worktree-clone.sh

#!/bin/bash

# Clone a repo as a bare repository optimized for a worktree-based workflow.
# Every branch becomes a sibling directory under one project folder.
#
# Usage: worktree-clone.sh <repo-url> [directory-name]

if ! command -v git >/dev/null 2>&1; then
    echo "Error: git is not installed"
    exit 1
fi

if [ $# -lt 1 ]; then
    echo "Usage: worktree-clone.sh <repo-url> [directory-name]"
    exit 1
fi

REPO_URL="$1"
DIR_NAME="${2:-$(basename "$REPO_URL" .git)}"

if [ -d "$DIR_NAME" ]; then
    echo "Error: Directory '$DIR_NAME' already exists"
    exit 1
fi

mkdir "$DIR_NAME" && cd "$DIR_NAME" || exit 1

git clone --bare "$REPO_URL" .bare
if [ $? -ne 0 ]; then
    echo "Failed to clone repository"
    cd ..
    rm -rf "$DIR_NAME"
    exit 1
fi

echo "gitdir: ./.bare" > .git

# Shared .envrc for all worktrees (direnv walks up directories)
cat > .envrc << 'ENVRC'
# Shared environment variables for all worktrees in this project.
# direnv automatically loads this from any worktree subdirectory.
# Add project-wide env vars below:

ENVRC
if command -v direnv >/dev/null 2>&1; then
    direnv allow .
fi

# Fix fetch refspec so `git fetch` grabs all remote branches
git config remote.origin.fetch "+refs/heads/*:refs/remotes/origin/*"

git fetch origin
if [ $? -ne 0 ]; then
    echo "Failed to fetch branches"
    exit 1
fi

# Determine the default branch
DEFAULT_BRANCH=$(git remote show origin | grep 'HEAD branch' | awk '{print $NF}')
if [ -z "$DEFAULT_BRANCH" ]; then
    DEFAULT_BRANCH="main"
fi

git worktree add "$DEFAULT_BRANCH"
if [ $? -eq 0 ]; then
    echo "Successfully cloned '$REPO_URL' into '$DIR_NAME/' with worktree '$DEFAULT_BRANCH/'"
else
    echo "Failed to create worktree for '$DEFAULT_BRANCH'"
    exit 1
fi