Ruplacer

Find and replace text in source files.

Installing with cargo

Install rust and cargo, for example with rustup.

Then run:

cargo install ruplacer

Alternative installation methods

• Pre-compiled binaries for Linux, macOS and Windows are available as assests of the latest release.

• ruplacer can also be installed from homebrew:

$ brew install supertanker/homebrew-repo/ruplacer

• ruplacer is also on the Arch Linux User Repository

Basic usage

ruplacer pattern replacement [path]

If path is not given, it defaults to the current working directory.

Ruplacer will then walk through every file in <path>, while honoring .gitignore files found on the way.

Binary files and text files containing non-UTF8 characters will be skipped. Then for every remaining file, it will read the contents, replace all lines matching the pattern by the replacement, and print the difference:

$ replacer old new src/
Patching src/a_dir/sub/foo.txt
-- old is everywhere, old is old
++ new is everywhere, new is new

Patching src/top.txt
-- old is nice
++ new is nice

If you are OK with the replacements, re-run ruplacer with the --go option to actually write the files.

By default, pattern will be compiled into a Rust regex.

Note that it's slightly different from Perl-style regular expressions. Also, you must use $1, $2 to reference groups captures in pattern in replacement.

For instance, to replace dates looking like MM/DD/YYYY to YYYY-MM-DD, you would use:

$ ruplacer '(\d{2})/(\d{2})/(\d{4})' '$3-$1-$2'

Customizing the replacement algorithm

• Use --no-regex to prevent ruplacer from interpreting the pattern as a regex.
• Use --subvert to perform replacements across a variety of case styles:

$ ruplacer --subvert foo_bar spam_eggs
Patching src/foo.txt
-- foo_bar, FooBar, and FOO_BAR!
++ spam_eggs, SpamEggs, and SPAM_EGGS!