Git's pre-commit hook to remove trailing whitespaces/tabs Raw

pre-commit

#!/bin/sh
#
# This will remove the trailing whitespaces from the files and add it again to be committed.
#
# Put this into ~/.git-templates/hooks/pre-commit, and chmod +x it.

# Detect platform
platform="win"
uname_result=`uname`
if [ "$uname_result" = "Linux" ]; then
  platform="linux"
elif [ "$uname_result" = "Darwin" ]; then
  platform="mac"
fi

if git rev-parse --verify HEAD >/dev/null 2>&1; then
  against=HEAD
else
  # Initial commit: diff against an empty tree object
  against=4b825dc642cb6eb9a060e54bf8d69288fbee4904
fi

# Remove trailing whitespaces
if test "$(git diff-index --check --cached $against --)"; then
  echo "Removing trailing whitespaces..."

  for FILE in `git diff-index --check --cached $against -- | sed '/^[+-]/d' | cut -d: -f1 | uniq`; do 
    echo "* $FILE" ; 

    # Replace trailing spaces
    if [ "$platform" == "win" ]; then
      # in windows, `sed -i` adds ready-only attribute to $file(I don't kown why), so we use temp file instead
      sed 's/[[:space:]]*$//' "$FILE" > "${FILE}.tmp"
      mv -f "${FILE}.tmp" "$FILE"
    elif [ "$platform" == "mac" ]; then
      sed -i "" 's/[[:space:]]*$//' "$FILE"
    else
      sed -i 's/[[:space:]]*$//' "$FILE"
    fi

    git add "$FILE"
  done
fi

# Now we can commit
exit