class Prism::Translation::Parser

This class is the entry-point for converting a prism syntax tree into the whitequark/parser gem’s syntax tree. It inherits from the base parser for the parser gem, and overrides the parse* methods to parse with prism and then translate.

Public Instance Methods

default_encoding ()

The default encoding for Ruby files is UTF-8.

# File lib/prism/translation/parser.rb, line 41
def default_encoding
  Encoding::UTF_8
end

parse (source_buffer)

Parses a source buffer and returns the AST.

# File lib/prism/translation/parser.rb, line 49
def parse(source_buffer)
  @source_buffer = source_buffer
  source = source_buffer.source

  offset_cache = build_offset_cache(source)
  result = unwrap(Prism.parse(source, filepath: source_buffer.name, version: convert_for_prism(version), partial_script: true, encoding: false), offset_cache)

  build_ast(result.value, offset_cache)
ensure
  @source_buffer = nil
end

parse_with_comments (source_buffer)

Parses a source buffer and returns the AST and the source code comments.

# File lib/prism/translation/parser.rb, line 62
def parse_with_comments(source_buffer)
  @source_buffer = source_buffer
  source = source_buffer.source

  offset_cache = build_offset_cache(source)
  result = unwrap(Prism.parse(source, filepath: source_buffer.name, version: convert_for_prism(version), partial_script: true, encoding: false), offset_cache)

  [
    build_ast(result.value, offset_cache),
    build_comments(result.comments, offset_cache)
  ]
ensure
  @source_buffer = nil
end

tokenize (source_buffer, recover = false)

Parses a source buffer and returns the AST, the source code comments, and the tokens emitted by the lexer.

# File lib/prism/translation/parser.rb, line 79
def tokenize(source_buffer, recover = false)
  @source_buffer = source_buffer
  source = source_buffer.source

  offset_cache = build_offset_cache(source)
  result =
    begin
      unwrap(Prism.parse_lex(source, filepath: source_buffer.name, version: convert_for_prism(version), partial_script: true, encoding: false), offset_cache)
    rescue ::Parser::SyntaxError
      raise if !recover
    end

  program, tokens = result.value
  ast = build_ast(program, offset_cache) if result.success?

  [
    ast,
    build_comments(result.comments, offset_cache),
    build_tokens(tokens, offset_cache)
  ]
ensure
  @source_buffer = nil
end

try_declare_numparam (node)

Since prism resolves num params for us, we don’t need to support this kind of logic here.

# File lib/prism/translation/parser.rb, line 105
def try_declare_numparam(node)
  node.children[0].match?(/\A_[1-9]\z/)
end