diff --git a/src/git/git.rs b/src/git/git.rs
index 528ba19..1f572bd 100644
--- a/src/git/git.rs
+++ b/src/git/git.rs
@@ -348,3 +348,463 @@ impl Git {
         Ok(content)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use git2::Oid;
+    use serde::Serialize;
+    use std::{
+        io::Write,
+        process::{Command, Stdio},
+    };
+    use tempfile::TempDir;
+
+    use super::Git;
+
+    macro_rules! execute_commands {
+        ($($cmd:expr $(, $arg:expr)*)* ) => {
+            {
+                $(
+                    let cmd_string = format!("{} {}", $cmd, vec![$($arg),*].join(" "));
+                    println!("{}", cmd_string);
+                    let child = Command::new($cmd)
+                        $(.arg($arg))*
+                        .stdout(Stdio::piped())
+                        .spawn()
+                        .expect("Failed to spawn child process");
+
+                    let output = child.wait_with_output().expect("Failed to read stdout");
+                    if !output.status.success() {
+                        panic!("the command did not succeed");
+                    }
+                    String::from_utf8(output.stdout).expect("should be parasable")
+                )*
+            }
+        };
+    }
+
+    struct GitTmp {
+        bare: Option<TempDir>,
+        directory: TempDir,
+    }
+
+    impl Clone for GitTmp {
+        fn clone(&self) -> Self {
+            let clone = TempDir::new().expect("directory should be created");
+            let Some(ref bare) = self.bare else {
+                todo!("no bare repository: impossible to clone")
+            };
+
+            execute_commands!(
+                "git",
+                "clone",
+                &format!("file://{}", bare.path().to_str().unwrap().to_string()),
+                &clone.path().to_str().unwrap().to_string()
+            );
+
+            Self {
+                bare: None,
+                directory: clone,
+            }
+        }
+    }
+
+    /// Helper that execute git command
+    ///
+    /// So that git.rs can be tested against the git binary
+    impl GitTmp {
+        /// Create a repository with a bare one
+        fn init_bare(initial_branch: &str) -> Self {
+            let bare = tempfile::Builder::new()
+                .suffix(".git")
+                .tempdir()
+                .expect("git bare folder to be created");
+
+            execute_commands!(
+                "git",
+                "-C",
+                &bare.path().to_str().unwrap().to_string(),
+                "init",
+                "--initial-branch",
+                initial_branch,
+                "--bare"
+            );
+
+            // Then we clone it
+            let clone = TempDir::new().expect("Directory should be created");
+
+            execute_commands!(
+                "git",
+                "clone",
+                &format!("file://{}", bare.path().to_str().unwrap().to_string()),
+                &clone.path().to_str().unwrap().to_string()
+            );
+
+            Self {
+                bare: Some(bare),
+                directory: clone,
+            }
+        }
+
+        /// Add a file to the repository
+        fn new_file(&self, file_name: &str, content: &str) {
+            let path = self.directory.path().join(file_name);
+            let mut file = std::fs::File::create(path).expect("file should be created");
+            file.write_all(content.as_bytes())
+                .expect("should have written file to disk");
+        }
+
+        /// Add all files to the next commit
+        fn add_all(&self) {
+            let _ = execute_commands!("git", "-C", &self.path(), "add", ".");
+        }
+
+        /// Commit the change
+        fn commit(&self, commit_name: &str) -> Oid {
+            let _ = execute_commands!("git", "-C", &self.path(), "commit", "-m", commit_name);
+            let oid = execute_commands!("git", "-C", &self.path(), "rev-parse", "HEAD");
+            let oid = oid.trim();
+
+            Oid::from_str(&oid).unwrap()
+        }
+
+        fn add_note<N>(&self, oid: Oid, note: &N)
+        where
+            N: Serialize,
+        {
+            let json = serde_json::to_string(note).expect("note");
+            execute_commands!(
+                "git",
+                "-C",
+                &self.path(),
+                "notes",
+                "add",
+                "-m",
+                &json,
+                &oid.to_string()
+            );
+        }
+
+        fn push(&self) {
+            execute_commands!("git", "-C", &self.path(), "push", "--force");
+        }
+
+        /// Returns the path of the repository
+        fn path(&self) -> String {
+            self.directory.path().to_str().unwrap().to_string()
+        }
+
+        /// Modifies the title of HEAD
+        fn amend(&self, title: &str) {
+            execute_commands!("git", "-C", &self.path(), "commit", "--amend", "-m", title);
+        }
+
+        /// pull the repository
+        fn pull(&self) {
+            execute_commands!("git", "-C", &self.path(), "pull");
+        }
+
+        fn create_branch(&self, branch_name: &str) {
