Git is a Command Line Interfacetool for version control of source code for software.
Data model
Git models the history of a collection of files and folders within some top-level directory as a series of snapshots. In Git terminology, a file is called a “blob”, and it’s just a bunch of bytes. A directory is called a “tree”, and it maps names to blobs or trees (so directories can contain other directories). A snapshot is the top-level tree that is being tracked. For example, we might have a tree as follows:
<root> (tree)
|
+- foo (tree)
| |
| + bar.txt (blob, contents = "hello world")
|
+- baz.txt (blob, contents = "git is wonderful")
The top-level tree contains two elements, a tree “foo” (that itself contains one element, a blob “bar.txt”), and a blob “baz.txt”.
Initialise Git Project
git init
Add Files
git add .
Show files in a commit
git show —pretty=“” —name-only <commit-id>
Branching
Checkout an existing branch
git checkout <branch-name>
Create a branch
git branch <branch-name>
Merge a branch
git checkout <branch-name> # Checkout branch to merge “to”
git merge <branch-name> # Choose branch to merge back
Delete a branch
git branch -d <branch-name>
Diff
Show changes to unstaged files
git diff
Show changes to staged files
git diff —cached
Show changes to staged and unstaged files
git diff HEAD
Show diff between two commits
git diff <commit-id-1> <commit-id-2>
Log
Show log of commits
git log
Search log of commits
# Tell grep to also include 5 lines up, so we get commit id
git log | grep “<my search term>” -B 5