- nil is NOT empty (but IS blank) - matches Shopify production
- String first/last returns '' for empty strings, not nil - matches ActiveSupport
- Add test for nil not being empty
- Add liquid-spec gem from GitHub to :spec group
- Create spec/ruby-liquid.rb adapter for the reference implementation
- Add spec job to CI workflow to run liquid-spec tests
Implement ActiveSupport-compatible behaviors internally so Liquid works
correctly without ActiveSupport being loaded:
1. String first/last via property access (name.first, name.last)
- VariableLookup now handles string[0] and string[-1] for first/last
2. String first/last via filters (name | first, name | last)
- StandardFilters#first and #last now handle strings
3. blank?/empty? comparisons for types without these methods
- Condition now implements liquid_blank? and liquid_empty? internally
- blank? matches ActiveSupport: nil, false, empty/whitespace strings,
empty arrays/hashes are all blank
- empty? checks length == 0 only (whitespace is NOT empty)
This fixes spec failures for templates like:
- {{ name.first }} / {{ name | first }} on strings
- {% if x == blank %} for whitespace strings, empty hashes/arrays
- {% case ' ' %}{% when blank %} matching whitespace