From d6f497cdf03b253fd3231d4e95857f7d59cc2a99 Mon Sep 17 00:00:00 2001
From: Tega McKinney <tega@hey.com>
Date: Wed, 24 Sep 2025 22:06:56 -0400
Subject: [PATCH] feat(wtadd): add branch-name and commit-ish flags to allow
 more control

---
 wtadd.sh | 110 +++++++++++++++++++++++++++++++++++--------------------
 1 file changed, 71 insertions(+), 39 deletions(-)

diff --git a/wtadd.sh b/wtadd.sh
index e4cd9c8..a3c8b7b 100755
--- a/wtadd.sh
+++ b/wtadd.sh
@@ -8,21 +8,30 @@ GREEN="\033[0;32m"
 YELLOW="\033[0;33m"
 CLEAR="\033[0m"
 VERBOSE=
-
-echo $1
+BRANCH_NAME=
+COMMIT_ISH=
 
 function usage {
     cat <<EOF
-Usage: wtadd [-vh] WORKTREE_NAME [BRANCH_NAME]
-Create a git worktree named WORKTREE_NAME based on BRANCH_NAME.
-If no BRANCH_NAME is provided, it will default to the current branch.
+Usage: wtadd [-vh] [-b BRANCH_NAME] [-c COMMIT-ISH] WORKTREE_NAME
+Create a git worktree named WORKTREE_NAME.
 
-Will copy over any .env, .envrc, .tool-versions, or mise.toml files to the 
+Will copy over any .env, .envrc, .tool-versions, or mise.toml files to the
 new worktree as well as node_modules.
 
 FLAGS:
-  -h, --help    Print this help
-  -v, --verbose Verbose mode   
+  -h, --help               Print this help
+  -v, --verbose            Verbose mode
+  -b, --branch BRANCH_NAME Specify branch name for the new worktree
+                          (defaults to WORKTREE_NAME if not provided)
+  -c, --commit COMMIT-ISH  Create worktree from specific commit, tag, or branch
+                          (can be SHA, tag name, or branch reference)
+
+EXAMPLES:
+  wtadd feature-work                    # Creates worktree and branch both named "feature-work"
+  wtadd -b my-feature feature-work      # Creates worktree "feature-work" with branch "my-feature"
+  wtadd -c main experiment              # Creates worktree "experiment" from main branch
+  wtadd -b hotfix -c abc123def urgent   # Creates worktree "urgent" with branch "hotfix" from commit SHA
 
 EOF
     kill -INT $$
@@ -64,7 +73,7 @@ function cp_cow {
 }
 
 
-# Create a worktree from a given branchname, and copy some untracked files
+# Create a worktree from a given worktree name, and copy some untracked files
 function _worktree {
     if [ -z "$1" ]; then
         usage
@@ -73,44 +82,59 @@ function _worktree {
     if [ -n "$VERBOSE" ]; then
         set -x
     fi
-    branchname="$1"
+
+    worktree_name="$1"
+
+    # If no branch name specified via -b flag, use worktree name as branch name
+    if [ -z "$BRANCH_NAME" ]; then
+        branchname="$worktree_name"
+    else
+        branchname="$BRANCH_NAME"
+    fi
 
     # Replace slashes with underscores. If there's no slash, dirname will equal
-    # branchname. So "alu/something-other" becomes "alu_something-other", but
+    # worktree_name. So "feature/something-other" becomes "feature_something-other", but
     # "quick-fix" stays unchanged
     # https://www.tldp.org/LDP/abs/html/parameter-substitution.html
-    dirname=${branchname//\//_}
+    dirname=${worktree_name//\//_}
     
     is_worktree=$(git rev-parse --is-inside-work-tree)
-    if $is_worktree; then        
-        parent_dir=".."    
-    else        
+    if $is_worktree; then
+        parent_dir=".."
+    else
         parent_dir="."
     fi
 