+            execute_commands!("git", "-C", &self.path(), "checkout", "-b", branch_name);
+        }
+    }
+
+    #[test]
+    fn test_open_repository() {
+        let repo = GitTmp::init_bare("main");
+        let _ = Git::open(&repo.path()).expect("repo should exist");
+    }
+
+    #[test]
+    fn test_open_repository_not_found() {
+        let tmp = TempDir::new().expect("the folder should be created");
+        let result = Git::open(tmp.path().to_str().unwrap());
+        assert!(result.is_err())
+    }
+
+    #[test]
+    fn test_open_relative_repository() {
+        let _ = Git::open(".");
+    }
+
+    /// helper that initialize a repository with one commit
+    ///
+    /// It returns the head and the repository
+    fn init_repo_with_commit() -> (Oid, GitTmp) {
+        let repo = GitTmp::init_bare("main");
+        repo.new_file(
+            "readme.md",
+            concat!("# Star wars", "\n", "Hello there\n", "General Kenobi\n"),
+        );
+        repo.add_all();
+        let oid = repo.commit("first commit");
+        repo.add_note(oid, &"my super note".to_string());
+        (oid, repo)
+    }
+
+    #[test]
+    fn test_find_commit() {
+        let (head, repo) = init_repo_with_commit();
+        let git = Git::open(&repo.path()).expect("should be able to open the repository");
+        let commit = git
+            .find_commit::<String>(head)
+            .expect("commit should be present");
+        assert_eq!(commit.title, "first commit");
+    }
+
+    #[test]
+    fn test_commit_not_found() {
+        let (_, repo) = init_repo_with_commit();
+        let git = Git::open(&repo.path()).expect("should be able to open the repository");
+        let commit = git.find_commit::<String>(Oid::zero());
+        assert!(commit.is_none())
+    }
+
+    #[test]
+    fn test_get_note() {
+        let (head, repo) = init_repo_with_commit();
+        let git = Git::open(&repo.path()).expect("should be able to open the repository");
+        let note = git
+            .find_note::<String>(head)
+            .expect("the note has to be present");
+        assert_eq!(note, "my super note");
+    }
+
+    #[test]
+    fn test_get_no_note() {
+        let (_, repo) = init_repo_with_commit();
+        let git = Git::open(&repo.path()).expect("should be able to open the repository");
+        let note = git.find_note::<String>(Oid::zero());
+        assert!(note.is_none());
+    }
+
+    #[test]
+    fn test_delete_note() {
+        let (head, repo) = init_repo_with_commit();
+        let git = Git::open(&repo.path()).expect("should be able to open the repository");
+        let note = git
+            .find_note::<String>(head)
+            .expect("the note has to be present");
+        assert_eq!(note, "my super note");
+        git.delete_note(&head).expect("not should be deleted");
+        let note = git.find_note::<String>(head);
+        assert!(note.is_none())
+    }
+
+    #[test]
+    fn test_set_note() {
+        let (head, repo) = init_repo_with_commit();
+        let git = Git::open(&repo.path()).expect("should be able to open the repository");
+        git.set_note(head, "a note").expect("not should be written");
+        let note = git
+            .find_note::<String>(head)
+            .expect("the note has to be present");
+        assert_eq!(note, "a note");
+    }
+
+    #[test]
+    fn test_overwrite_note() {
+        let (head, repo) = init_repo_with_commit();
+
+        let git = Git::open(&repo.path()).expect("should be able to open the repository");
+        git.set_note(head, "a note").expect("not should be written");
+        git.set_note(head, "a note 2")
+            .expect("not should be written");
+
+        let note = git
+            .find_note::<String>(head)
+            .expect("the note has to be present");
+
+        assert_eq!(note, "a note 2");
+    }
+
+    #[test]
+    fn test_delete_note_two_times() {
+        let (head, repo) = init_repo_with_commit();
+
+        let git = Git::open(&repo.path()).expect("should be able to open the repository");
+
+        git.delete_note(&head).expect("should work");
+        git.delete_note(&head).expect("should work");
+    }
+
+    #[test]
+    fn test_push_force_with_lease_refused() {
+        let repo = GitTmp::init_bare("main");
+        let clone = repo.clone();
+
+        repo.new_file(
+            "readme.md",
+            concat!("# Star wars", "\n", "Hello there\n", "General Kenobi\n"),
+        );
+        repo.add_all();
+        repo.commit("first commit");
+        repo.new_file(
+            "other_file.md",
+            concat!(
+                "# Pride and prejudice",
+                "\n",
+                "I love you. Most ardently.\n"
+            ),
+        );
+        repo.add_all();
+        repo.commit("pride and prejudice");
+
+        // Let's open git in clone
+        let git = Git::open(&clone.path()).expect("git should be open");
+        // let's add a file and commit it
+        clone.new_file("yolo.md", "some content");
+        clone.add_all();
+        clone.commit("my first commit");
+        clone.push(); // To create a local remote
