Pulldozer

Pulldozer is a simple CLI tool for batch editing multiple GitHub repos.

You give Pulldozer a transformation script and it spits out pull requests. There are no other side effects - your existing local repos will remain untouched.

Usage

Clone this repo onto any Unix machine that has curl. Set your GITHUB_TOKEN environment variable to an access token with repo scope and SSO enabled.

To perform a batch edit:

1. Specify your desired COMMIT_MESSAGE string, REPOS list, and transform function in a shell script:

   COMMIT_MESSAGE='Fix "langauge" typos'
   
   transform() { # $1=org name, $2=repo name
     # Replace all occurrences of "langauge" with "language"
     git grep --cached -z -l '' | xargs -0 gsed -i 's/langauge/language/g'
   }
   
   REPOS='
   artnc/dotfiles
   duolingo/halflife-regression
   duolingo/rtl-viewpager
   '
   
   # Optional: Markdown to include in pull request description
   DESCRIPTION='[Correct spelling](https://en.wiktionary.org/wiki/language)'

   Shell skills rusty? Click here for a cheat sheet.

   • List all Git-tracked files containing $needle with git grep --cached -l $needle
     • To simply list all files, specify -l ''
     • -z will use \0 instead of newline as the delimiter
       • Required if you'll be piping paths containing whitespace into xargs
     • Symlinks and submodules are excluded
   • Pipe a file list into xargs $command to run $command $file on each file in the list
     • Use xargs -0 if the input is \0-delimited rather than newline-delimited
   • Replace strings in a file with gsed -i -e 's/myRegex/mySubstitution/g' $file
     • You can use any character in place of / as the delimiter if conflicts arise
     • You can specify -E and then reference parenthesized capture groups with \1 etc.
     • You can declare multiple substitutions by placing -e before each one
     • To replace newlines, add -e ':a' -e 'N' -e '$!ba' before your own -e 's/\n/foobar/g'
   Really want to use some other language? Click here for a Python example.

   The transform functions below will add a spring.application.name=$REPO_NAME line immediately after the app.environment line in all files matching src/main/resources/*.properties that don't already contain a spring.application.name line.

   • Python version:

     transform() {
       python3 - << EOF
     import re
     import subprocess
     
     git_paths = subprocess.check_output("git grep --cached -l ''", shell=True)
     for path in git_paths.decode().splitlines():
         if not re.search(r'^src/main/resources/.*\.properties$', path):
             continue
         with open(path) as f:
             contents = f.read()
         if re.search(r'spring\.application\.name', contents):
             continue
         with open(path, 'w') as f:
             f.write(re.sub(r'(app\.environment=\w*)', r'\1\nspring.application.name=${2}', contents))
     EOF
     }

   • Shell version:

     transform() {
       for path in $(git grep --cached -l ''); do
         if ! printf %s "${path}" | grep -qE '^src/main/resources/.*\.properties$'; then
           continue
         fi
         if grep -qF 'spring.application.name' "${path}"; then
           continue
         fi
         sed -E -i "s/(app\.environment=\w*)/\1\nspring.application.name=${2}/g" "${path}"
       done
     }

2. Run ./pulldozer /path/to/script.sh. (To use Bash in your transformation script, prepend bash to that command - otherwise Pulldozer assumes POSIX sh.) Pulldozer will ask for confirmation and then open PRs, each of which will contain your transformation script in its description.

   

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