BASH Slugify

It slugifies strings. In your BASH. Well, I need to clean filenames — like uploaded images — regularly and this helps me automate it.

What's happening?

Optionally convert to upper- or lower case (default: no change).
Optionally all special chars ([^a-zA-Z0-9]) are removed or replaced (default: _).
Optionally all or some glue characters ([-_.]) are replaced with spaces.
Whitespace is consolidated and trimmed.
All remaining spaces are replaced (default: -).

Examples

$ ./slugify.sh foo 'Hello World!' Bar
foo
Hello-World!
Bar

$ ./slugify.sh foo -l 'Hello World!' Bar
foo
hello-world!
bar

$ ./slugify.sh -e foo 'Hello World!' Bar
foo-Hello-World!-Bar

$ ./slugify.sh -exl foo Hello World! Bar
foo-hello-world-bar

If you use the -r switch, arguments are threated as file names to be slugifed (and renamed). Here's the output if you run it dry (no renaming) in the directory of this repository — $ ./slugify.sh -rn -lx *:

CHANGELOG.md -> changelog.md
LICENSE -> license
README.md -> readme.md
src -> skipped (no change)
tests -> skipped (no change)

Usage

Slugifies strings or filenames.

usage: slugify [(l|u)|(x|X)|E|D|U|P|A|S|(c< char>|s)|C< char>|e|r|n|f|v|d|h]… <string>…

character options
  -l  convert to lowercase
  -u  convert to uppercase
  -x  remove special chars
  -X  replace special chars

space options
  -D  don't convert dashes to spaces
  -U  don't convert underscores to spaces
  -P  don't convert dots (points) to spaces
  -A  don't remove spaces around dashes and underscores
  -S  don't consolidate multiple spaces

replacement options
  -c <char> replace all spaces with this (default: '-')
  -C <char> replace special chars with this (default: '_')
  -s use underscores for spaces (shortcut for '-c_')

mode options
  -e  extended — treat all arguments as one string and echo one slug for it
  -r  rename files – treat arguments as filenames and rename them

rename options
  -E  don't slugify file extensions
  -n  dry run — only show new file names (no renaming)
  -f  force — overwrite existing files

other options
  -v  verbose output
  -d  debug output
  -h  print help

Return Values

0 all went well
1 error parsing arguments
2 original string is empty
3 slugified string is empty
4 original file not found
5 slugified file exists

Development

Tested with Bats. Okay just barely…