Invalid scheme format: '; dark' in /usr/src/app/_layouts/default.html

[vincerubinetti]

Origination: greenelab/greenelab.com#139

Full error:

 Liquid Exception: Invalid scheme format: '; dark' in /usr/src/app/_layouts/default.html
bundler: failed to load command: jekyll (/usr/local/bundle/bin/jekyll)
/usr/local/bundle/gems/addressable-2.8.1/lib/addressable/uri.rb:917:in `scheme=': Invalid scheme format: '; dark' (Addressable::URI::InvalidURIError)
        from /usr/local/bundle/gems/addressable-2.8.1/lib/addressable/uri.rb:842:in `block in initialize'
        from /usr/local/bundle/gems/addressable-2.8.1/lib/addressable/uri.rb:2408:in `defer_validation'
        from /usr/local/bundle/gems/addressable-2.8.1/lib/addressable/uri.rb:839:in `initialize'
        from /usr/local/bundle/gems/addressable-2.8.1/lib/addressable/uri.rb:152:in `new'
        from /usr/local/bundle/gems/addressable-2.8.1/lib/addressable/uri.rb:152:in `parse'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/filters/url_filters.rb:75:in `compute_relative_url'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/filters/url_filters.rb:40:in `relative_url'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/strainer.rb:56:in `invoke'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/context.rb:86:in `invoke'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/variable.rb:84:in `block in render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/variable.rb:82:in `each'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/variable.rb:82:in `inject'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/variable.rb:82:in `render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/block_body.rb:103:in `render_node_to_output'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/block_body.rb:80:in `render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/tags/if.rb:46:in `block (2 levels) in render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/tags/if.rb:44:in `each'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/tags/if.rb:44:in `block in render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/context.rb:123:in `stack'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/tags/if.rb:43:in `render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/block_body.rb:103:in `render_node_to_output'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/block_body.rb:82:in `render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/tags/for.rb:160:in `block (2 levels) in render_segment'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/tags/for.rb:158:in `each'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/tags/for.rb:158:in `block in render_segment'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/context.rb:123:in `stack'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/tags/for.rb:150:in `render_segment'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/tags/for.rb:79:in `render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/block_body.rb:103:in `render_node_to_output'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/block_body.rb:82:in `render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/template.rb:206:in `block in render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/template.rb:240:in `with_profiling'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/template.rb:205:in `render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/template.rb:218:in `render!'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:39:in `block (3 levels) in render!'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:59:in `measure_counts'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:38:in `block (2 levels) in render!'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:63:in `measure_bytes'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:37:in `block in render!'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:70:in `measure_time'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:36:in `render!'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/inclusion.rb:16:in `render'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/tags/include.rb:208:in `block in render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/context.rb:123:in `stack'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/tags/include.rb:206:in `render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/block_body.rb:103:in `render_node_to_output'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/block_body.rb:91:in `render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/template.rb:206:in `block in render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/template.rb:240:in `with_profiling'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/template.rb:205:in `render'
        from /usr/local/bundle/gems/liquid-4.0.4/lib/liquid/template.rb:218:in `render!'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:39:in `block (3 levels) in render!'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:59:in `measure_counts'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:38:in `block (2 levels) in render!'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:63:in `measure_bytes'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:37:in `block in render!'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:70:in `measure_time'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/liquid_renderer/file.rb:36:in `render!'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/renderer.rb:129:in `render_liquid'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/renderer.rb:192:in `render_layout'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/renderer.rb:161:in `place_in_layouts'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/renderer.rb:93:in `render_document'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/renderer.rb:63:in `run'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/site.rb:572:in `render_regenerated'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/site.rb:564:in `block in render_pages'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/site.rb:563:in `each'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/site.rb:563:in `render_pages'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/site.rb:211:in `render'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/site.rb:80:in `process'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/command.rb:28:in `process_site'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/commands/build.rb:65:in `build'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/commands/build.rb:36:in `process'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/command.rb:91:in `block in process_with_graceful_fail'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/command.rb:91:in `each'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/command.rb:91:in `process_with_graceful_fail'
        from /usr/local/bundle/gems/jekyll-4.3.2/lib/jekyll/commands/serve.rb:86:in `block (2 levels) in init_with_program'
        from /usr/local/bundle/gems/mercenary-0.4.0/lib/mercenary/command.rb:221:in `block in execute'
        from /usr/local/bundle/gems/mercenary-0.4.0/lib/mercenary/command.rb:221:in `each'
        from /usr/local/bundle/gems/mercenary-0.4.0/lib/mercenary/command.rb:221:in `execute'
        from /usr/local/bundle/gems/mercenary-0.4.0/lib/mercenary/program.rb:44:in `go'
        from /usr/local/bundle/gems/mercenary-0.4.0/lib/mercenary.rb:21:in `program'
        from /usr/local/bundle/gems/jekyll-4.3.2/exe/jekyll:15:in `<top (required)>'
        from /usr/local/bundle/bin/jekyll:25:in `load'
        from /usr/local/bundle/bin/jekyll:25:in `<top (required)>'
        from /usr/local/bundle/gems/bundler-2.5.6/lib/bundler/cli/exec.rb:58:in `load'
        from /usr/local/bundle/gems/bundler-2.5.6/lib/bundler/cli/exec.rb:58:in `kernel_load'
        from /usr/local/bundle/gems/bundler-2.5.6/lib/bundler/cli/exec.rb:23:in `run'
        from /usr/local/bundle/gems/bundler-2.5.6/lib/bundler/cli.rb:451:in `exec'
        from /usr/local/bundle/gems/bundler-2.5.6/lib/bundler/vendor/thor/lib/thor/command.rb:28:in `run'
        from /usr/local/bundle/gems/bundler-2.5.6/lib/bundler/vendor/thor/lib/thor/invocation.rb:127:in `invoke_command'
        from /usr/local/bundle/gems/bundler-2.5.6/lib/bundler/vendor/thor/lib/thor.rb:527:in `dispatch'
        from /usr/local/bundle/gems/bundler-2.5.6/lib/bundler/cli.rb:34:in `dispatch'
        from /usr/local/bundle/gems/bundler-2.5.6/lib/bundler/vendor/thor/lib/thor/base.rb:584:in `start'
        from /usr/local/bundle/gems/bundler-2.5.6/lib/bundler/cli.rb:28:in `start'
        from /usr/local/bundle/gems/bundler-2.5.6/exe/bundle:28:in `block in <top (required)>'
        from /usr/local/bundle/gems/bundler-2.5.6/lib/bundler/friendly_errors.rb:117:in `with_friendly_errors'
        from /usr/local/bundle/gems/bundler-2.5.6/exe/bundle:20:in `<top (required)>'
        from /usr/local/bundle/bin/bundle:25:in `load'
        from /usr/local/bundle/bin/bundle:25:in `<main>'

