BYO - Protocols for Test Discovery, Shell Completion

BYO is a simple mechanism to turn CLI processes into "servers" which respond to requests encoded in environment variables.

Points of reference:

Test Anything Protocol
- e.g. Perl scripts parse stdout of test processes in any language
Shellac Protocol Proposal V2 (wiki, 2019)

(About the name: It originally stood for Bash YSH OSH. But "bring your own" is a good acronym!)

Table of Contents

The General Idea

Executables should respond to the BYO_COMMAND environment variable:

BYO_COMMAND=foo

And BYO_ARG=bar varies based on the command.

A library that implements this is:

source $LIB_OSH/byo-server.sh

But it's designed to be implemented in Python, C++, etc.

A client is:

test/byo-client.sh detect myscript.sh

Here's how you detect if an executable supports BYO:

$ BYO_COMMAND=detect ./any-executable </dev/null
list-tests
run-tests

# must exit with code 66, which is ASCII 'B'

List tests first:

BYO_COMMAND=list-tests

Then run them one at a time:

BYO_COMMAND=run-test
BYO_ARG=foo

TODO:

BYO_COMMAND=list-tasks  # related to task-five
BYO_COMMAND=list-flags  # only some binaries have flags

The tool should work like this:

$ byo detect myscript.sh
$ byo test myscript.sh

Runtime:

Points of reference:

Instead of a fresh process env variables, we might want to detect coprocesses.

Generated on Fri, 01 Nov 2024 01:42:41 +0000