Class: LcpRuby::Generators::Entity::FieldTokenParser

Inherits:
Object
  • Object
show all
Defined in:
lib/generators/lcp_ruby/entity/field_token_parser.rb

Constant Summary collapse

TOKEN_RE = 
/\A
  (?<name>[a-z_][a-z0-9_]*)
  :
  (?<type>[a-z_]+)
  (?:\{(?<enum_values>[^}]*\|[^}]*)\})?
  (?<required>!)?
  (?<flags>(?::[a-z_]+)*)
  (?<blocks>(?:\{[^}]*\})*)
\z/x
NUMERIC_OPTION_KEYS =

Numeric option keys whose value the parser coerces to Integer at parse time so downstream emitters don’t have to. Only ‘:limit` (v3 string limit) is wired into the emitter today; `:precision` and `:scale` are deferred to v4 per Decision 26 (the brace-modifier grammar has no two-arg form for `decimalN,M`).

%i[limit].freeze

Class Method Summary collapse

Class Method Details

.block_flag_order_hint(raw) ⇒ Object 



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# File 'lib/generators/lcp_ruby/entity/field_token_parser.rb', line 91

def self.block_flag_order_hint(raw)
  return nil unless (m = BLOCK_FLAG_ORDER_RE.match(raw))
  block = "{#{m[:block]}}"
  flag  = ":#{m[:flag]}"
  "expected ':flags' before '{blocks}' — got '#{block}' followed by '#{flag}'. " \
    "Reorder to '#{flag}#{block}' or split into separate tokens."
end

.parse(tokens) ⇒ Object 



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# File 'lib/generators/lcp_ruby/entity/field_token_parser.rb', line 27

def self.parse(tokens)
  tokens.map { |t| parse_token(t) }
end

.parse_error_for(raw) ⇒ Object 



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# File 'lib/generators/lcp_ruby/entity/field_token_parser.rb', line 76

def self.parse_error_for(raw)
  base = "Cannot parse field token '#{raw}'. " \
         "Expected name:type[{values}][!][:flags][{blocks}]."
  hint = block_flag_order_hint(raw)
  hint ? "#{base}\n  #{hint}" : base
end

.parse_token(raw) ⇒ Object 



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# File 'lib/generators/lcp_ruby/entity/field_token_parser.rb', line 31

def self.parse_token(raw)
  m = TOKEN_RE.match(raw) or raise Thor::Error, parse_error_for(raw)

  name = m[:name].to_sym
  type = m[:type].to_sym
  modifiers = {}
  options = {}

  enum_values =
    if m[:enum_values]
      raise Thor::Error,
        "Pipe-separated value list is only valid for enum fields (got '#{raw}')." unless type == :enum
      m[:enum_values].split("|").map(&:strip)
    elsif type == :enum
      raise Thor::Error,
        "Enum field '#{name}' requires inline values: #{name}:enum{val1|val2|val3}"
    end

  modifiers[:required] = true if m[:required]

  m[:flags].to_s.scan(/:([a-z_]+)/).each { |(flag)| modifiers[flag.to_sym] = true }

  m[:blocks].to_s.scan(/\{([^}]*)\}/).each do |(body)|
    body.split(",").map(&:strip).each do |segment|
      raise Thor::Error, "Empty modifier in '#{raw}'." if segment.empty?

      if segment.include?(":")
        key, value = segment.split(":", 2).map(&:strip)
        key_sym = key.to_sym
        options[key_sym] = NUMERIC_OPTION_KEYS.include?(key_sym) ? value.to_i : value
      else
        modifiers[segment.to_sym] = true
      end
    end
  end

  FieldDescriptor.new(
    name: name,
    type: type,
    enum_values: enum_values,
    modifiers: modifiers,
    options: options
  )
end