Static analysis¶

Instances of Luoma::Template - as returned by Luoma::parse, Luoma::Environment#parse and Luoma::Environment#get_template - include methods for inspecting a template's variable, tag a filter usage, without rendering the template.

By default, all of the following methods with not attempt to load and analyze partial templates via {% include %}, {% render %} and {% import %}. Pass include_partials: true to analyze partial templates too.

See https://github.com/jg-rp/luoma-ruby/blob/main/lib/luoma/template.rb.

All variables¶

Template#variables returns an array of distinct, top-level variable names, without path segments. The resulting array will include variables that are local to the template, like those created with {% assign %}, or are in scope from {% for %} tags.

require "luoma"

template = Luoma.parse <<~SOURCE
  Hello, {{ you }}!
  {% assign x = 'foo' | upcase %}

  {% for ch in x %}
      - {{ ch }}
  {% endfor %}

  Goodbye, {{ you.first_name | capitalize }} {{ you.last_name }}
  Goodbye, {{ you.first_name }} {{ you.last_name }}`);
SOURCE

pp template.variables

Output

["you", "x", "ch"]

Paths¶

Template#variable_paths returns an array of variables including all path segments. The resulting array will include variables that are local to the template, like those created with {% assign %}, or are in scope from {% for %} tags.

# ... continued from above
pp template.variable_paths

Output

["you", "you.first_name", "you.last_name", "x", "ch"]

Segments¶

Template#variable_segments returns an array of variables as a nested array of segments. The resulting array will include variables that are local to the template, like those created with {% assign %}, or are in scope from {% for %} tags.

# ... continued from above
pp template.variable_segments

Output

[["you"], ["you", "first_name"], ["you", "last_name"], ["x"], ["ch"]]

Global variables¶

Template#global_variables returns an array of top-level variable names excluding local and block scoped names.

Notice that x and ch are excluded from this result compared to Template#variables above.

# ... continued from above
pp template.global_variables

Output

["you"]

Paths¶

Template#global_variable_paths returns an array global variables including path segments.

# ... continued from above
pp template.global_variable_paths

Output

["you", "you.first_name", "you.last_name"]

Segments¶

Template#global_variable_segments return an array global variables as nested arrays of segments.

# ... continued from above
pp template.global_variable_segments

Output

[["you"], ["you", "first_name"], ["you", "last_name"]]

Filter names¶

Template#filter_names returns an array of filter names that appear in the template.

# ... continued from above
pp template.filter_names

Output

["upcase", "capitalize"]

Tag names¶

Template#tag_names returns an array of tag names that appear in the template.

# ... continued from above
pp template.tag_names

Output

["assign", "for"]

Variable, tag and filter locations¶

Template#analyze returns an instance of Luoma::StaticAnalysis::Result containing all of the information provided by the other methods described on this page, plus the location (template name, span, line and column numbers) of every variable, tag and filter, each of which can appear many times across many templates.

Comments¶

Template#comments returns an array of Luoma::Comment instances with token and text attributes.

require "luoma"

template = Luoma.parse <<~SOURCE
  {##
   # some doc comment
   ##}

  Hello!

  {#
      some comment
  #}

  {% if false %}
    {# an inline comment #}
  {% endif %}
SOURCE

template.comments.each { |node| puts node.text.inspect }

Output

"\n # some doc comment\n "
"\n    some comment\n"
" an inline comment "