21 December 2020 1 comment Python
I love git on the command line and I actually never use a GUI to navigate git branches. But sometimes, I need scripting to make abstractions that make life more convenient. What often happens is that I need to go back to the "main" branch. I write main in quotation marks because it's not always called main. Sometimes it's called master. And it's tedious to have to remember which one is the default. So I wrote a script called Gcm.
#!/usr/bin/env python
import subprocess
def run(*args):
default_branch = get_default_branch()
current_branch = get_current_branch()
if default_branch != current_branch:
checkout_branch(default_branch)
else:
print(f"Already on {default_branch}")
return 1
def checkout_branch(branch_name):
subprocess.run(f"git checkout {branch_name}".split())
def get_default_branch():
origin_name = "origin"
res = subprocess.run(
f"git remote show {origin_name}".split(), check=True, capture_output=True,
)
for line in res.stdout.decode("utf-8").splitlines():
if line.strip().startswith("HEAD branch:"):
return line.replace("HEAD branch:", "").strip()
raise NotImplementedError(f"No remote called {origin_name!r}")
def get_current_branch():
res = subprocess.run("git branch --show-current".split(), capture_output=True)
for line in res.stdout.decode("utf-8").splitlines():
return line.strip()
raise NotImplementedError("Don't know what to do!")
if __name__ == "__main__":
import sys
sys.exit(run(*sys.argv[1:]))
It ain't pretty or a spiffy one-liner, but it works. It assumes that the repo has a remote called origin which doesn't matter if it's the upstream or your fork. Put this script into a file called ~/bin/Gcm and run chmox +x ~/bin/Gcm.
Now, whenever I want to go back to the main branch I type Gcm and it takes me there.
It might seem silly, and it might not be for you, but I love it and use it many times per day. Perhaps by sharing this tip, it'll inspire someone else to set up something similar for themselves.
I have a pattern (or rule?) that all scripts that I write myself are always capitalized like that. It avoids clashes with stuff I install with brew
or other bash/zsh aliases.
For example:
ls -l ~/bin/RemoteVSCodePeterbecom.sh ls -l ~/bin/Cleanupfiles ls -l ~/bin/RandomString.py
Thank you for sharing this cool tool.
I had to adapt it a little bit because I am using German language settings where `HEAD branch` is called `Hauptbranch`.
It's a shame that git makes it so complicated to find out about the head branch.