MIT: Mini-Git implementation in Rust

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 MIT: Mini-Git implementation in Rust
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**[中文文档](./README.md)** | <u>English</u>

[Project Link](https://github.com/MrBeanCpp/MIT)

Git in Rust. A mini Git implementation called`mit`, implemented in `Rust`.

> Designed to be concise, readable, efficient, and secure.
>
> The best way to learn Git is to implement Git.
>
> This project aims to provide a `Git` implementation that even a second-grader can understand.
>
> `// rm -rf rigid design patterns & complex repository architecture`
>

**NOTE:** For a more comprehensive implementation of `Git`, please refer to another project of ours:
[Mega-Libra](https://github.com/web3infra-foundation/mega/tree/main/libra)

## Cross-Platform Support

-   [x] Windows
-   [x] MacOS
-   [x] Linux (Unix-like...)

## Key Features

- Supports input paths (pathspec): file paths, directory paths (absolute or relative, including `.`, `./`, `../`)

- Supports `mit init`, `mit add`, `mit rm`, `mit commit`

    -   [x] `init`: Initialize (does nothing if the repository already exists) - `idempotent`
    -   [x] `add`:  Add changes to the staging area (including new, modified, deleted), can specify files or directories
        - `-A(all)` : Stage all changes in the working directory (from the root) (new✅ modified✅ deleted✅)
        - `-u(update)`:  Operate only on tracked files in the staging area [`index`] (new❌ modified✅ deleted✅)
    -   [x] `rm`: Remove files from the staging area & working directory
        - `--cached` : Remove only from the staging area, untrack
        - `-r(recursive)`: Recursively delete directories, must specify this parameter when deleting directories
    -   [x] `commit`
    -   [x] `status`: Display the status of the working directory, staging area, and `HEAD` (only for the current
        directory); divided into three parts:
        - **Staged to be committed:**  Changes staged in the staging area compared to `HEAD` (last `Commit::Tree`),
          i.e., the last staging area
        - **Unstaged:** Changes in the working directory not staged in the staging area
        - **Untracked:** Files in the working directory not staged or tracked before
    -   [x] `log`

- Supports branches`mit branch`, `mit switch`, `mit restore`

    -   [x] `branch`
    -   [x] `switch`
        Unlike `checkout`, `switch` requires specifying `--detach` to switch to a `commit`, otherwise, it can only
        switch branches.
    -   [x] `restore`: Rollback files
        - Restore files at the specified path (including directories) to the version specified by `--source`, can
          specify staging area & working directory
            - `--source`： Can specify `Commit Hash`, `HEAD`, or `Branch Name`
        - If `--source` is not specified and neither `--staged` nor `--worktree` is specified, restore to the `HEAD`
          version, otherwise, restore from the staging area [`index`]
        - If neither `--staged` nor `--worktree` is specified, default to restore to `--worktree`
        - For files not present in `--source`, if tracked, delete; otherwise, ignore

- Supports simple merging `mit merge` (fast-forward)
    -   [x] Merge(FF)

## Notes

### ⚠️Testing requires single-threading

⚠️ Note: To avoid conflicts, please use `--test-threads=1` when executing tests.

For example:`cargo test -- --test-threads=1`

This is because testing involves IO on the same folder.

### Term Definitions

- Staging area: `index` or `stage`, stores file snapshots needed for the next `commit`
- Working directory: `worktree`, the folder directly manipulated by the user
- Repository: `working directory` or `repository`, the root directory of the code repository, where `.mit` is located
- `HEAD`：Points to the current`commit`
- Tracked：`tracked`，files already in the staging area [`index`](i.e., files that have been `add`-ed)

### Introductory Video

[【Mit】Rust implementation of Mini-Git - System Software Development Practice Final Report_Bilibili](https://www.bilibili.com/video/BV1p64y1E78W/)