Class: Hocon::Impl::Parser::ParseContext

Inherits:
Object
  • Object
show all
Defined in:
lib/hocon/impl/parser.rb

Defined Under Namespace

Classes: Element

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(flavor, origin, tokens, includer, include_context) ⇒ ParseContext

Returns a new instance of ParseContext.



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# File 'lib/hocon/impl/parser.rb', line 136

def initialize(flavor, origin, tokens, includer, include_context)
  @line_number = 1
  @flavor = flavor
  @base_origin = origin
  @buffer = []
  @tokens = tokens
  @includer = includer
  @include_context = include_context
  @path_stack = []
  # this is the number of "equals" we are inside,
  # used to modify the error message to reflect that
  # someone may think this is .properties format.
  @equals_count = 0
end

Class Method Details

.attracts_leading_comments?(token) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/hocon/impl/parser.rb', line 121

def self.attracts_leading_comments?(token)
  # a comment just before a close } generally doesn't go with the
  # value before it, unless it's on the same line as that value
  !(Tokens.newline?(token) ||
      token == Tokens::START ||
      token == Tokens::CLOSE_CURLY ||
      token == Tokens::CLOSE_SQUARE ||
      token == Tokens::EOF)
end

.attracts_trailing_comments?(token) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/hocon/impl/parser.rb', line 110

def self.attracts_trailing_comments?(token)
  # EOF can't have a trailing comment; START, OPEN_CURLY, and
  # OPEN_SQUARE followed by a comment should behave as if the comment
  # went with the following field or element. Associating a comment
  # with a newline would mess up all the logic for comment tracking,
  # so don't do that either.
  !(Tokens.newline?(token) ||
    token == Tokens::START ||
    token == Tokens::OPEN_CURLY)
end

.include_keyword?(token) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/hocon/impl/parser.rb', line 131

def self.include_keyword?(token)
  Tokens.unquoted_text?(token) &&
      (Tokens.unquoted_text(token) == "include")
end

Instance Method Details

#add_any_comments_after_any_comma(v) ⇒ Object



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# File 'lib/hocon/impl/parser.rb', line 652

def add_any_comments_after_any_comma(v)
  t = next_token  # do NOT skip newlines, we only
                  # want same-line comments
  if t.token == Tokens::COMMA
    # steal the comments from after the comma
    put_back(t.remove_all)
    v.with_origin(t.append_comments(v.origin))
  else
    put_back(t)
    v
  end
end

#add_key_name(message) ⇒ Object



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# File 'lib/hocon/impl/parser.rb', line 716

def add_key_name(message)
  prev_field_name = previous_field_name
  if !prev_field_name.nil?
    "in value for key '#{prev_field_name}': #{message}"
  else
    message
  end
end

#add_quote_suggestion(bad_token, message, last_path = nil, inside_equals = (@equals_count > 0)) ⇒ Object



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# File 'lib/hocon/impl/parser.rb', line 725

def add_quote_suggestion(bad_token, message, last_path = nil, inside_equals = (@equals_count > 0))
  prev_field_name = previous_field_name(last_path)
  part =
      if bad_token == Tokens::EOF.to_s
        # EOF requires special handling for the error to make sense.
        if !prev_field_name.nil?
          "#{message} (if you intended '#{prev_field_name}' " +
          "to be part of a value, instead of a key, " +
          "try adding double quotes around the whole value"
        else
          message
        end
      else
        if !prev_field_name.nil?
          "#{message} (if you intended #{bad_token} " +
          "to be part of the value for '#{prev_field_name}', " +
          "try enclosing the value in double quotes"
        else
          "#{message} (if you intended #{bad_token} " +
          "to be part of a key or string value, " +
          "try enclosing the key or value in double quotes"
        end
      end

  if inside_equals
    "#{part}, or you may be able to rename the file .properties rather than .conf)"
  else
    "#{part})"
  end
end

#check_element_separatorObject

In arrays and objects, comma can be omitted as long as there’s at least one newline instead. this skips any newlines in front of a comma, skips the comma, and returns true if it found either a newline or a comma. The iterator is left just after the comma or the newline.



