Git Commands

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Merge

Commit

Edit commit before push

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git commit --amend

Hooks

Like a real hook, Git Hook will run a specific script before or after important git actions, such as committing, rebasing, and pushing.

Where is it

All the hook files are stored in the .git/hooks:

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applypatch-msg.sample     post-update.sample        pre-merge-commit.sample   pre-receive.sample        update.sample
commit-msg.sample         pre-applypatch.sample     pre-push.sample           prepare-commit-msg.sample
fsmonitor-watchman.sample pre-commit.sample                pre-rebase.sample         push-to-checkout.sample

How to write?

Open post-update.sample; here is an example:

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#!/bin/sh
#
# An example hook script to prepare a packed repository for use over
# dumb transports.
#
# To enable this hook, rename this file to "post-update".

exec git update-server-info

Actually, not only bash script works, Python, Lua, or other script language work. Remember to add the path of exec file at the first line.

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#!/bin/sh
#!/bin/python3
#!/usr/bin/env python3

Exit Value

In some pre check, the exit value could control whether the next step will run. If exit(0) is used in the pre-commit hook, the commit will achieve success. However, if the hook exit with -1(exit(-1)), the commit will be prevented until the requirements are met. Here is an example:

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#!/usr/bin/env python3

import os

res = os.system('black ./tensor/ --check')

if res == 0:
    exit(0)
else:
    print('Some codes need to be format! please fix it.')

exit(-1)

In this example, the script uses black to check whether the code is formatted or not. If the code is unformatted, it will prevent the commit.

Usage

Remove the .sample in the file name; the hook will automatically run at a certain time.