How can I get git's `.git` path from git itself? - bash

I am trying to write a shell script that needs to be able to find the .git folder for the current directory, correctly handling all of the following possibilities:
I might be in a bare repo, in which case the .git folder is either . or .. or ../.. or so on.
I might be in a submodule (in which I'll find a .git file that contains the path to the git folder)
$GIT_DIR might be set.
I might not be in a git repo at all
I have this:
seemsToBeGitdir() {
# Nothing special about "config --local -l" here, it's just a git
# command that errors out if the `--git-dir` argument is wrong.
git --git-dir "$1" config --local -l >/dev/null 2>/dev/null
return $?
}
gitdir() {
local cursor relpath
if [ "$GIT_DIR" ]; then
echo "$GIT_DIR"
return 0
fi
cursor="$(pwd)"
while [ -e "$cursor" ] && ! seemsToBeGitdir "$cursor"; do
# Git won't traverse mountpoints looking for .git
if mountpoint -q "$cursor"; then
return 1
fi
# We might be in a submodule
if [ -f "$cursor/.git" ]; then
# If .git is a file, its syntax is "gitdir: " followed by a
# relative path.
relpath="$(awk '/^gitdir:/{print$2}' "$cursor/.git")"
# convert the relative path to an absolute path.
cursor="$(readlink -f "$cursor/$relpath")"
continue
fi
if seemsToBeGitdir "$cursor/.git"; then
echo "$cursor/.git"
return 0
fi
cursor="$(dirname "$cursor")"
done
echo "$cursor"
}
And it works, but seems way too complicated -- clearly, git itself does this sort of calculation every time it's invoked. Is there a way to make git itself tell me where .git is?

Use git rev-parse, which has options specifically for this:
git rev-parse --git-dir
See also:
git rev-parse --absolute-git-dir
(new in Git version 2.13.0), and:
git rev-parse --show-toplevel
and:
git rev-parse --show-cdup
(note that its output is empty if you are already in the top level of the repository). View your own documentation to find out which options your Git supports; most of these have been around since Git 1.7, though.

Related

bash, script to git add one file and commit

I'm trying to create a script to do this:
git add "file"
git commit -m "Comment"
My idea is to run:
gac "file" "Comment"
I know I can do something similar but for all files, with:
echo 'alias gac="/path/to/gitaddcommit.sh"' >> ~/.bash_profile
And the .sh would be:
!/bin/bash
git add .
echo “Enter commit message: “
git commit -am “$commitMessage”
Well you need two things :
A bin folder where you can put every sh script you want to use everywhere.
More knowledge about shell scripting and how you can get argv (in your ex: 'file' 'Comment')
So first go to your /home/<username> then mkdir bin && cd bin && pwd
then copy the pwd and add it into your PATH env variable inside your .bashrc
path example: PATH='/bin/:/sbin/:/home//bin
Then source ~/.bashrc you can now use every sh script inside you bin folder everywhere.
Cool so first problem done !
you don't have to do echo alias gac="/path/to/gitaddcommit.sh"' >> ~/.bash_profile anymore.
Now second problem here a post that can help you post
And let me show you for your example :
cd ~/bin && vi gac.sh
Now the script :
#!/bin/sh
if [ "$#" -ne 2 ]; then
echo "Usage: ./gac FILENAME COMMIT_MESSAGE" >&2
exit 1
fi
git add "$1"
git commit -am "$2"
First we check the number or arg then git add and commit.
Simple and fast maybe checking if arg one is a file might be a good idea too.
PS: i'm going to re write my post ahah
Here's what I have in my .bashrc:
ga ()
{
if test "$1" != "-f" && git rev-parse HEAD > /dev/null 2>&1 && ! git diff-index --quiet HEAD; then
echo 'Repo is dirty. -f to force' 1>&2;
return 1;
fi;
git add "$#";
list=$(git diff --name-only --cached | tr \\n \ );
git commit -m "Add $list"
}
The commit message is autogenerated, but you could easily modify it to prompt the user or take it from somewhere else.

