Fails during generation with "undefined method `[]=' for #<OpenStruct>"

[hedgehog]

I've got asciidoctor-pdf crashing during generation. I've been able to reproduce using the following minimal test case. I've added the spine structure in response to asciidoctor/asciidoctor-epub3#7

Parent:

$ cat adoc/spine_bug.adoc
= Asciidoctor PDF: Sample Book
Author Name
v1.0, 2014-04-15

include::bug.adoc[]

Child:

$ cat adoc/bug.adoc
== Hello World

Full trace:

$ ruby -S asciidoctor-pdf --trace adoc/spine_bug.adoc
An exception occurred running /media/sf_host_docs/cubic/docs/data_dictionary/bin/asciidoctor-pdf:

undefined method `[]=' for #<OpenStruct> (NoMethodError)

Backtrace:

/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-pdf-1.5.0.alpha.6/lib/asciidoctor-pdf/theme_loader.rb:0:in `load'
/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-pdf-1.5.0.alpha.6/lib/asciidoctor-pdf/theme_loader.rb:36:in `load'
/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-pdf-1.5.0.alpha.6/lib/asciidoctor-pdf/theme_loader.rb:34:in `load'
/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-pdf-1.5.0.alpha.6/lib/asciidoctor-pdf/theme_loader.rb:30:in `load_file'
/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-pdf-1.5.0.alpha.6/lib/asciidoctor-pdf/theme_loader.rb:25:in `load_theme'
/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-pdf-1.5.0.alpha.6/lib/asciidoctor-pdf/converter.rb:149:in `init_pdf'
/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-pdf-1.5.0.alpha.6/lib/asciidoctor-pdf/converter.rb:90:in `convert_document'
/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-pdf-1.5.0.alpha.6/lib/asciidoctor-pdf/converter.rb:65:in `convert'
/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-1.5.2/lib/asciidoctor/document.rb:1028:in `convert'
/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-1.5.2/lib/asciidoctor.rb:1499:in `convert'
/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-1.5.2/lib/asciidoctor/cli/invoker.rb:94:in `invoke!'
/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-1.5.2/lib/asciidoctor/cli/invoker.rb:86:in `invoke!'
/home/hedge/.bundles/data_dictionary/rbx/2.1/gems/asciidoctor-pdf-1.5.0.alpha.6/bin/asciidoctor-pdf:13:in `__script__'
/media/sf_host_docs/cubic/docs/data_dictionary/bin/asciidoctor-pdf:16:in `__script__'
      OpenStruct#[]= (method_missing) at /home/hedge/.rubies/rbx-2.4.1/gems
                                         /gems/rubysl-ostruct-2.0.4/lib/rubysl
                                         /ostruct/ostruct.rb:196
 { } in Asciidoctor::Pdf::ThemeLoader#load at /home/hedge/.bundles
                                              /data_dictionary/rbx/2.1/gems
                                              /asciidoctor-pdf-1.5.0.alpha.6/lib
                                              /asciidoctor-pdf
                                              /theme_loader.rb+59
                             Hash#each at kernel/common/hash.rb:342
 { } in Asciidoctor::Pdf::ThemeLoader#load at /home/hedge/.bundles
                                              /data_dictionary/rbx/2.1/gems
                                              /asciidoctor-pdf-1.5.0.alpha.6/lib
                                              /asciidoctor-pdf
                                              /theme_loader.rb:36
        { } in Enumerable(Hash)#inject at kernel/common/enumerable.rb:317
                             Hash#each at kernel/common/hash.rb:342
               Enumerable(Hash)#inject at kernel/common/enumerable.rb:312
   Asciidoctor::Pdf::ThemeLoader#load at /home/hedge/.bundles/data_dictionary
                                         /rbx/2.1/gems
                                         /asciidoctor-pdf-1.5.0.alpha.6/lib
                                         /asciidoctor-pdf/theme_loader.rb:34
 Asciidoctor::Pdf::ThemeLoader.load_file at /home/hedge/.bundles
                                            /data_dictionary/rbx/2.1/gems
                                            /asciidoctor-pdf-1.5.0.alpha.6/lib
                                            /asciidoctor-pdf/theme_loader.rb:30
 Asciidoctor::Pdf::ThemeLoader.load_theme at /home/hedge/.bundles
                                             /data_dictionary/rbx/2.1/gems
                                             /asciidoctor-pdf-1.5.0.alpha.6/lib
                                             /asciidoctor-pdf/theme_loader.rb:25
 Asciidoctor::Pdf::Converter#init_pdf at /home/hedge/.bundles/data_dictionary
                                         /rbx/2.1/gems
                                         /asciidoctor-pdf-1.5.0.alpha.6/lib
                                         /asciidoctor-pdf/converter.rb:149
 Asciidoctor::Pdf::Converter#convert_document at /home/hedge/.bundles
                                                 /data_dictionary/rbx/2.1/gems
                                                 /asciidoctor-pdf-1.5.0.alpha.6
                                                 /lib/asciidoctor-pdf
                                                 /converter.rb:90
  Asciidoctor::Pdf::Converter#convert at /home/hedge/.bundles/data_dictionary
                                         /rbx/2.1/gems
                                         /asciidoctor-pdf-1.5.0.alpha.6/lib
                                         /asciidoctor-pdf/converter.rb:65
        Asciidoctor::Document#convert at /home/hedge/.bundles/data_dictionary
                                         /rbx/2.1/gems/asciidoctor-1.5.2/lib
                                         /asciidoctor/document.rb:1028
                  Asciidoctor.convert at /home/hedge/.bundles/data_dictionary
                                         /rbx/2.1/gems/asciidoctor-1.5.2/lib
                                         /asciidoctor.rb:1499
 { } in Asciidoctor::Cli::Invoker#invoke! at /home/hedge/.bundles
                                             /data_dictionary/rbx/2.1/gems
                                             /asciidoctor-1.5.2/lib/asciidoctor
                                             /cli/invoker.rb:94
                            Array#each at kernel/bootstrap/array.rb:76
    Asciidoctor::Cli::Invoker#invoke! at /home/hedge/.bundles/data_dictionary
                                         /rbx/2.1/gems/asciidoctor-1.5.2/lib
                                         /asciidoctor/cli/invoker.rb:86
                    Object#__script__ at /home/hedge/.bundles/data_dictionary
                                         /rbx/2.1/gems
                                         /asciidoctor-pdf-1.5.0.alpha.6/bin
                                         /asciidoctor-pdf:13
                   Kernel(Object)#load at kernel/common/kernel.rb:497
                     Object#__script__ at bin/asciidoctor-pdf:16
      Rubinius::CodeLoader#load_script at kernel/delta/code_loader.rb:66
      Rubinius::CodeLoader.load_script at kernel/delta/code_loader.rb:152
               Rubinius::Loader#script at kernel/loader.rb:645
                 Rubinius::Loader#main at kernel/loader.rb:799
direnv: loading ~/.direnvrc
direnv: loading .envrc
direnv: using ruby
direnv: export ~PATH

[mojavelinux]

Asciidoctor PDF is not known to work with Rubinius and is not tested. Before we start playing whack-a-mole trying to sort out the root cause of this error, we need to get a proper test suite setup (#37). Then, we can run the tests on all the Ruby versions like we do with Asciidoctor core and be confident we aren't breaking things :)

When I try to run Asciidoctor PDF with Rubinius, I get a different error ("OpenURI is not a module, but a Autoload"), so I'm not able to debug this specific issue yet.

[mojavelinux]

Btw, thanks for reporting!