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# File 'lib/hocon/impl/parser.rb', line 671

def check_element_separator
  if @flavor == ConfigSyntax::JSON
    t = next_token_ignoring_newline
    if (t.token == Tokens::COMMA)
      true
    else
      put_back(t)
      false
    end
  else
    saw_separator_or_newline = false
    t = next_token
    while true
      if Tokens.newline?(t.token)
        # newline number is the line just ended, so add one
        @line_number = t.token.line_number + 1
        saw_separator_or_newline = true

        # we want to continue to also eat a comma if there is one
      elsif t.token == Tokens::COMMA
        return true
      else
        # non-newline-or-comma
        put_back(t)
        return saw_separator_or_newline
      end
      t = next_token
    end
  end
end

#consolidate_comment_block(comment_token) ⇒ Object



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# File 'lib/hocon/impl/parser.rb', line 159

def consolidate_comment_block(comment_token)
  # a comment block "goes with" the following token
  # unless it's separated from it by a blank line.
  # we want to build a list of newline tokens followed
  # by a non-newline non-comment token; with all comments
  # associated with that final non-newline non-comment token.
  # a comment AFTER a token, without an intervening newline,
  # also goes with that token, but isn't handled in this method,
  # instead we handle it later by peeking ahead.
  new_lines = []
  comments = []

  previous_token = nil
  next_token = comment_token
  while true
    if Tokens.newline?(next_token)
      if (previous_token != nil) && Tokens.newline?(previous_token)
        # blank line; drop all comments to this point and
        # start a new comment block
        comments.clear
      end
      new_lines.push(next_token)
    elsif Tokens.comment?(next_token)
      comments.push(next_token)
    else
      # a non-newline non-comment token

      # comments before a close brace or bracket just get dumped
      unless self.class.attracts_leading_comments?(next_token)
        comments.clear
      end
      break
    end

    previous_token = next_token
    next_token = @tokens.next
  end

  # put our concluding token in the queue with all the comments
  # attached
  @buffer.push(TokenWithComments.new(next_token, comments))

  # now put all the newlines back in front of it
  new_lines.reverse.each do |nl|
    @buffer.push(TokenWithComments.new(nl))
  end
end

#consolidate_value_tokensObject

merge a bunch of adjacent values into one value; change unquoted text into a string value.



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# File 'lib/hocon/impl/parser.rb', line 210

def consolidate_value_tokens
  # this trick is not done in JSON
  return if @flavor == ConfigSyntax::JSON

  # create only if we have value tokens
  values = nil

  # ignore a newline up front
  t = next_token_ignoring_newline
  while true
    v = nil
    if (Tokens.value?(t.token)) || (Tokens.unquoted_text?(t.token)) ||
        (Tokens.substitution?(t.token)) || (t.token == Tokens::OPEN_CURLY) ||
        (t.token == Tokens::OPEN_SQUARE)
      # there may be newlines _within_ the objects and arrays
      v = parse_value(t)
    else
      break
    end

    if v.nil?
      raise ConfigBugError("no value")
    end

    if values.nil?
      values = []
    end
    values.push(v)

    t = next_token # but don't consolidate across a newline
  end
  # the last one wasn't a value token
  put_back(t)

  return if values.nil?

  consolidated = ConfigConcatenation.concatenate(values)

  put_back(TokenWithComments.new(Tokens.new_value(consolidated)))
end

#create_value_under_path(path, value) ⇒ Object



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# File 'lib/hocon/impl/parser.rb', line 280

def create_value_under_path(path, value)
  # for path foo.bar, we are creating
  # { "foo" : { "bar" : value } }
  keys = []

  key = path.first
  remaining = path.remainder
  while !key.nil?
    # for ruby: convert string keys to symbols
    if key.is_a?(String)
      key = key
    end
    keys.push(key)
    if remaining.nil?
      break
    else
      key = remaining.first
      remaining = remaining.remainder
    end
  end

  # the setComments(null) is to ensure comments are only
  # on the exact leaf node they apply to.
  # a comment before "foo.bar" applies to the full setting
  # "foo.bar" not also to "foo"
  keys = keys.reverse
  # this is just a ruby means for doing first/rest
  deepest, *rest = *keys
  o = SimpleConfigObject.new(value.origin.set_comments(nil),
                             {deepest => value})
  while !rest.empty?
    deepest, *rest = *rest
    o = SimpleConfigObject.new(value.origin.set_comments(nil),
                               {deepest => o})
  end

  o
end

#key_value_separator_token?(t) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/hocon/impl/parser.rb', line 151

def key_value_separator_token?(t)
  if @flavor == ConfigSyntax::JSON
    t == Tokens::COLON
  else
    [Tokens::COLON, Tokens::EQUALS, Tokens::PLUS_EQUALS].any? { |sep| sep == t }
  end
end

