An independant implementation of a mini version of Git

more in test.md

• blobs: The saved contents of files. Since Gitlet saves many versions of files, a single file might correspond to multiple blobs: each being tracked in a different commit.

• trees: Directory structures mapping names to references to blobs and other trees (subdirectories).

• commits: Combinations of log messages, other metadata (commit date, author, etc.), a reference to a tree, and references to parent commits. The repository also maintains a mapping from branch heads to references to commits, so that certain important commits have symbolic names.

• Incorporating trees into commits and not dealing with subdirectories (so there will be one “flat” directory of plain files for each repository).

• Limiting ourselves to merges that reference two parents (in real Git, there can be any number of parents.)

• Having our metadata consist only of a timestamp and log message. A commit, therefore, will consist of a log message, timestamp, a mapping of file names to blob references, a parent reference, and (for merges) a second parent reference.

Usage: java gitlet.Main init

Creates a new Gitlet version-control system in the current directory

Usage: java gitlet.Main add [file name]

Adds a copy of the file as it currently exists to the staging area

Differences from real git: In real git, multiple files may be added at once. In gitlet, only one file may be added at a time.

Usage: java gitlet.Main commit [message]

Saves a snapshot of tracked files in the current commit and staging area so they can be restored at a later time, creating a new commit.

Differences from real git: In real git, commits may have multiple parents (due to merging) and also have considerably more metadata.

Usage: java gitlet.Main rm [file name]

Usage: java gitlet.Main log

Starting at the current head commit, display information about each commit backwards along the commit tree until the initial commit, following the first parent commit links, ignoring any second parents found in merge commits.

Usage: java gitlet.Main global-log

Like log, except displays information about all commits ever made.

Usage: java gitlet.Main find [commit message]

Prints out the ids of all commits that have the given commit message, one per line.

Differences from real git: Doesn’t exist in real git. Similar effects can be achieved by grepping the output of log.

Usage: java gitlet.Main status

Displays what branches currently exist, and marks the current branch with a *. Also displays what files have been staged for addition or removal.

Usages:

1. java gitlet.Main checkout -- [file name]
2. java gitlet.Main checkout [commit id] -- [file name]
3. java gitlet.Main checkout [branch name]

Differences from real git: Real git does not clear the staging area and stages the file that is checked out. Also, it won’t do a checkout that would overwrite or undo changes (additions or removals) that you have staged.

Usage: java gitlet.Main branch [branch name]

Creates a new branch with the given name, and points it at the current head commit.

Usage: java gitlet.Main reset [commit id]

Differences from real git: This command is closest to using the --hard option, as in git reset --hard [commit hash].

Usage: java gitlet.Main merge [branch name]

Differences from real git: Real Git does a more subtle job of merging files, displaying conflicts only in places where both files have changed since the split point. Real Git has a different way to decide which of multiple possible split points to use. Real Git will force the user to resolve the merge conflicts before committing to complete the merge. Gitlet just commits the merge, conflicts and all, so that you must use a separate commit to resolve problems. Real Git will complain if there are unstaged changes to a file that would be changed by a merge. You may do so as well if you want, but we will not test that case.

Usage: java gitlet.Main add-remote [remote name] [name of remote directory]/.gitlet

Saves the given login information under the given remote name.

Usage: java gitlet.Main rm-remote [remote name]

Remove information associated with the given remote name.

Usage: java gitlet.Main push [remote name] [remote branch name]

Attempts to append the current branch’s commits to the end of the given branch at the given remote.

Usage: java gitlet.Main fetch [remote name] [remote branch name]

Brings down commits from the remote Gitlet repository into the local Gitlet repository.

Usage: java gitlet.Main pull [remote name] [remote branch name]

Fetches branch [remote name]/[remote branch name] as for the fetch command, and then merges that fetch into the current branch. Fetches branch [remote name]/[remote branch name] as for the fetch command, and then merges that fetch into the current branch.