+
+        // let's push force from repo
+        // it will delete the history of clone
+        repo.push();
+        // the push force with lease should be refused because the origin has divered
+        let result = git.push_force_with_lease("origin", "main");
+        assert!(result.is_err());
+    }
+
+    #[test]
+    fn test_push_force_with_lease_accepted() {
+        let repo = GitTmp::init_bare("main");
+        let clone = repo.clone();
+
+        repo.new_file(
+            "readme.md",
+            concat!("# Star wars", "\n", "Hello there\n", "General Kenobi\n"),
+        );
+        repo.add_all();
+        repo.commit("first commit");
+        repo.new_file(
+            "other_file.md",
+            concat!(
+                "# Pride and prejudice",
+                "\n",
+                "I love you. Most ardently.\n"
+            ),
+        );
+        repo.add_all();
+        repo.commit("pride and prejudice");
+        repo.push();
+
+        // Let's open git in clone
+        let git = Git::open(&clone.path()).expect("git should be open");
+        // let's add a file and commit it
+        clone.pull();
+        clone.amend("hello again"); // The history has been modified
+        clone.new_file("anotherfile.md", "hello other file");
+        clone.add_all();
+        clone.commit("new commit");
+        // the two origins matched, so we can erase the history
+        let result = git.push_force_with_lease("origin", "main");
+        assert!(result.is_ok());
+    }
+
+    #[test]
+    fn test_push_force() {
+        let repo = GitTmp::init_bare("main");
+        let clone = repo.clone();
+
+        repo.new_file(
+            "readme.md",
+            concat!("# Star wars", "\n", "Hello there\n", "General Kenobi\n"),
+        );
+        repo.add_all();
+        repo.commit("first commit");
+        repo.new_file(
+            "other_file.md",
+            concat!(
+                "# Pride and prejudice",
+                "\n",
+                "I love you. Most ardently.\n"
+            ),
+        );
+        repo.add_all();
+        repo.commit("pride and prejudice");
+
+        // Let's open git in clone
+        let git = Git::open(&clone.path()).expect("git should be open");
+        // let's add a file and commit it
+        clone.new_file("yolo.md", "some content");
+        clone.add_all();
+        clone.commit("my first commit");
+        clone.push(); // To create a local remote
+
+        // let's push force from repo
+        // it will delete the history of clone
+        repo.push();
+        // This test is based on the push_force_with_lease one
+        // where push --force-with-lease fails, push --force has to work
+        let result = git.push_force("origin", "main");
+        assert!(result.is_ok());
+    }
+
+    // Testing `main_branch`
+
+    /// Initializes a repository with a main branch
+    fn init_main_branch_test(initial_branch: &str) -> GitTmp {
+        let repo = GitTmp::init_bare(initial_branch);
+        repo.new_file(
+            "readme.md",
+            concat!("# Star wars", "\n", "Hello there\n", "General Kenobi\n"),
+        );
+        repo.add_all();
+        repo.commit("first commit");
+        repo.push();
+        repo
+    }
+
+    #[test]
+    fn test_find_main_branch_main() {
+        let repo = init_main_branch_test("main");
+        let git = Git::open(&repo.path()).unwrap();
+        let branch = git.main_branch().unwrap();
+        let branch = branch.name().unwrap().unwrap();
+        assert_eq!(branch, "main");
+    }
+
+    #[test]
+    fn test_find_main_branch_master() {
+        let repo = init_main_branch_test("master");
+        let git = Git::open(&repo.path()).unwrap();
+        let branch = git.main_branch().unwrap();
+        let branch = branch.name().unwrap().unwrap();
+        assert_eq!(branch, "master");
+    }
+
+    #[test]
+    fn test_find_unknown_branch() {
+        let repo = init_main_branch_test("unknown");
+        let git = Git::open(&repo.path()).unwrap();
+        let branch = git.main_branch();
+        assert!(branch.is_none())
+    }
+
+    #[test]
+    fn test_list_commits_from_main() {
+        let (_, repo) = init_repo_with_commit();
+        let git = Git::open(&repo.path()).unwrap();
+        let commits = git.list_commits::<String>().unwrap();
+        assert_eq!(commits.len(), 0) // because we are on main
+    }
+
+    #[test]
+    fn test_list_commits_from_other_branch() {
+        let (_, repo) = init_repo_with_commit();
+        repo.create_branch("test");
+        repo.new_file("hey", "hey");
+        repo.add_all();
+        let oid = repo.commit("first commit on my branch");
+
+        let git = Git::open(&repo.path()).unwrap();
+        let commits = git.list_commits::<String>().unwrap();
+        assert_eq!(commits.len(), 1);
+        let commit = commits.iter().next().unwrap();
+        assert_eq!(commit.id, oid);
+        assert_eq!(commit.note, None);
+        assert_eq!(commit.title, "first commit on my branch");
+        assert_eq!(commit.description, Some("".to_string())); // TODO: empty string should not be allowed
+    }
+}