Git-Bash File Lookup Depending On File Type

I am trying to navigate through all existing all branches and lookup if files with a certain extension such as (.zip or .exe exist)
I tried to write a bash script to achieve this task.
for branch in $(git branch);
do
echo "I am in: $branch"
git ls-files *.exe
done
I would like to see the file path when it is detected.
You are not changing to the branch so you are always checking the last branch you checked out. Try this:
# In the repo's working directory
for branch in $(git branch -a|grep -v remotes|sed 's/\*//g'); do
echo "I am in branch: ${branch}"
git checkout ${branch}
find . -type f -name '*.md'
done
Following is how I solved my problem:
read -p "Extension to lookup [example: .zip]: " extensionType
for branch in $(git branch);
do
if [[ $branch == *"Release"* ]]; then
echo "----------------------------------"
echo ">>Navigating to: $branch"
echo ">>$branch..."
git checkout $branch
git ls-files "*$extensionType"
echo "----------------------------------"
fi
done
I hope this helps.

change directory in bash is not affecting the post-commit hook

i've made the following bash script to commit the parent repo after some change in submodule.
it's all about that the script want to cd .. to check the parent repo current branch but the problem is that the cd .. is not affecting the upcoming commands because i guess the subshell
i've tried to run
1- cd ../ && before each command
2- make alias but didn't succeed
3- run exec but the script didn't continued
#!/bin/sh
#
# An example hook script to verify what is about to be committed.
# Called by "git commit" with no arguments. The hook should
# exit with non-zero status after issuing an appropriate message if
# it wants to stop the commit.
#
# To enable this hook, rename this file to "post-commit".
commit_msg= git log -1 --pretty=%B
if [[ $(git branch | grep \* | cut -d ' ' -f2) == "int1177/next" ]]; then
cd ..
if [[ $(git branch | grep \* | cut -d ' ' -f2) == "B0/next" ]]; then
git add 6_Tests
git commit -m "bs esss"
echo "development branch B0/next has now new commit"
else
echo "development branch isn't B0/next"
fi
else
echo "current branch isn't int1177/next"
fi
Actually, this particular problem is not a bash issue, but rather a Git issue.
Why doesn't "cd" work in a shell script? is valid in general, and is a suitable answer to many other questions. But this particular post-commit hook is trying to chdir out of a submodule into its parent superproject, then make a commit within the parent superproject. That is possible. It may be a bad idea for other reasons—in general it's unwise to have Git commit hooks create commits, even in other repositories1—but in this particular case you're running into the fact that Git finds its directories through environment variables.
In particular, there's an environment variable GIT_DIR that tells Git: The .git directory containing the repository is at this path. When Git runs a Git hook, Git typically sets $GIT_DIR to . or .git. If $GIT_DIR is not set, Git will find the .git directory by means of a directory-tree search, but if $GIT_DIR is set, Git assumes that $GIT_DIR is set correctly.
The solution is to unset GIT_DIR:
unset GIT_DIR
cd ..
The rest of the sub-shell commands will run in the one-step-up directory, and now that $GIT_DIR is no longer set, Git will search the superproject's work-tree for the .git directory for the superproject.
As an aside, this:
$(git branch | grep \* | cut -d ' ' -f2)
is a clumsy way to get the name of the current branch. Use:
git rev-parse --abbrev-ref HEAD
instead, here. (The other option is git symbolic-ref --short HEAD but that fails noisily with a detached HEAD, while you probably want the quiet result to be just the word HEAD, which the rev-parse method will produce.)
1The main danger in this case is that the superproject repository is not necessarily in any shape to handle a commit right now. Edit: or, as discovered in this comment, is not even set up to be a superproject for that submodule, yet, much less to have a submodule-updating commit added.

