ddf

discard directories fast

Important

mvs directories and files to $TMPDIR for quick cleanup

Why

I wanted to try out OCaml 5 and with the new stable eio library. Also, clearing out node_modules and other build artifacts with rm -rf takes too long.

Usage

The main form of input is a list of directories and/or files as a space separated list of arguments.

For best results, compose with fd or find to ensure correctly matching items on your file system.

Cleanup node_modules across a monorepo

ddf $(fd -t d -d 3 -a --no-ignore --prune node_modules)

Cleanup local opam/dune deps

ddf _opam _build

Get help.

ddf --help

Output example:

DDF(1)                            Ddf Manual                            DDF(1)

NAME
       ddf - `mv`s directories and files to `$TMPDIR` for quick cleanup

SYNOPSIS
       ddf [-i] [--yolo] [OPTION]… FILE/DIR…

DESCRIPTION
       ddf discards each specified FILE/DIR by moving it to a directory in
       `$TMPDIR`, listed below.

       Discarded FILE/DIRs are moved to this directory:
       /var/ddf

       To discard a FILE/DIR whose name starts with a -, for example -foo, use
       one of these commands:

       ddf -- -foo
       ddf ./-foo

OPTIONS
       -i  Prompt before every operation.

       -y, --yolo
           Ignore nonexistent files and never prompt.

COMMON OPTIONS
       --help[=FMT] (default=auto)
           Show this help in format FMT. The value FMT must be one of auto,
           pager, groff or plain. With auto, the format is pager or plain
           whenever the TERM env var is dumb or undefined.

       --version
           Show version information.

EXIT STATUS
       ddf exits with:

       0   on success.

       123 on indiscriminate errors reported on standard error.

Setup

1. Install opam.

   Opam will be used to install dependencies. One such dependency is dune, the build tool.

   You may have dune locally on your own system, but for consistency, we will use opam exec to run dune within the context of the local switch.

2. Create a local switch with opam

   opam switch create . --deps-only --with-test

   This command will read all the *.opam files and download all dependencies.

   You will be prompted along the process.

3. Build CLI with dune from the local switch

   opam exec -- dune build bin

4. Verify ddf.exe

   eza --tree ./_build/default

   ./_build/default
   ├── bin
   │  ├── ddf.exe # 👈
   │  ├── ddf.ml
   │  └── ddf.mli
   ├── ddf.dune-package
   ├── ddf.install
   ├── ddf.opam
   ├── lib
   │  ├── lib.a
   │  ├── lib.cma
   │  ├── lib.cmxa
   │  ├── lib.cmxs
   │  └── lib.ml
   ├── test
   │  ├── test.exe
   │  ├── test.ml
   │  └── test.mli
   ├── test.dune-package
   ├── test.install
   └── test.opam

For production, be sure to include the release flag:

opam exec -- dune build --profile release bin

Development

Run dune in watch mode to get a fast development feedback loop.

opam exec -- dune exec bin/ddf.exe --watch -- --help

Testing

Tests are organied into their own dune project.

Currently, unit tests with Alcoltest are used.

opam exec -- dune runtest

Execution

Once the built with dune, you can invoke the executable directly:

./_build/default/bin/ddf.exe --help

or with dune

opam exec -- dune exec/bin/ddf.exe -- --help

If you are consuming the binary from the build artifacts, ensure you allow the ddf.exe to be executable:

chmod +x ddf.exe

Installation

MacOS

Install from release page for your environment. Be mindful of the platform architecture.

Important

If you have an M-series Mac, you must download the *-macos-latest-arm64 build.

On MacOS, extract the binary to a location you prefer, like usr/bin.

Rename the file to drop the .exe

mv ./ddf.exe ddf

Allow the application to be executable

chmod +x ddf

Attempt to run the help page and acknowledge the OS prompt

./ddf --help

Press Cancel

Open System Preferences

Scroll down to Security section, allow ddf

Attempt to run ddf again

Acknowledge, AGAIN that we want to run this program

Return to see the output of the help page shown in your terminal.

From now on you can invoke the binary without all the interruptions.

Link ddf on your system $PATH.

Note that this assumes you have the ddf binary in the /usr/bin/ directory as such:

 eza --tree /usr/bin/
.
├── ddf

You may choose a directory of your own choosing.

Add the following to your .bashrc equivalent.

export DDF_HOME="/usr/bin/ddf"
export PATH="$DDF_HOME:$PATH"

Reload or source and you should now be able to execute ddf anywhere in your shell.

Questions and Answers

Where is everything moved to?

The tmp directory is defined via the OCaml Filename module in the standard library:

The name of the temporary directory: Under Unix, the value of the TMPDIR environment variable, or "/tmp" if the variable is not set. Under Windows, the value of the TEMP environment variable, or "." if the variable is not set. ..

ddf creates a child directory (called "ddf") to use as the destination for all discarded items.

Prior art

• rip
• mvf The first prototype of this same functionality in ReasonML without the nice CLI. If I can ever get the build tooling right, it would be nice to have Pastel back in the mix somehow. Maybe a single module for rendering CLI output prompts in ReasonML with native jsx? 🤔