amphtml-validator CLI fails on Mac OS X

[uncompiled]

When running amphtml-validator from the command line on Mac OS X, the following error occurs:

$ amphtml-validator https://www.ampproject.org/
readlink: illegal option -- f
usage: readlink [-n] [file ...]

How do we reproduce the issue?

1. On a Mac, run npm install -g amphtml-validator
2. Run amphtml-validator https://www.ampproject.org/

readlink behaves differently on a Mac, so index.sh fails.

A workaround is to brew install coreutils and use greadlink instead.

[dvoytenko]

/to @powdercloud

[ericlindley-g]

@powdercloud — Slotting in "pending triage" for now. please update the milestone when you have a sense of when work will start. Thanks!

[powdercloud]

Thanks much for saying hi and reporting this. Sorry I've never used a Mac, that's why this happened.

We should to make this portable. Two ideas:

• Use this recipe to implement a readlink -f substitute shell function: http://stackoverflow.com/questions/1055671/how-can-i-get-the-behavior-of-gnus-readlink-f-on-a-mac
• Use the Node.js interpreter since it comes with a nice fs package, so it ought to be possible to make a one-liner for readlink -f.

I'm in the midst of something right now but will look into this in a while unless someone else posts a solution first.

[powdercloud]

I posted a PR which uses the second approach. Thanks in advance for any feedback. The action item that remains is to verify this fix works on a Mac.

#4269

[powdercloud]

Thanks for your help @uncompiled.
version 1.0.10 with the fix pushed to npmjs.com.