Automate post-"git move", making history log stick

I am facing merging of a few repositories in to one, with miscellaneous file moved around
Based on some research on SO, SO, how to merge repositories I ended up with following sketch:
user=some_user
new_superproj=new_proj # new repository, will include old repositories
hosting=bitbucket.org # gitgub etc
r1=repo1 # repo 1 to merge
r2=repo2
...
# clone to the new place. These are throw-away (!!!) directory
git clone git#${hosting}:${some_user}/${r1}.git
git clone git#${hosting}:${some_user}/${r2}.git
...
mkdir ${new_superproj} && cd ${new_superproj}
# dummy commit so we can merge
git init
dir > deleteme.txt
git add .
git commit -m "Initial dummy commit"
git rm ./deleteme.txt
git commit -m "Clean up initial file"
# repeat for all source repositories
repo=${r1}
pushd .
cd ../${repo}
# In the throw-away repository, move to the subfolder and rewrite log
git filter-branch --index-filter '
git ls-files -s |
sed "s,\t,&'"${repo}"'/," |
GIT_INDEX_FILE=$GIT_INDEX_FILE.new git update-index --index-info &&
mv $GIT_INDEX_FILE.new $GIT_INDEX_FILE
' HEAD
popd
# now bring data in to the new repository
git remote add -f ${repo} ../${repo}
git merge --allow-unrelated-histories ${repo}/master -m "Merging repo ${repo} in"
# remove remote to throw-away repo
git remote rm ${repo}
So far so good, unless we want to move files around while still preserving log. Git is sucks on move/rename and log rewrite fragment is not quite adapted, hence rewrite done uniform way, recursively for whole directory
Idea is, while files are moving we know there are no other changes in repository but renames and moves. So, how can I rewrite following part to be canonical, per file. Taken from git filter-branch, official documentation
git filter-branch --index-filter \
'git ls-files -s | sed "s-\t\"*-&newsubdir/-" |
GIT_INDEX_FILE=$GIT_INDEX_FILE.new \
git update-index --index-info &&
mv "$GIT_INDEX_FILE.new" "$GIT_INDEX_FILE"' HEAD
I have hard time to understand stuff past 'sed' and how it is applied for git filter-branch
I want to run script (bash, python etc), so:
for each file in repository get moved/renamed
...
# in the loop, moved/renamed file found
old_file="..." # e.g. a/b/c/old_name.txt
new_file="..." # e.g. a/b/f/g/new_name.txt, at this point it is known, old_file and new_file is the same file
update_log_paths(old_file, new_file) # <--- this part is needed
Any ideas?
As it turned out to be, hinting from the following command Move file-by-file in git, it is as simple as (pseudocode):
move_files
cd repo_root
git add . # so changes detected as moves, vs added/deleted
repo_moves=collect_moves_data()
git reset HEAD && git checkout . && git clean -df . # undo all moves
Biggest misunderstanding I found is "git log --follow" or other, "stronger" options doesn't work for many in related SO questions:
git log --follow <file>
does not show log until moved, while unchanged, file is committed.
for each_move in repo_moves
old_file, new_file=deduct_old_new_name(each_move)
new_dir=${new_file%/*}
filter="$filter \n\
if [ -e \"${old_file}\" ]; then \n\
echo \n\
if [ ! -e \"${new_dir}\" ]; then \n\
mkdir --parents \"${new_dir}\" && echo \n\
fi \n\
mv \"${old_file}\" \"${new_file}\" \n\
fi \n\
"
git filter-branch -f --index-filter "`echo -e $filter`"
If you need to get back:
git pull # with merge
git reset --hard <hash> # get hash of your origin/master, orignin/HEAD), which will be HEAD~2, but I'd check it manually and copy/paste hash

Ignore symbolic links in .gitignore

Is it possible to tell Git to ignore symlinks ? I'm working with a mixed Linux / Windows environment and, as you know, symlinks are handled very differently between the two.
Use git version >= 1.6
Git used to treat sym-links the same as regular files, but newer git versions (>= 1.6) check if a file is beyond a symbolic link and will throw a fatal error.
e.g.:
# git init
# mkdir newdir
# touch newdir/foo
# git add newdir/foo
# git commit -m 'add foo'
# mv newdir /tmp/
# ln -s /tmp/newdir
# touch newdir/bar
# git add newdir/bar
fatal: 'newdir/bar' is beyond a symbolic link
# git add/tmp/newdir
fatal: '/tmp/newdir' is outside repository
# git --version
git version 1.7.3.4
No, it is not possible to do this globally. However, if you have lots of symlinks here is a bash script that you can use to easily add them to your repo's .gitignore file:
for f in $(git status --porcelain | grep '^??' | sed 's/^?? //'); do
test -L "$f" && echo $f >> .gitignore; # add symlinks
test -d "$f" && echo $f\* >> .gitignore; # add new directories as well
done

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