CODEWITHSUNDEEP
git
ire_and_curses
ire_and_curses

Reputation: 70250

Disallowing branching from a branch in git

In my workflow I almost never want to branch from a branch other than master. A couple of times I have done this by accident when starting a new feature. When I do, it screws up my history when merging.

What's a good way to protect myself from creating a new branch if I am already on a branch? I know about the second parameter to git branch

git checkout -b newbranch master

but I'm not sure I can retrain myself to always provide it. Ideally I would have this be the default behaviour when I type git checkout -b newbranch, or have a warning when I attempt to branch from a branch.

Upvotes: 1

Views: 86

Answers (2)

Will Bickford
Will Bickford

Reputation: 5386

You can create a bash alias for git that checks for this condition and rewrites your checkout command to follow your convention. In this example below, I preserve a passed in parent branch, but default to master when one is not given.

Bash Alias

#!/bin/bash
cmd=$1
opt=$2
branch=$3
parent=$4
if [[ $cmd = "checkout" ]] && [[ $opt = "-b" ]]; then
  if [ -z "$parent" ]; then
    parent="master"
  fi
  /usr/bin/git checkout -b $branch $parent
else
  /usr/bin/git "$@"
fi

Test Command Sequence

chmod +x /path/to/git-wrapper.sh
alias git=/path/to/git-wrapper.sh
mkdir test
cd ./test
git init
echo "First line" >readme.md
git add readme.md
git commit -m "Initial commit"
git checkout -b test1
echo "Second line" >> readme.md
git commit -am "Second line"
git checkout -b test2
echo "Third line" >> readme.md
git commit -am "Third line"
git checkout master
git branch -a
git log
git merge test1
git merge test2

Example Output

Initialized empty Git repository in ...
[master (root-commit) 11bd292] Initial commit
 1 file changed, 1 insertion(+)
 create mode 100644 readme.md
Switched to a new branch 'test1'
[test1 4ace272] Second line
 1 file changed, 1 insertion(+)
Switched to a new branch 'test2'
[test2 54b7fff] Third line
 1 file changed, 1 insertion(+)
Switched to branch 'master'
* master
  test1
  test2
Updating 11bd292..4ace272
Fast-forward
 readme.md | 1 +
 1 file changed, 1 insertion(+)
Auto-merging readme.md
CONFLICT (content): Merge conflict in readme.md
Automatic merge failed; fix conflicts and then commit the result.

A merge failure is our expected result (if the alias were not active, we would have branched from test1 to test2 and the merge would have been fast-forwarded. Test it out!

Upvotes: 1

tmaj
tmaj

Reputation: 35155

I'd have a custom batch/alias that switched to master, maybe pulled master, etc, and then created a new branch.

Another option would be to create branches in your remote repo first. I don't know what solution you're using for your remote repo but this way the process would be more conscious.

Upvotes: 0

Related Questions