From 972319c1811e1a9c4f491a03ba92ea5a624cca5e Mon Sep 17 00:00:00 2001
From: Justin Wernick <justin@worthe-it.co.za>
Date: Mon, 10 Apr 2023 21:31:02 +0200
Subject: Update the main branch of a repo

---
 readme.org    |  2 +-
 src/git.rs    | 25 ++++++++++++++++++++++++-
 src/lib.rs    |  7 ++++++-
 src/parser.rs |  9 +++++++++
 4 files changed, 40 insertions(+), 3 deletions(-)

diff --git a/readme.org b/readme.org
index 9dc3eb8..a63a3d9 100644
--- a/readme.org
+++ b/readme.org
@@ -41,7 +41,7 @@ Pijul.
   - [X] change an existing repo
 - [X] Change ~git-init~ name to just be ~init~. Later, the ~git~ part will be an
   option which defaults to git.
-- [ ] set the main branch of a repo
+- [X] set the main branch of a repo
 - [ ] help docs on all the commands
 
 ** Post-MVP
diff --git a/src/git.rs b/src/git.rs
index 4b1ec0d..1159e7f 100644
--- a/src/git.rs
+++ b/src/git.rs
@@ -69,9 +69,14 @@ pub fn init(
     repo_name: &str,
     group: &Option<String>,
     description: &Option<String>,
+    branch: &str,
 ) -> Result<GitInitResult, ShackleError> {
     let mut init_opts = RepositoryInitOptions::new();
-    init_opts.bare(true).mkdir(true).no_reinit(true);
+    init_opts
+        .bare(true)
+        .mkdir(true)
+        .no_reinit(true)
+        .initial_head(branch);
 
     let path = match group {
         Some(group) => {
@@ -167,6 +172,24 @@ pub fn set_description(directory: &PathBuf, description: &str) -> Result<(), Sha
     }
 }
 
+pub fn set_branch(directory: &PathBuf, branch: &str) -> Result<(), ShackleError> {
+    if !is_valid_git_repo_path(&directory)? {
+        return Err(ShackleError::InvalidDirectory);
+    }
+
+    if let Ok(repo) = Repository::open_bare(&directory) {
+        repo.reference_symbolic(
+            "HEAD",
+            &format!("refs/heads/{branch}"),
+            true,
+            "shackle set-branch",
+        )?;
+        Ok(())
+    } else {
+        Err(ShackleError::InvalidDirectory)
+    }
+}
+
 pub fn upload_pack(upload_pack_args: &GitUploadPackArgs) -> Result<(), ShackleError> {
     if !is_valid_git_repo_path(&upload_pack_args.directory)? {
         return Err(ShackleError::InvalidDirectory);
diff --git a/src/lib.rs b/src/lib.rs
index 196078c..134ba97 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -33,12 +33,17 @@ pub fn run_command(user_input: String) -> Result<ControlFlow<(), ()>, ShackleErr
             git::set_description(&directory, &description)?;
             println!("Successfully updated description");
         }
+        Ok(ShackleCommand::SetBranch(SetBranchArgs { directory, branch })) => {
+            git::set_branch(&directory, &branch)?;
+            println!("Successfully updated branch");
+        }
         Ok(ShackleCommand::Init(InitArgs {
             repo_name,
             group,
             description,
+            branch,
         })) => {
-            let init_result = git::init(&repo_name, &group, &description)?;
+            let init_result = git::init(&repo_name, &group, &description, &branch)?;
             println!("Successfully created \"{}\"", init_result.path.display());
         }
         Ok(ShackleCommand::GitUploadPack(upload_pack_args)) => {
diff --git a/src/parser.rs b/src/parser.rs
index 14b1a49..3a7d129 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -14,6 +14,7 @@ pub enum ShackleCommand {
     /// List all repositories available
     List,
     SetDescription(SetDescriptionArgs),
+    SetBranch(SetBranchArgs),
     Init(InitArgs),
     GitUploadPack(GitUploadPackArgs),
     GitReceivePack(GitReceivePackArgs),
@@ -25,12 +26,20 @@ pub struct SetDescriptionArgs {
     pub description: String,
 }
 
+#[derive(Parser, Clone, Debug, PartialEq, Eq)]
+pub struct SetBranchArgs {
+    pub directory: PathBuf,
+    pub branch: String,
+}
+
 #[derive(Parser, Clone, Debug, PartialEq, Eq)]
 pub struct InitArgs {
     #[arg(long)]
     pub group: Option<String>,
     #[arg(long)]
     pub description: Option<String>,
+    #[arg(long, default_value = "main")]
+    pub branch: String,
     pub repo_name: String,
 }
 
-- 
cgit v1.2.3