git - Prevent user from doing a commit before pulling latest changes -

lets have following local repository commit tree when created feature branch f develop:

master -->             \              \       develop c                 \                 \          feature f 

now after sometime new features has been merged develop c , commit tree looks this:

 master -->              \               \        develop c --> d --> e                 \                  \           feature f 

now want ensure not commit before pulling latest changes develop.

master -->             \              \       develop c --> d --> e                            \                              \                       feature f 

from have tried, 1 way push changes f , try merge f develop e (now have new changes). doing throw error messages git saying develop ahead of f.i confident can done post-hook. but, can git pre-hook ?

if so, how , if not please suggest other way of doing it. if possible please explain commands doing?( beginner in git )

the requirement display custom message in case user tries this.

thanks in advance!!

update: working on solution looks (later script called in pre-commit hook)

tomato.sh

#!/bin/bash working_git_dir=$1 cd $working_git_dir # switch branch_to_merge branch_to_merge=$2 git checkout $branch_to_merge  parent_branch=$(git show-branch | grep '*' | grep -v "$(git rev-parse --abbrev-ref head)" | head -n1 | sed 's/.*\[\(.*\)\].*/\1/' | sed 's/[\^~].*//') echo $parent_branch # in memory merging of feature branch , parent , possible conflicts git merge-tree `git merge-base fetch_head $parent_branch` fetch_head $parent_branch 

how run

sh +x tomato.sh (path working_git_dir) (branch_to_merge) 

how script works

it tries find parent branch (look [here][2] detail). 3 way merge using :

git merge-tree <base> <branch1> <branch2> 

base -> find best-common-ancestor between current fetch_head & parent/nearest parent branch of current parent branch
branch1 -> current fetch_head
branch2 -> parent/nearest parent branch of current parent branch

this give in memory merge of remote , local branch without changing indexes.

please comment if improves script.

thanks in advance!

now want ensure not commit before pulling latest changes develop.

this isn't possible commits in git local

i think need team understanding work rebased on develop before pushing. enforce code review.

there may technological way enforce in ci.