#line_originObject



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# File 'lib/hocon/impl/parser.rb', line 251

def line_origin
  @base_origin.set_line_number(@line_number)
end

#next_tokenObject



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# File 'lib/hocon/impl/parser.rb', line 624

def next_token
  with_comments = pop_token
  t = with_comments.token

  if Tokens.problem?(t)
    origin = t.origin
    message = Tokens.get_problem_message(t)
    cause = Tokens.get_problem_cause(t)
    suggest_quotes = Tokens.get_problem_suggest_quotes(t)
    if suggest_quotes
      message = add_quote_suggestion(t.to_s, message)
    else
      message = add_key_name(message)
    end
    raise ConfigParseError.new(origin, message, cause)
  else
    if @syntax == ConfigSyntax::JSON
      if Tokens.unquoted_text?(t)
        raise parse_error(add_key_name("Token not allowed in valid JSON: '#{Tokens.get_unquoted_text(t)}'"))
      elsif Tokens.substitution?(t)
        raise parse_error(add_key_name("Substitutions (${} syntax) not allowed in JSON"))
      end
    end

    with_comments
  end
end

#next_token_ignoring_newlineObject



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# File 'lib/hocon/impl/parser.rb', line 603

def next_token_ignoring_newline
  t = next_token
  while Tokens.newline?(t.token)
    # line number tokens have the line that was _ended_ by the
    # newline, so we have to add one. We have to update lineNumber
    # here and also below, because not all tokens store a line
    # number, but newline tokens always do.
    @line_number = t.token.line_number + 1

    t = next_token
  end

  # update line number again, iff we have one
  new_number = t.token.line_number
  if new_number >= 0
    @line_number = new_number
  end

  t
end

#parseObject



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# File 'lib/hocon/impl/parser.rb', line 558

def parse
  t = next_token_ignoring_newline
  if t.token != Tokens::START
    raise ConfigBugError, "token stream did not begin with START, had #{t}"
  end

  t = next_token_ignoring_newline
  result = nil
  if (t.token == Tokens::OPEN_CURLY) or
      (t.token == Tokens::OPEN_SQUARE)
    result = parse_value(t)
  else
    if @syntax == ConfigSyntax::JSON
      if t.token == Tokens::END
        raise parse_error("Empty document")
      else
        raise parse_error("Document must have an object or array at root, unexpected token: #{t}")
      end
    else
      ## the root object can omit the surrounding braces.
      ## this token should be the first field's key, or part
      ## of it, so put it back.
      put_back(t)
      result = parse_object(false)
      ## in this case we don't try to use commentsStack comments
      ## since they would all presumably apply to fields not the
      ## root object
    end
  end

  t = next_token_ignoring_newline
  if t.token == Tokens::EOF
    result
  else
    raise parse_error("Document has trailing tokens after first object or array: #{t}")
  end
end

#parse_arrayObject



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# File 'lib/hocon/impl/parser.rb', line 498

def parse_array
  # invoked just after the OPEN_SQUARE
  array_origin = line_origin
  values = []

  consolidate_value_tokens

  t = next_token_ignoring_newline

  # special-case the first element
  if t.token == Tokens::CLOSE_SQUARE
    return SimpleConfigList.new(t.append_comments(array_origin), [])
  elsif (Tokens.value?(t.token)) ||
      (t.token == Tokens::OPEN_CURLY) ||
      (t.token == Tokens::OPEN_SQUARE)
    v = parse_value(t)
    v = add_any_comments_after_any_comma(v)
    values.push(v)
  else
    raise parse_error(add_key_name("List should have ] or a first element after the open [, instead had token: " +
      "#{t} (if you want #{t} to be part of a string value, then double-quote it)"))
  end

  # now remaining elements
  while true
    # just after a value
    if check_element_separator
      # comma (or newline equivalent) consumed
    else
      t = next_token_ignoring_newline
      if t.token == Tokens::CLOSE_SQUARE
        return SimpleConfigList.new(t.append_comments(array_origin), values)
      else
        raise parse_error(add_key_name("List should have ended with ] or had a comma, instead had token: " +
          "#{t} (if you want #{t} to be part of a string value, then double-quote it)"))
      end
    end