-    # if the branch name already exists, we want to check it out. Otherwise,
-    # create a new branch. I'm sure there's probably a way to do that in one
-    # command, but I'm done fiddling with git at this point
-    #
-    # As far as I can tell, we have to check locally and remotely separately if
-    # we want to be accurate. See https://stackoverflow.com/a/75040377 for the
-    # reasoning here. Also this has some caveats, but probably works well
-    # enough :shrug:
-    #
-    # if the branch exists locally:
-    if git for-each-ref --format='%(refname:lstrip=2)' refs/heads | grep -E "^$branchname$" > /dev/null 2>&1; then
-        if ! git worktree add "$parent_dir/$dirname" "$branchname"; then
-            die "failed to create git worktree $branchname"
+    # Validate commit-ish if provided
+    if [ -n "$COMMIT_ISH" ]; then
+        if ! git rev-parse --verify "$COMMIT_ISH^{commit}" >/dev/null 2>&1; then
+            die "Invalid commit-ish: $COMMIT_ISH"
         fi
-    # if the branch exists on a remote:
-    elif git for-each-ref --format='%(refname:lstrip=3)' refs/remotes/origin | grep -E "^$branchname$" > /dev/null 2>&1; then
-        if ! git worktree add "$parent_dir/$dirname" "$branchname"; then
-            die "failed to create git worktree $branchname"
+    fi
+
+    # Handle worktree creation based on whether commit-ish is provided
+    if [ -n "$COMMIT_ISH" ]; then
+        # When commit-ish is provided, always create a new branch from that commit-ish
+        if ! git worktree add -b "$branchname" "$parent_dir/$dirname" "$COMMIT_ISH"; then
+            die "failed to create git worktree $branchname from $COMMIT_ISH"
         fi
     else
-        # otherwise, create a new branch
-        if ! git worktree add -b "$branchname" "$parent_dir/$dirname"; then
-            die "failed to create git worktree $branchname"
+        # Original logic: check if branch exists locally/remotely, or create new
+        # if the branch exists locally:
+        if git for-each-ref --format='%(refname:lstrip=2)' refs/heads | grep -E "^$branchname$" > /dev/null 2>&1; then
+            if ! git worktree add "$parent_dir/$dirname" "$branchname"; then
+                die "failed to create git worktree $branchname"
+            fi
+        # if the branch exists on a remote:
+        elif git for-each-ref --format='%(refname:lstrip=3)' refs/remotes/origin | grep -E "^$branchname$" > /dev/null 2>&1; then
+            if ! git worktree add "$parent_dir/$dirname" "$branchname"; then
+                die "failed to create git worktree $branchname"
+            fi
+        else
+            # otherwise, create a new branch
+            if ! git worktree add -b "$branchname" "$parent_dir/$dirname"; then
+                die "failed to create git worktree $branchname"
+            fi
         fi
     fi
 
@@ -140,22 +164,22 @@ function _worktree {
     # other way around
     #
     # shellcheck disable=SC2207
-    platform=`uname`
+    platform=$(uname)
     if $is_worktree; then
         copy_source="."
     else
         copy_source=./$(git rev-parse --abbrev-ref HEAD)
     fi
     if [ "$platform" = "Darwin" ]; then
-        files_to_copy=( $(find -E $copy_source -not -path '*node_modules*' -and \
+        files_to_copy=( $(find -E "$copy_source" -not -path '*node_modules*' -and \
                 -iregex '.*\/\.(envrc|env|env.local|tool-versions|mise.toml)' ) )
     else
-        files_to_copy=( $(find $copy_source -not -path '*node_modules*' -and \
+        files_to_copy=( $(find "$copy_source" -not -path '*node_modules*' -and \
                 -regextype posix-extended -iregex '.*\/\.(envrc|env|env.local|tool-versions|mise.toml)' ) )
     fi
 
     for f in "${files_to_copy[@]}"; do
-      target_path="${f#$copy_source/}"
+      target_path="${f#"$copy_source"/}"
       cp_cow "$f" "$parent_dir/$dirname/$target_path"
     done
 
@@ -186,6 +210,14 @@ while true; do
             VERBOSE=true
             shift
             ;;
+        -b | --branch)
+            BRANCH_NAME="$2"
+            shift 2
+            ;;
+        -c | --commit)
+            COMMIT_ISH="$2"
+            shift 2
+            ;;
         *)
             break
             ;;