Question

It’s kind weird, but I can’t fulfill a pretty common operation with git. Basically what I want is to checkout a feature branch, not using it’s head but using SHA id. This SHA points between merges from master branch.

The problem is that all I get is just master branch without a commits from feature branch.
Currently I’m trying to fix a regression introduced earlier in master branch.

Just to be more descriptive, I crafted a small bash script to recreate a problem repository:

#!/bin/bash

rm -rf ./.git
git init

echo "test1" > test1.txt
git add test1.txt
git commit -m "test1" -a

git checkout -b patches master

echo "test2" > test2.txt
git add test2.txt
git commit -m "test2" -a

git checkout master

echo "test3" > test3.txt
git add test3.txt
git commit -m "test3" -a

echo "test4" > test4.txt
git add test4.txt
git commit -m "test4" -a

echo "test5" > test5.txt
git add test5.txt
git commit -m "test5" -a

git checkout patches
git merge master    

#Now how to get a branch having all commits from patches + test3.txt + test4.txt - test5.txt ???

Basically all I want is just to checkout branch “patches” with files 1-4, but not including test5.txt.

Doing:
git checkout [sha_where_test4.txt_entered]

… just gives a branch with test1,test3,test4, but excluding test2.txt

More complex example:

#!/bin/bash

rm -rf ./.git
git init

echo "test1" > test1.txt
git add test1.txt
git commit -m "test1" -a

git checkout -b patches master

echo "test2" > test2.txt
git add test2.txt
git commit -m "test2" -a

git checkout master

echo "test3" > test3.txt
git add test3.txt
git commit -m "test3" -a

echo "test4" > test4.txt
git add test4.txt
git commit -m "test4" -a

echo "test5" > test5.txt
git add test5.txt
git commit -m "test5" -a

git checkout patches
git merge master

echo "test6" > test6.txt
git add test6.txt
git commit -m "test6" -a

#Now how to get a branch having all commits from patches + test3.txt + test4.txt - test5.txt ???
git log --topo-order | cat

# Now I need something to help me going back to history 
# without manually calculating that patches~2 sha's
git checkout -b patches.tmp master~1
git merge patches~2

Thanks.

Answer 1

Regarding your first example, you need to replay test3 and 4 on top of test2: this is a classic case of rebase --onto:

Start from:

alt text http://img169.imageshack.us/img169/2255/gitr1.png

Mark the current patches emplacement, and move the patches branch where you would like to end (test4):

C:\Prog\Git\tests\rep\main>git checkout patches
Switched to branch 'patches'

C:\Prog\Git\tests\rep\main>git checkout -b tmp
Switched to a new branch 'tmp'

C:\Prog\Git\tests\rep\main>git checkout patches
Switched to branch 'patches'

C:\Prog\Git\tests\rep\main>git reset --hard master~1
HEAD is now at 8448d0f test4

That gives you:

alt text http://img169.imageshack.us/img169/4826/gitr2.png

And just rebase onto what you want the correct sequence of commits:

C:\Prog\Git\tests\rep\main>git checkout tmp
Switched to branch 'tmp'

C:\Prog\Git\tests\rep\main>git rebase --onto tmp tmp~1 patches
First, rewinding head to replay your work on top of it...
Applying: test3
Applying: test4

Which gives:

alt text http://img52.imageshack.us/img52/372/gitr3.png

That only works for linear set of commits to be moved around.