Possible incompatibility with Jekyll 4.0.0

Description:

It seems that jekyll-admin isn’t proper configured to run with Jekyll 4.0.0.

Tell us a bit about yourself:

• Version of JekyllAdmin: v0.8.1
• Version of Jekyll: possibly v4.0.0 (because bundle show also returns the same error)
• Version of NodeJS: v12.7.0
• Operating System: Ubuntu 18.04 64bits

Steps to reproduce:

After correctly installing Jekyll on my computer and running a test instance with no issues, I created the _plugins directory and installed Jekyll Admin through:

• adding - jekyll-adminto the “plugins” section on _config.yml
• running gem install jekyll-admin
• adding it to the :jekyll_plugins group in the Gemfile
• and, finally, running bundle install
• tried to run bundle exec jekyll serve

I expected the following:

I expected to receive no errors, to be able to go to http://localhost:4000/admin

But got the following, instead:

When running bundle exec jekyll serve, it returns:

Bundler could not find compatible versions for gem "jekyll":
  In snapshot (Gemfile.lock):
    jekyll (= 4.0.0)

  In Gemfile:
    jekyll (~> 4.0.0)

    jekyll-admin was resolved to 0.8.1, which depends on
      jekyll (~> 3.3)

Running `bundle update` will rebuild your snapshot from scratch, using only
the gems in your Gemfile, which may resolve the conflict.

Other details:

The error persists even after running bundle update

[ashmaroli]

jekyll-admin-0.9.0 with support for Jekyll 4.0 has been released.

[mattboy9921]

Alright, I’ve managed to get jekyll-admin to work on Jekyll 4.0.0. It’s a silly, hacky way to do it but it does work.

1. Edit your Gemfile Jekyll version to 3.8.6 and make sure jekyll-admin is in the plugin section.
2. Run bundle update to get everything downloaded and working.
3. Assuming you’ve installed Jekyll with Bundle via the tutorial on Jekyll’s site, cd into ./vendor/bundle/ruby/2.5.0/specifications and edit jekyll-admin-0.8.1.gemspec so both instances of jekyll have their version set to 4.0.0.
4. cd back to your Jekyll site directory and edit your Gemfile so Jekyll is at 4.0.0.
5. Run bundle update again. It didn’t redownload everything, just Jekyll so the changes to jekyll-admin’s dependencies stuck. I also noticed there is a --local option for bundle update which forces using local cache but I didn’t try it.

Doing this, I can now have Jekyll 4.0.0 with jekyll-admin and so far, I can’t find any issues. So maybe this is just a matter of updating the dependency string to include 4.0.0?