From 4b9823fdf7245eb594dfa93b45a16bbef75b4c44 Mon Sep 17 00:00:00 2001
From: Jack Plowman <62281988+JackPlowman@users.noreply.github.com>
Date: Sun, 14 Jun 2026 20:31:48 +0100
Subject: [PATCH 1/2] update

---
 .zshrc                                        |  3 +-
 .../scripts/squash_by_day.py                  | 46 +++++++++++++++++++
 .../scripts/squash_by_day.sh                  |  5 ++
 3 files changed, 52 insertions(+), 2 deletions(-)
 create mode 100644 development-configuration/scripts/squash_by_day.py
 create mode 100644 development-configuration/scripts/squash_by_day.sh

diff --git a/.zshrc b/.zshrc
index 0dd2f1e..91cb836 100644
--- a/.zshrc
+++ b/.zshrc
@@ -89,12 +89,11 @@ alias rebase="bash ~/development-configuration/scripts/rebase_and_push.sh"
 alias main="bash ~/development-configuration/scripts/checkout_main_and_pull.sh"
 alias master="bash ~/development-configuration/scripts/checkout_master_and_pull.sh"
 alias fetch-all="bash ~/development-configuration/scripts/fetch_all.sh"
+alias squash_by_day="bash ~/development-configuration/scripts/squash_by_day.sh"
 
 # Added by LM Studio CLI (lms)
 export PATH="$PATH:/Users/jackplowman/.lmstudio/bin"
 # End of LM Studio CLI section
 
-
-
 # Added by Antigravity CLI installer
 export PATH="/Users/jackplowman/.local/bin:$PATH"
diff --git a/development-configuration/scripts/squash_by_day.py b/development-configuration/scripts/squash_by_day.py
new file mode 100644
index 0000000..3bd0850
--- /dev/null
+++ b/development-configuration/scripts/squash_by_day.py
@@ -0,0 +1,46 @@
+# /// script
+# requires-python = ">=3.14"
+# dependencies = []
+# ///
+
+import sys
+import subprocess
+
+def main():
+    if len(sys.argv) < 2:
+        print("Usage: uv run squash_by_day.py <rebase-todo-file>")
+        sys.exit(1)
+
+    todo_file = sys.argv[1]
+
+    with open(todo_file, "r") as f:
+        lines = f.readlines()
+
+    out = []
+    prev_date = None
+
+    for line in lines:
+        if line.startswith("pick "):
+            commit_hash = line.split()[1]
+            # Look up the commit date (YYYY-MM-DD)
+            date = subprocess.check_output(
+                ["git", "log", "-1", "--format=%cd", "--date=short", commit_hash]
+            ).decode("utf-8").strip()
+
+            if prev_date == date:
+                # Same day as the previous commit, squash into it.
+                # Note: change "squash " to "fixup " below to discard the squashed commit messages.
+                out.append(line.replace("pick ", "squash ", 1))
+            else:
+                # First commit of a new day, keep it as 'pick'
+                out.append(line)
+
+            prev_date = date
+        else:
+            out.append(line)
+
+    with open(todo_file, "w") as f:
+        f.writelines(out)
+
+if __name__ == "__main__":
+    main()
diff --git a/development-configuration/scripts/squash_by_day.sh b/development-configuration/scripts/squash_by_day.sh
new file mode 100644
index 0000000..f3cf179
--- /dev/null
+++ b/development-configuration/scripts/squash_by_day.sh
@@ -0,0 +1,5 @@
+#!/bin/bash
+
+BASE_BRANCH=$(git rev-parse --abbrev-ref origin/HEAD 2>/dev/null)
+# Run the automated rebase targeting the base branch instead of HEAD~N
+GIT_SEQUENCE_EDITOR='uv run squash_by_day.py' GIT_EDITOR=true git rebase -i $BASE_BRANCH

From c6ebe5164e7cfeba28cbb71d44a4c4f242d1f61b Mon Sep 17 00:00:00 2001
From: Jack Plowman <62281988+JackPlowman@users.noreply.github.com>
Date: Sun, 14 Jun 2026 21:03:29 +0100
Subject: [PATCH 2/2] Daily squash

---
 .../scripts/squash_by_day.py                  |  46 -------
 .../scripts/squash_by_day.sh                  | 119 +++++++++++++++++-
 2 files changed, 115 insertions(+), 50 deletions(-)
 delete mode 100644 development-configuration/scripts/squash_by_day.py

diff --git a/development-configuration/scripts/squash_by_day.py b/development-configuration/scripts/squash_by_day.py
deleted file mode 100644
index 3bd0850..0000000
--- a/development-configuration/scripts/squash_by_day.py
+++ /dev/null
@@ -1,46 +0,0 @@
-# /// script
-# requires-python = ">=3.14"
-# dependencies = []
-# ///
-
-import sys
-import subprocess
-
-def main():
-    if len(sys.argv) < 2:
-        print("Usage: uv run squash_by_day.py <rebase-todo-file>")
-        sys.exit(1)
-
-    todo_file = sys.argv[1]
-
-    with open(todo_file, "r") as f:
-        lines = f.readlines()
-
-    out = []
-    prev_date = None
-
-    for line in lines:
-        if line.startswith("pick "):
-            commit_hash = line.split()[1]
-            # Look up the commit date (YYYY-MM-DD)
-            date = subprocess.check_output(
-                ["git", "log", "-1", "--format=%cd", "--date=short", commit_hash]
-            ).decode("utf-8").strip()
-
-            if prev_date == date:
-                # Same day as the previous commit, squash into it.
-                # Note: change "squash " to "fixup " below to discard the squashed commit messages.
-                out.append(line.replace("pick ", "squash ", 1))
-            else:
-                # First commit of a new day, keep it as 'pick'
-                out.append(line)
-
-            prev_date = date
-        else:
-            out.append(line)
-
-    with open(todo_file, "w") as f:
-        f.writelines(out)
-
-if __name__ == "__main__":
-    main()
diff --git a/development-configuration/scripts/squash_by_day.sh b/development-configuration/scripts/squash_by_day.sh
index f3cf179..02b137e 100644
--- a/development-configuration/scripts/squash_by_day.sh
+++ b/development-configuration/scripts/squash_by_day.sh
@@ -1,5 +1,116 @@
-#!/bin/bash
+#!/usr/bin/env bash
+set -euo pipefail
 
