• Whitespace Total Fixer
  • Why you should use it
  • Quick Install
  • How to use it
  • Git pre-commit hooks
    • Careful version
    • Simple version
• Exciting origin story
• Whitespace issues addressed
• Reporting
• Todo
• Bugs
• Author
• License

Identifies and/or fixes inconsistent whitespace and line endings in text files, so that they don't clog up your commits to version control systems like Git, Mercurial, or Subversion.

• It's like an incomprehensible shell-script one-liner (e.g. sed -e 's/LINENOISE/'), but way better
• It's similar to git stripspace, but more flexible and detailed.
• wtf.py is a simple Python2 script (tested with 2.7.5) with no dependencies beyond the standard Python library.

curl https://raw.githubusercontent.com/dlenski/wtf/master/wtf.py > ~/bin/wtf.py && chmod 0755 !#:3

See below for options to control exactly which whitespace issues it fixes, but here are some examples:

# consistent whitespace from programs that generate text files
dump_database_schema | wtf.py -o clean_output.sql

# in-place editing
wtf.py -i file1.txt file2.txt file3.txt
wtf.py -I.bak file1.txt file2.txt file3.txt # ditto, with backups

# summarize a bunch of files without actually editing them (-0)
find . -name "*.txt" -exec wtf.py -0 {} \;

# more advanced: find interesting text files. pass options and a directory
wtf-find() {
    find "${@: -1}" -not \( -name .svn -prune -o -name .git -prune \
         -o -name .hg -prune \) -type f -exec bash -c \
         'grep -Il "" "$1" &>/dev/null && wtf.py '"${*:1:$#-1}"' "$1"' _ {} \;
}
wtf-find -0 .

# exit status
wtf.py file1.txt file2.txt file3.txt > /dev/null
if (( $? == 10 )); then
  echo "issues fixed"
elif (( $? == 20 )); then
  echo "unfixed issues!"
fi

You can use Git pre-commit hooks to automatically run wtf and cleanup whitespace in your repository prior to every commit. (You can bypass the hook, however, with git commit -n.)

Create the file .git/hooks/pre-commit in your repository, and ensure that it is executable (chmod +x .git/hooks/pre-commit).

This version will run wtf, with the default options, on all the to-be-committed text files. It operates only on the contents of the index ("staging area"), so it will play nicely with git add --patch and the files in your working tree won't be modified. Note that when a file changes in your commit but remains unchanged in your working tree, the file will be marked modified by git status immediately after the commit.

This version will run wtf with -i and any options you add, on all the to-be-committed text files. They will be cleaned up in the commit, as well as in your working tree. This version will not play nicely with git add --patch.

#!/bin/sh
wtf_options='-i'

# get a list of to-be-committed filepaths, EXCLUDING files considered
# by Git to be binary
committees=$(git diff --cached --numstat --diff-filter=ACMRTU|egrep -v ^-|cut -f3-)

# Run Whitespace Total Fixer in-place, and re-add files modified by it
for committee in $committees
do
	wtf $wtf_options "$committee" || git add "$committee"
done

One day at work, I spent way too much time wrangling commits laden with whitespace issues generated by recalcitrant text-editing tools on multiple platforms.

That evening, I went home and spent way too much time writing this program instead!

WTF currently fixes, or simply reports, a few common types of whitespace issues. Most of these issues offer three possible command-line options enabling the user to fix, report, or ignore the issue.

• Remove trailing spaces at the ends of lines (default is fix):

    -t, --trail-space
    -T, --report-trail-space
    -It, --ignore-trail-space
  

• Remove blank lines at the ends of files (default is fix):

    -b, --eof-blanks
    -B, --report-eof-blanks
    -Ib, --ignore-eof-blanks
  

• Ensure that a new-line character appears at the end of the file (default is fix):

    -n, --eof-newl
    -N, --report-eof-newl
    -In, --ignore-eof-newl
  

• Make sure that all lines have matching EOL markers (that is, no mixing of lf/crlf). Default is to fix non-matching EOL characters by making them all the same as the first line of the file. The desired EOL markers can also be set to a specific value (lf/crlf/native), in which case all lines will unconditionally receive this marker.

    -E ENDING, --coerce-eol ENDING
    -e ENDING, --expect-eol ENDING
    -Ie, --ignore-eol
  

• Check for spaces followed by tabs in the whitespace at the beginning of a line; fixing this condition requires setting either --change-tabs or --change-spaces. The default is to report and warn:

    -s, --tab-space-mix
    -S, --report-tab-space-mix
    -Is, --ignore-tab-space-mix
  

• Change tabs in the whitespace at the beginning of a line to the specified number of spaces (default is not to change tabs at all). This option will not touch leading tabs when they are mixed with spaces, unless --tab-space-mix is also specified.

    -x SPACES, --change-tabs SPACES
  

• Change the specified number of consecutive spaces in the whitespace at the beginning of a line to tabs (default is not to change spaces at all). This option will not touch leading tabs when they are mixed with spaces, unless --tab-space-mix is also specified.

    -y SPACES, --change-spaces SPACES
  

Unless the -q/--quiet option is used, WTF will summarize each file processed in which any whitespace issues were found and/or fixed. With -v it will also report issue-free files.

$ wtf -0 nightmare.txt    # -0 is equivalent to > /dev/null
nightmare.txt LINE 8: WARNING: spaces followed by tabs in whitespace at beginning of line
nightmare.txt:
    CHOPPED 1 lines with trailing space
    CHOPPED 0 blank lines at EOF
    ADDED newline at EOF
    CHANGED 1 line endings which didn't match crlf from first line
    WARNED ABOUT 1 lines with tabs/spaces mix

WTF will return the following exit codes on successful operation:

• 0: no issues seen (or -X/--no-exit-codes specified)
• 10: issues fixed
• 20: unfixed issues seen

• Stability tests?
• Unicode tests?

Corrupts source code files written in the Whitespace programming language.

Anything else?

© Daniel Lenski <dlenski@gmail.com> (2014-2016)

GPL v3 or later