.

Cheers,
Daniil