Generate git-rebase-todo-list to squash similar commits

generate-multiple-new-file-squashes.sh

# Warning: Due to child_hash optimisation this doesnt support merges

# Usable with GIT_EDITOR='touch'
# TODO: Create a better GIT_EDITOR command that
# strips only blank lines in commit body
# TODO: Support merges

# different levels of merging:
author_tag_format="%ae"
same_author_day_tag_format="%ae-%ad"
almost_identical_tag_format="%ae-%ad-%f"

# chosen level
tag_format="$author_tag_format"

consecutive_file_list=/tmp/consecutive_file_list.txt

git rev-list --all --children > /tmp/children_rev_list.txt

git log --pretty=tformat:"%H ${tag_format}" --date=short --reverse | (
  prev_hash=""
  prev_tag=""
  prev_only_adds_files=""

  while read line; do
    set $line
    hash="$1"
    tag="$2"

    only_adds_files=""
    if [ "$tag" = "$prev_tag" ]; then
      if git diff-tree --no-commit-id --name-status -r "$hash" | grep -qv '^A' ; then
        true
      else
        only_adds_files="true"
        if [ -z "$prev_only_adds_files" ]; then
          if git diff-tree --no-commit-id --name-status -r "$prev_hash" | grep -qv '^A' ; then
            true
          else
            git diff-tree --no-commit-id --name-only -r "$prev_hash" > $consecutive_file_list
            prev_only_adds_files="true"
          fi
        fi
        if [ "$prev_only_adds_files" = "true" ]; then
          git diff-tree --no-commit-id --name-only -r "$hash" >> $consecutive_file_list
        fi
      fi
    fi

    if [ -z "$prev_hash" ]; then
      echo "# rebasing onto $hash : $tag"
    elif [ "$tag" = "$prev_tag" -a -n "$only_adds_files" -a -n "$prev_only_adds_files" ]; then
      echo "squash $hash $tag"

      # Peek ahead at the child hash; not very efficient here
      child_hash=$(grep "^$hash" /tmp/children_rev_list.txt | cut -d ' ' -f 2)
      # If child hash wont be another squash, it is time to write a better commit message
      if git diff-tree --no-commit-id --name-status -r "$child_hash" | grep -qv '^A' ; then
        echo -n "exec git commit --amend -m 'Added consecutive files'"
        cat $consecutive_file_list | while read line; do
          printf " -m %q" "$line"
        done
        echo ""
      fi
    else
      echo "pick $hash $tag"
    fi

    prev_hash="$hash"
    prev_tag="$tag"
    prev_only_adds_files="$only_adds_files"
  done
)

generate-similiar-commit-squashes.sh

# Use with
# echo 'print if ! $x{$_}++' > /tmp/strip-seen-lines.pl
# GIT_EDITOR='perl -i -n -f /tmp/strip-seen-lines.pl'

# different levels of merging:
author_tag_format="%ae"
almost_identical_tag_format="%ae-%ad-%f"

# chosen level
tag_format="$almost_identical_tag_format"

git log --pretty=tformat:"%H ${tag_format}" --date=short --reverse | (
  prev_hash=""
  prev_tag=""

  while read line; do
    set $line
    hash=$1
    tag=$2

    if [ -z "$prev_hash" ]; then
      echo "# rebasing onto $hash : $tag"
    elif [ "$tag" = "$prev_tag" ]; then
      echo "squash $hash $tag"
    else
      echo "pick $hash $tag"
    fi

    prev_hash=$hash
    prev_tag=$tag
  done
)