Steel Overseer

A file watcher and development tool, similar to Ruby's Guard.

Forked and extended from https://github.com/schell/steeloverseer

Installation

Download and install the stack build tool.

git clone https://github.com/mitchellwrosen/steeloverseer.git
cd steeloverseer
stack install

This will create a binary deep inside ~/.stack/, and symlink to it at ~/.local/bin/sos.

Usage

sos requires a directory to watch, a list of commands to run, and an optional list of regex patterns to match on file paths (see sos --help for details).

Capture groups can be created with ( ) and captured variables can be referred to with {1}, {2}, etc. ({0} contains the entire match).

For example, for each change to a .c file in src/, we may want to compile the file and run its corresponding unit test:

sos src/ -c "gcc -c {0} -o obj/{1}.o" -c "make test --filter=test/{1}_test.c" -p "src/(.*)\.c"

Commands are run left-to-right, and one failed command will halt the entire pipeline.

As a shortcut, we may want to write the above only once and save it in .sosrc, which is an alternative to the command-line interface (yaml syntax):

- pattern: src/(.*)\.c
  commands:
  - gcc -c {0} -o obj/{1}.o
  - make test --filter=test/{1}_test.c

Pipelines of commands are immediately canceled and re-run if a subsequent filesystem event triggers the same list of commands. Otherwise, commands are are enqueued and run sequentially to keep the terminal output clean and readable.

For example, we may wish to run hlint on any modified .hs file:

- pattern: .*\.hs
  commands:
  - hlint {0}

We can modify foo.hs and trigger hlint foo.hs to run. During its execution, modifying bar.hs will enqueue hlint bar.hs, while modifying foo.hs again will re-run hlint foo.hs.