A git tree object is very similar to a filesystem directory.
Filesystem directories refer to other directories and files, while git trees refer to other git trees and git blobs:
|Filesystem Directories Refer To:||Git Trees Refer To:|
|1. Other directories||1. Other git trees|
|2. Files||2. Git blobs (files)|
Example: Filesystem Directories and Files; Git Trees and Files
Diagram 1: The filesystem
In Diagram 1, below, an example filesystem directory and files is shown.
- There are 3 directories: src, docs and the top of the working directory.
- There are 4 files named README, hello.c, hello.py and hello. The contents of the files are shown in the grey boxes below the filenames.
Diagram 2: The Git Object Store
Diagram 2 shows how the files and directories are stored as git trees and blobs in the git object store, after the user adds and commits the files and directories to the git repository.
Diagram 2 shows the top of the git tree’s hash is 39179a1 (lower left-hand corner of the highest green triangle). That git tree refers to 3 objects:
- The blob that contains the contents of the README file.
- The tree that contains the contents of the src directory.
- The tree that contains the contents of the doc directory.
The first few bytes of the hash of each object is shown below the object.
Diagram 3: The Object Hashes
Diagram 3 adds annotation that shows how each object’s hash is referred to in the git trees.
Diagram 4: Objects Without Name Labels
Diagram 4 shows the same git object store, but without each of the objects including their name above the left side of the object. This more accurately that objects are stored by their hash. Git knows the name of an object when the object is referred to in a git tree: The git tree includes the object’s hash and its name.