Starting from the current template version, to replicate this bug, add a section break component to a blog post, and remove any section breaks in the main blog/index.md page.

Then, from that starting point, do any one of the following to make the bug go away again:

• Remove section from blog post
• Add section to main blog page
• Remove section from blog post and main blog page
• Remove content=d.content from list.html
• Remove data-search="{{ search }}" from post-excerpt.html
• Use single post-excerpt.html on main blog page (with lookup param) instead of list component
• Remove relative_url from style="--image: url('{{ image | relative_url | uri_escape }}')" in content.html

Consolidation/summary of the first three bullets: this bug only happens when section is not in main blog page, and is in blog post. The other 3 permutations of these two booleans are fine.

What appears to be happening is related to the section.html component and the non-conventional (by necessity) way that content.html captures the section component parameters.

The fix for this is probably replacing the e.g. "dark: (.*);" regexes in content.html with "dark: (.*?);", because it seems like the capture group is greedily matching too far, i.e. background: some-imageˇ; dark: true; size: pageˇ; (from ˇ to ˇ).

What I still don't understand, or just can't wrap my head around in my current mental state, is why I've never run into this before, and why the particular solutions bulleted above make the problem go away. This makes me uneasy that a "fix" for this won't be a true fix: some edge cases will remain error-prone, or something else new will break as a result.