Including gems in build.gradle

[paulvickers]

In the asciidoc-diagram-to-html-example/build.gradle we find a way to include a gem in the build:

...
dependencies {
    gems 'rubygems:asciidoctor-diagram:1.4.0'
}

asciidoctorj {
    version = '1.5.4'
}

asciidoctor {
    dependsOn jrubyPrepare
    requires = ['asciidoctor-diagram']
    gemPath = jrubyPrepare.outputDir
...

I would like to use asciidoctor-mathematical in the pdf task of my own build.gradle. So, as a test, I replaced the asciidoctor-diagram references with asciidoctor-mathematical:

 ...
dependencies {
    gems 'rubygems:asciidoctor-mathematical:0.0.5'
}

asciidoctorj {
    version = '1.5.4'
}

asciidoctor {
    dependsOn jrubyPrepare
    requires = ['asciidoctor-mathematical']
    gemPath = jrubyPrepare.outputDir
...

I get the error:

Execution failed for task ':pdf'.
> (LoadError) no such file to load -- asciidoctor-mathematical

Is this a problem with my gem environment (brew upgrade seemed to mess things up yesterday) or is it an issue with asciidoctor-gradle?

gem list reveals:

addressable (2.4.0)
afm (0.2.2)
Ascii85 (1.0.2)
asciidoctor (1.5.4)
asciidoctor-diagram (1.5.1)
asciidoctor-epub3 (1.5.0.alpha.6)
asciidoctor-mathematical (0.0.5)
asciidoctor-pdf (1.5.0.alpha.12)
asciimath (1.0.4)
bibtex-ruby (4.4.2)
bigdecimal (1.2.8)
citeproc (1.0.3)
...

gem env gives:

RubyGems Environment:
  - RUBYGEMS VERSION: 2.6.2
  - RUBY VERSION: 2.3.1 (2016-04-26 patchlevel 112) [x86_64-darwin15]
  - INSTALLATION DIRECTORY: /usr/local/bin
  - USER INSTALLATION DIRECTORY: /Users/paulvickers/.gem/ruby/2.3.0
  - RUBY EXECUTABLE: /usr/local/opt/ruby/bin/ruby
  - EXECUTABLE DIRECTORY: /usr/local/bin/bin
  - SPEC CACHE DIRECTORY: /Users/paulvickers/.gem/specs
  - SYSTEM CONFIGURATION DIRECTORY: /usr/local/Cellar/ruby/2.3.1/etc
  - RUBYGEMS PLATFORMS:
    - ruby
    - x86_64-darwin-15
  - GEM PATHS:
     - /usr/local/bin
     - /Users/paulvickers/.gem/ruby/2.3.0
     - /usr/local/lib/ruby/gems/2.3.0
     - /usr/local/Cellar/ruby/2.3.1/lib/ruby/gems/2.3.0
  - GEM CONFIGURATION:
     - :update_sources => true
     - :verbose => true
     - :backtrace => false
     - :bulk_threshold => 1000
     - "gem" => "--no-document"
     - "install" => "--no-rdoc --no-ri"
  - REMOTE SOURCES:
     - https://rubygems.org/
  - SHELL PATH:
     - /usr/local/bin
     - /usr/bin
     - /bin
     - /usr/sbin
     - /sbin
     - /opt/X11/bin
     - /usr/local/git/bin
     - /Library/TeX/texbin

but which ruby gives /usr/local/bin/ruby

By the way, I should like to say thanks to Dan et al for this brilliant project. It has come on a long way in the last two years and it's exciting to see it develop so well.

[paulvickers]

Update:

I uninstalled and reinstalled asciidoctor-mathematical. Now I get a series of jruby failures, essentially failing to build the gem. Here's the output in a gist: https://gist.github.com/paulvickers/396d7ec9868e20e1d0dbaeef2a170e0b

[mojavelinux]

Indeed, you're not going to be able to use asciidoctor-mathematical from Gradle because mathematical uses a C extension (without a Java extension) and JRuby no longer supports C extensions. Creating a gem that uses a C extension without also providing a Java extension is considered to be bad practice. The only way to use asciidoctor-mathematical is to use the Asciidoctor via Ruby MRI (either via the asciidoctor command or the Ruby API).

[mojavelinux]

gem list reveals:

By default, the Gradle plugin (at least the latest snapshot) does not rely on the Ruby on your system. Instead, it uses JRuby in a self-contained environment within the build. The gems get downloaded and installed into the build directory and used from there.

[mojavelinux]

I should like to say thanks to Dan et al for this brilliant project. It has come on a long way in the last two years and it's exciting to see it develop so well.

Thanks! And thanks to the grassroots financial support, I'm able to continue working on it every single day (above and beyond contributions that come as part of working on contracts).

[mojavelinux]

To summarize, you did everything right to add a gem to the Ruby runtime. You just can't use gems that only have C extensions.

I recommend opening a ticket in mathematical to allow it to work in JRuby. I think it's very unfair to develop a gem that excludes the JRuby community.

[paulvickers]

Thanks. I've opened an issue over in mathematical.

[SRechenberger]

Is there any solution for this issue, yet?