This is me when I realize I've been committing in the wrong branch all day:

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Fortunately, there is a way to move changesets between branches, provided you haven't pushed your changes out to any other repositories. If you have pushed your changes out to the mothership repository, or your coworkers, the only way to pick up the pieces is to get all the users of the repo together and coordinate. That is beyond to scope of this article, and too hard for all but the smallest or dictatorial teams.

Problem Setup

Here at Reci-p.com we make recipes and sell advertising. I've been hard at work writing up new recipes. Here's what I start with:

$ hg history changeset: 1:b1c330d2ac79 user: Gunnar Gissel <gunnar@reci-p.com> date: Sat Feb 04 05:15:00 2017 -0900 summary: Added quesadilla recipe changeset: 0:6f5ef8f77a9f user: Gunnar Gissel <gunnar@reci-p.com> date: Sat Jan 28 11:30:00 2017 -0900 summary: Added taco recipe 

I want to add drink recipes, but they aren't ready to show to our valuable users, so I want to add them in a development branch. Unfortunately, I've been out all night sampling drink recipes and I forget to create the new branch!

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This is what I end up with:

$ hg history changeset: 3:398dfc004270 user: Gunnar Gissel <gunnar@reci-p.com> date: Sat Feb 04 05:15:00 2017 -0900 summary: Added michela recipe changeset: 2:852364587134 user: Gunnar Gissel <gunnar@reci-p.com> date: Sat Feb 04 05:15:00 2017 -0900 summary: Added mojito recipe changeset: 1:b1c330d2ac79 user: Gunnar Gissel <gunnar@reci-p.com> date: Sat Feb 04 05:15:00 2017 -0900 summary: Added quesadilla recipe changeset: 0:6f5ef8f77a9f user: Gunnar Gissel <gunnar@reci-p.com> date: Sat Jan 28 11:30:00 2017 -0900 summary: Added taco recipe 

Fortunately, before I push all my code to the mothership repo, I notice I've been working in the wrong branch.

Move My Code to a Different Branch

The approach to fixing this problem is to create the missing branch, then create a patch from my new changesets, apply the patch to the new branch, then strip off the changesets from the incorrect branch.

Working in the same repository as above:

$ hg export -o patch.diff 3 2 

I create a patch, which shows up as a file called patch.diff.

Create a branch off the newest changeset before I started adding new stuff:

$ hg update 1 $ hg branch drinks $ hg commit 

Patch the new branch I just made:

$ hg import patch.diff 

This is dangerous, so make sure you are targeting the correct changeset. You can't easily undo this. You also need to have the strip extension enabled

Remove the changes off the original branch, so we can avoid mixing drink and food recipes:

$ hg strip 3 

Phew, my repository is fixed. Now when look at the history I can see that I've got everything in the correct branch:

$ hg history -l 4 changeset: 4:8afca56c4940 branch: drinks tag: tip user: Gunnar Gissel <gunnar@reci-p.com> date: Sat Feb 04 05:15:00 2017 -0900 summary: Added michela recipe changeset: 3:357ff9545db branch: drinks user: Gunnar Gissel <gunnar@reci-p.com> date: Sat Feb 04 05:15:00 2017 -0900 summary: Added mojito recipe changeset: 2:357ff9545db branch: drinks user: Gunnar Gissel <gunnar@reci-p.com> date: Sat Feb 04 05:15:00 2017 -0900 summary: drinks branch changeset: 1:b1c330d2ac79 user: Gunnar Gissel <gunnar@reci-p.com> date: Sat Feb 04 05:15:00 2017 -0900 summary: Added quesadilla recipe 

Now I'm safe to push and I won't accidentally pollute our recipes with drink mixing recipes

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If you like this, visit my blog for more.

Thank you Michael Budde for the header photo

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