Content

TBA

Basics

clone repo:

$ git  clone  --recursive  REPO_ADDRESS

REPO_ADDRESS - url/path to git repo
--recursive - option to download submodules (nested git repos included in a repo)

duplicate repo with its full meta info:

$ git  clone  --bare  REPO_ADDRESS_SRC
$ cd  SRC
$ git  push  --mirror  REPO_ADDRESS_DST

REPO_ADDRESS_SRC - url/path to source git repo
REPO_ADDRESS_DST - url/path to destination git repo (must exist but without any commit nor branch)

update cloned repo:

$ git  pull

pull = fetch + merge

update meta info of remote repo origin:

$ git  fetch  ORIGIN

Branch

create empty branch without history:

$ git  checkout  --orphan  EMPTY_BRANCH
$ git  rm  -rf  .
$ rm  ...
$ git  commit  --allow-empty  -m "Init commit"
$ git  push  origin  EMPTY_BRANCH

create branch:

$ git  checkout  -b DST  SRC

DST - destination name for new local branch
SRC - commit/tag/branch from git repo

upload local branch to remote repo:

$ git  push  -u  origin  LOCAL_BRANCH

add upstream meta info (additional origin) into local forked repo:

$ git  remote  add  upstream  https://github.com/ORIGINAL_OWNER/ORIGINAL_REPOSITORY.git
$ git  fetch  upstream

Optionally (???):

$ git  merge  upstream/master  master

or:

$ git  rebase  upstream/master

make working directory out of branch:

$ git  worktree  add  PATH  BRANCH

merge branch:

$ git  checkout  DST
$ git  merge  SRC
$ git  push

DST - destination branch merge to
SRC - source branch merge from

rebase with fixed conflict:

if after non-conflicting changes/merges git shows something like:

On branch main
Your branch is up to date with 'upstream/main'.

You are currently rebasing branch 'BRANCH' on 'shaID'.
  (all conflicts fixed: run "git rebase --continue")

nothing to commit, working tree clean

then just do:

$ git  rebase  --abort

delete branch:

$ git  branch  -D BRANCH_TO_DELETE
$ git  push  origin  -d  BRANCH_TO_DELETE

Submodules

download submodules inside local cloned repo:

$ git  submodule  update  --init  [--recursive]

--recursive - option to download submodules (nested git repos included in a repo)

add a submodule inside local cloned repo:

$ git  submodule  add  -b BRANCH_TO_FETCH  REPO_ADDRESS
$ git  submodule  init

fix submodule update:

for the situation with a submodule like this one:

$ git  status

On branch main
Your branch is up to date with 'origin/main'.

Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git checkout -- <file>..." to discard changes in working directory)

	modified:   PATH/TO/LOCAL/SUBMODULE/IN/REPO (new commits)

no changes added to commit (use "git add" and/or "git commit -a")


$ git  diff

diff --git a/PATH/TO/LOCAL/SUBMODULE/IN/REPO b/PATH/TO/LOCAL/SUBMODULE/IN/REPO
index SHA_N..SHA_M X
--- a/PATH/TO/LOCAL/SUBMODULE/IN/REPO
+++ b/PATH/TO/LOCAL/SUBMODULE/IN/REPO
@@ -1 +1 @@
-Subproject commit SHA_OLD
+Subproject commit SHA_NEW

run:

$ git  submodule  update  --recursive  PATH/TO/LOCAL/SUBMODULE/IN/REPO

Management

full local state reset:

$ git  reset  --hard  &&  git  clean  -x -f -d

revert uncommitted changes in a particular local file:

$ git  checkout  --  FILE_NAME

revert commits:

revert changes from a particular commit only by creating additional commit in git history:

$ git  revert  SHA_ID

revert N commits (i.e., in case of 1 the latest commit only) by modifying commit history (rewind back git history by N commits basically):

$ git  reset  --hard HEAD~N

get a particular local file from a particular commit:

$ git  show  ID:path/to/file

where ID is SHA ID of a commit or a branch name.

get short SHA ID of the latest commit:

$ git  rev-parse  --short  HEAD

get tag by SHA ID commit:

$ git  tag  --points-at SHA_ID

get branch name:

$ git  symbolic-ref  --short  HEAD

get detached status

$ git TBA

get list of commits inside branch:

$ git  log  --oneline  main..branch

get list of files changed during commits inside branch:

$ git  log  --oneline  main..branch  --names-only

Configuration

set end-of-line type

add to core section of ~/.gitconfig file:

[core]
	autocrlf = input
	TBA

editor

using shell command:

$ git  config  --global  core.editor  COMMAND

add to core section of ~/.gitconfig file:

[core]
	editor = COMMAND

diff tool

using shell commands:

$ git  config  --global  diff.tool   COMMAND
$ git  config  --global  merge.tool  COMMAND
$ git  config  --global  --add  difftool.prompt  false

using config: add to diff section of ~/.gitconfig file:

[diff]
	tool = COMMAND

ignore files (global setting):

add to core section of ~/.gitconfig file:

[core]
	...
	excludesfile = ~/.gitignore

add list of must-to-be-ignored files in ~/.gitignore file:

GPATH
GRTAGS
GTAGS
tags
cscope.in.out
cscope.out
cscope.po.out

GNU/Linux key ring integration

add to credential section of ~/.gitconfig file:

[credential]
	helper = libsecret

Github

Wiki update

uncommitted changes in a particular local file:

create wiki for your cloned project
clone wiki from forked repo and add remote for upstream:

git clone git@ssh.gihub.com:YOUR_USERNAME/FORKED_REPO.wiki.git
git remote add upstream https://github.com/ORIGINAL_USERNAME/ORIG_REPO.wiki.git

fetch upstream git meta info:

git fetch upstream

create branch with wiki from upstream:

git checkout -b upstream upstream/master

switch back to your branch of forked wiki:

git checkout master

merge changes from upstream wiki branch to your forked wiki branch:

git merge upstream
git commit -m "Merge from upstream to forked wiki"

Git meta info for GitHub Actions

If .github/workflows/push.yml is being used for CI/CD purposes, then during checkout on GitHub infrastructure a git repo will be in detached state. To deal with this, add sub-sections like these into steps section:

      - ...

      - uses: actions/checkout@v4
        with:
          submodules: true
          fetch-tags: true
          fetch-depth: 0

      - name: Set git meta info
        run: echo "GITHUB_CI_PR_SHA=${{github.event.pull_request.head.sha}}" >> "${GITHUB_ENV}"

      - ...

So after that, submodules, tags & full commit history will be available during build/test/etc, and shell environment variable "${GITHUB_CI_PR_SHA}" will be holding the full actual latest SHA ID commit.

Files

faq_git.md

Latest commit

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