-BASE_BRANCH=$(git rev-parse --abbrev-ref origin/HEAD 2>/dev/null)
-# Run the automated rebase targeting the base branch instead of HEAD~N
-GIT_SEQUENCE_EDITOR='uv run squash_by_day.py' GIT_EDITOR=true git rebase -i $BASE_BRANCH
+usage() {
+  cat <<'EOF'
+Usage: squash-commits-by-day.sh [BASE]
+
+Rebase the current branch onto BASE, then combine its commits by author date.
+Each resulting commit is named "Squash for YYYY-MM-DD".
+
+When BASE is omitted, the script tries origin/HEAD, main, then master.
+
+The selected history must be linear and the worktree must be clean.
+This command rewrites Git history and does not create a backup branch.
+EOF
+}
+
+die() {
+  printf 'Error: %s\n' "$*" >&2
+  exit 1
+}
+
+if [[ ${1:-} == "-h" || ${1:-} == "--help" ]]; then
+  usage
+  exit 0
+fi
+
+(( $# <= 1 )) || die "expected at most one BASE argument"
+git rev-parse --git-dir >/dev/null 2>&1 || die "not inside a Git repository"
+git symbolic-ref -q HEAD >/dev/null || die "HEAD must be attached to a branch"
+[[ -z $(git status --porcelain) ]] || die "worktree and index must be clean"
+
+branch=$(git symbolic-ref --short HEAD)
+
+if [[ $# == 1 ]]; then
+  base_ref=$1
+else
+  base_ref=""
+  remote_default=$(git symbolic-ref -q --short refs/remotes/origin/HEAD || true)
+  for candidate in "$remote_default" main master; do
+    if [[ -n $candidate ]] && git rev-parse --verify "$candidate^{commit}" >/dev/null 2>&1; then
+      base_ref=$candidate
+      break
+    fi
+  done
+  [[ -n $base_ref ]] || die "could not detect a default branch; pass BASE explicitly"
+fi
+
+base=$(git rev-parse --verify "$base_ref^{commit}") || die "invalid BASE: $base_ref"
+[[ $base != $(git rev-parse HEAD) ]] || die "current branch is already at BASE ($base_ref)"
+
+printf 'Rebasing %s onto %s...\n' "$branch" "$base_ref"
+if ! git rebase "$base_ref"; then
+  die "rebase stopped; resolve conflicts and run 'git rebase --continue' or abort it"
+fi
+
+base=$(git rev-parse --verify "$base_ref^{commit}")
+old_head=$(git rev-parse HEAD)
+revision_range="$base..HEAD"
+
+commits=()
+while IFS= read -r commit; do
+  commits+=("$commit")
+done < <(git rev-list --reverse --topo-order "$revision_range")
+
+(( ${#commits[@]} > 0 )) || die "no commits to rewrite"
+
+for commit in "${commits[@]}"; do
+  parents=$(git rev-list --parents -n 1 "$commit")
+  [[ $(wc -w <<<"$parents" | tr -d ' ') -le 2 ]] || \
+    die "selected history contains merge commit $commit"
+done
+
+new_parent=$base
+group_date=""
+group_last=""
+
+create_group_commit() {
+  local commit=$1 day=$2 tree author_name author_email author_date new_commit
+  tree=$(git rev-parse "$commit^{tree}")
+  author_name=$(git show -s --format=%an "$commit")
+  author_email=$(git show -s --format=%ae "$commit")
+  author_date=$(git show -s --format=%aI "$commit")
+
+  if [[ -n $new_parent ]]; then
+    new_commit=$(printf 'Squash for %s\n' "$day" | \
+      GIT_AUTHOR_NAME="$author_name" GIT_AUTHOR_EMAIL="$author_email" \
+      GIT_AUTHOR_DATE="$author_date" GIT_COMMITTER_DATE="$author_date" \
+      git commit-tree "$tree" -p "$new_parent")
+  else
+    new_commit=$(printf 'Squash for %s\n' "$day" | \
+      GIT_AUTHOR_NAME="$author_name" GIT_AUTHOR_EMAIL="$author_email" \
+      GIT_AUTHOR_DATE="$author_date" GIT_COMMITTER_DATE="$author_date" \
+      git commit-tree "$tree")
+  fi
+  new_parent=$new_commit
+}
+
+for commit in "${commits[@]}"; do
+  commit_date=$(git show -s --format=%aI "$commit")
+  commit_date=${commit_date:0:10}
+
+  if [[ -n $group_date && $commit_date != "$group_date" ]]; then
+    create_group_commit "$group_last" "$group_date"
+  fi
+  group_date=$commit_date
+  group_last=$commit
+done
+create_group_commit "$group_last" "$group_date"
+
+git update-ref "refs/heads/$branch" "$new_parent" "$old_head"
+git reset --hard "$new_parent" >/dev/null
+
+printf 'Rebased and rewrote %s onto %s.\n' "$branch" "$base_ref"
+git log --oneline --decorate --date=short --format='%h %ad %s' \
+  ${base:+"$base.."}HEAD