Git compare tool

Simple command-line tool for fast comparison between two branches

NB: The same functionality is provided out-of-the-box by git-diff tool

How it's useful

• you performed rebase with commit fixups/reordering/conflict resolutions
  and want to make sure new version didn't introduce any unintended code lines or dropped useful ones
• you want to see the differences between the current branch (HEAD) and other branch (git cmp other_branch)
• you want to see the differences between any two branches (git cmp branch1 branch2)

Usage Example

1. Suppose you started with the following repository state:
   
2. Now suppose you want to switch order for second and third commits and edit the contents of the first commit.
   You do that with the following git command: git rebase -i HEAD~3
   The repository reflects the changes:
   
3. To see all the differences between master and masterBackup branches
   you can execute the following git command: git cmp master masterBackup (or shorter: git cmp masterBackup)
   Now there's two possible outputs:
   a) You didn't introduce any changes:
   
   b) You did introduce some changes (which may be intended or not):
   
4. Now you know exactly what changed after rebase.
   It's up to you to decide what to do next (delete masterBackup branch or discard rebase, for example)

Getting Started

Prerequisites

Installed git

Setup (with Windows examples)

1. Download and save cmp.sh in a folder of your preference (for example: "C:/scripts")
2. Add alias to global .gitconfig file (default path: "C:/users/%username%/.gitconfig"):
   git config --global alias.cmp '!sh C:/scripts/cmp.sh'
3. Check whether it works by typing in bash shell: git cmp
   The output should look something like this:

$ git cmp
Illegal number of arguments (1-2 expected, 0 provided)
usage: C:/scripts/cmp.sh [local_committish] remote_committish
  local_committish      current tree state. HEAD by default
  remote_committish     previous tree state
  note: "committish" is a commit hash/branch name/tag

4. You are awesome! From now on you have a tool relieving you from anxiety after any non-trivial rebase

Platforms

Windows & Unix

Authors

• Andronov Alexey - Idea & Implementation - git-cmp