Class: JsxRosetta::Backend::ViewComponent::ExpressionTranslator

Inherits:
Object
  • Object
show all
Defined in:
lib/jsx_rosetta/backend/view_component/expression_translator.rb

Overview

Best-effort, narrowly-scoped JS-to-Ruby translation for the simple expression shapes that JSX components in real codebases use most often: bare identifiers, literals, simple member-expression chains (‘item.label`), and template literals composed of identifier interpolations. Anything more complex (function calls, conditionals, subscripts) returns `nil` from `#translate` so the backend can emit a TODO marker and fall back to the verbatim JS source.

Identifier resolution:

* Names in the active local scope (e.g. loop bindings) translate
  to the bare snake_case identifier.
* Names in `prop_names` translate to a `@snake_case` instance
  variable.
* Anything else translates to the bare snake_case identifier and
  is recorded as unresolved.

Local scopes can be pushed via ‘with_locals` and stack — each entry shadows lower entries.

Defined Under Namespace

Classes: Result

Constant Summary collapse

IDENTIFIER = 
/\A[a-zA-Z_$][a-zA-Z_$0-9]*\z/
STRING_LITERAL = 
/\A(['"])(.*)\1\z/m
NUMBER_LITERAL = 
/\A-?\d+(\.\d+)?\z/
TEMPLATE_LITERAL = 
/\A`(.*)`\z/m
TEMPLATE_INTERPOLATION = 
/\$\{([a-zA-Z_$][a-zA-Z_$0-9]*(?:\.[a-zA-Z_$][a-zA-Z_$0-9]*)*)\}/
MEMBER_CHAIN = 
/\A(?<root>[a-zA-Z_$][a-zA-Z_$0-9]*)(?<rest>(?:\.[a-zA-Z_$][a-zA-Z_$0-9]*)+)\z/
UNARY = 
/\A(?<op>!+|-|\+)(?<operand>.+)\z/m
SIMPLE_LITERALS = 
{ "null" => "nil", "undefined" => "nil", "true" => "true", "false" => "false" }.freeze

Instance Method Summary collapse

Constructor Details

#initialize(prop_names:) ⇒ ExpressionTranslator

Returns a new instance of ExpressionTranslator.



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# File 'lib/jsx_rosetta/backend/view_component/expression_translator.rb', line 38

def initialize(prop_names:)
  @prop_names = prop_names.to_set
  @local_stack = []
end

Instance Method Details

#translate(source) ⇒ Object 



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# File 'lib/jsx_rosetta/backend/view_component/expression_translator.rb', line 50

def translate(source)
  source = source.strip
  unresolved = []

  ruby = translate_ruby(source, unresolved)
  ruby && Result.new(ruby: ruby, unresolved_identifiers: unresolved.uniq)
end

#with_locals(names) ⇒ Object 



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# File 'lib/jsx_rosetta/backend/view_component/expression_translator.rb', line 43

def with_locals(names)
  @local_stack.push(names.compact)
  yield
ensure
  @local_stack.pop
end