README.md

   1 git-cheat-sheet
   2 ===============
   3
   4 How to do stuff with git
   5
   6
   7 Splitting a repo
   8 ----------------
   9
  10 ##### Remove history of all but select files in cloned repo
  11 ```sh
  12 $ git clone old new
  13 $ cd new
  14 $ git clean -dfx
  15 $ git gc --aggressive --prune=now
  16 $ git remote rm origin
  17 $ git filter-branch \
  18     --prune-empty \
  19     --index-filter '
  20         git ls-tree -r --name-only HEAD \
  21         | grep -v file_i_want_to_keep_1 \
  22         | grep -v file_i_want_to_keep_.. \
  23         | grep -v file_i_want_to_keep_n \
  24         | xargs git rm --cached -r --ignore-unmatch
  25     ' \
  26     HEAD
  27 $ git gc --aggressive --prune=now
  28 ```
  29
  30 ##### Remove history of previously-removed (not in current tree) files
  31 ```sh
  32 $ git log --pretty=format: --name-status \
  33     | awk '$0 != "" {print $2}' \
  34     | sort -u > /tmp/tree.old
  35 $ git ls-tree -r --name-only HEAD > /tmp/tree.new
  36 $ git filter-branch \
  37     --prune-empty \
  38     --index-filter '
  39         grep -Fvxf /tmp/tree.new /tmp/tree.old \
  40         | xargs git rm --cached -r --ignore-unmatch
  41     ' \
  42     HEAD
  43 ```
  44
  45
  46 Inserting a new root commit
  47 ---------------------------
  48 ```sh
  49 git checkout --orphan $TEMP_BRANCH
  50 git rm -rf .
  51 git commit --allow-empty -m $INIT_COMMIT_MSG
  52 git rebase --onto $TEMP_BRANCH --root $MAIN_BRANCH
  53 git branch -d $TEMP_BRANCH
  54 ```
  55
  56
  57 Deleting all tags, locally and remotely
  58 ---------------------------------------
  59 ```sh
  60 for tag in `git tag`;
  61 do
  62     git tag -d $tag
  63     git push $REMOTE_NAME :refs/tags/$tag
  64 done
  65 ```
  66
  67
  68 Get an older version of a file
  69 ------------------------------
  70
  71 ```sh
  72 git cat-file -p $COMMIT_DIGEST:$FILE_PATH
  73 ```
  74
  75
  76 Splitting a commit
  77 ------------------
  78
  79 From [docs](https://git-scm.com/docs/git-rebase#_splitting_commits):
  80
  81 - Start an interactive rebase with `git rebase -i <commit>^`, where `<commit>`
  82   is the commit you want to split.
  83 - Mark the commit you want to split with the action "edit".
  84 - When it comes to editing that commit, execute `git reset HEAD^`. The effect
  85   is that the HEAD is rewound by one, and the index follows suit. However, the
  86   working tree stays the same.
  87 - Now add the changes to the index that you want to have in the first commit
  88   (`git add`)
  89 - Commit the now-current index with whatever commit message is appropriate now.
  90 - Repeat the last two steps until your working tree is clean.
  91 - Continue the rebase with `git rebase --continue`.