    # now just after a comma
    consolidate_value_tokens

    t = next_token_ignoring_newline

    if (Tokens.value?(t.token)) ||
        (t.token == Tokens::OPEN_CURLY) ||
        (t.token == Tokens::OPEN_SQUARE)
      v = parse_value(t)
      v = add_any_comments_after_any_comma(v)
      values.push(v)
    elsif (@flavor != ConfigSyntax::JSON) &&
            (t.token == Tokens::CLOSE_SQUARE)
      # we allow one trailing comma
      put_back(t)
    else
      raise parse_error(add_key_name("List should have had new element after a comma, instead had token: " +
      "#{t} (if you want the comma or #{t} to be part of a string value, then double-quote it)"))
    end
  end
end

#parse_error(message, cause = nil) ⇒ Object



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# File 'lib/hocon/impl/parser.rb', line 702

def parse_error(message, cause = nil)
  ConfigParseError.new(line_origin, message, cause)
end

#parse_key(token) ⇒ Object



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# File 'lib/hocon/impl/parser.rb', line 319

def parse_key(token)
  if @flavor == ConfigSyntax::JSON
    if Tokens.value_with_type?(token.token, ConfigValueType::STRING)
      key = Tokens.value(token.token).unwrapped
      Path.new_key(key)
    else
      raise parse_error(add_key_name("Expecting close brace } or a field name here, got #{token}"))
    end
  else
    expression = []
    t = token
    while Tokens.value?(t.token) || Tokens.unquoted_text?(t.token)
      expression.push(t.token)
      t = next_token # note: don't cross a newline
    end

    if expression.empty?
      raise parse_error(add_key_name("expecting a close brace or a field name here, got #{t}"))
    end

    put_back(t)
    Hocon::Impl::Parser.parse_path_expression(expression, line_origin)
  end
end

#parse_object(had_open_curly) ⇒ Object



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# File 'lib/hocon/impl/parser.rb', line 344

def parse_object(had_open_curly)
  # invoked just after the OPEN_CURLY (or START, if !hadOpenCurly)
  values = {}
  object_origin = line_origin
  after_comma = false
  last_path = nil
  last_inside_equals = false

  while true
    t = next_token_ignoring_newline
    if t.token == Tokens::CLOSE_CURLY
      if (@flavor == ConfigSyntax::JSON) && after_comma
        raise parse_error(
                  add_quote_suggestion(t,
                    "unbalanced close brace '}' with no open brace"))
      end

      object_origin = t.append_comments(object_origin)
      break
    elsif (t.token == Tokens::EOF) && !had_open_curly
      put_back(t)
      break
    elsif (@flavor != ConfigSyntax::JSON) &&
        self.class.include_keyword?(t.token)
      parse_include(values)
      after_comma = false
    else
      key_token = t
      path = parse_key(key_token)
      after_key = next_token_ignoring_newline
      inside_equals = false

      # path must be on-stack while we parse the value
      @path_stack.push(path)
      value_token = nil
      new_value = nil
      if (@flavor == ConfigSyntax::CONF) &&
          (after_key.token == Tokens::OPEN_CURLY)
        # can omit the ':' or '=' before an object value
        value_token = after_key
      else
        if !key_value_separator_token?(after_key.token)
          raise parse_error(
                    add_quote_suggestion(after_key,
                      "Key '#{path.render}' may not be followed by token: #{after_key}"))
        end

        if after_key.token == Tokens::EQUALS
          inside_equals = true
          @equals_count += 1
        end

        consolidate_value_tokens
        value_token = next_token_ignoring_newline

        # put comments from separator token on the value token
        value_token = value_token.prepend(after_key.comments)
      end

      # comments from the key token go to the value token
      new_value = parse_value(value_token.prepend(key_token.comments))

      if after_key.token == Tokens::PLUS_EQUALS
        previous_ref = ConfigReference.new(
            new_value.origin,
            SubstitutionExpression.new(full_current_path, true))
        list = SimpleConfigList.new(new_value.origin, [new_value])
        new_value = ConfigConcatenation.concatenate([previous_ref, list])
      end

      new_value = add_any_comments_after_any_comma(new_value)

      last_path = @path_stack.pop
      if inside_equals
        @equals_count -= 1
      end
      last_inside_equals = inside_equals

      key = path.first

      # for ruby: convert string keys to symbols
      if key.is_a?(String)
        key = key
      end

      remaining = path.remainder

      if !remaining
        existing = values[key]
        if existing
          # In strict JSON, dups should be an error; while in
          # our custom config language, they should be merged
          # if the value is an object (or substitution that
          # could become an object).

          if @flavor == ConfigSyntax::JSON
            raise parse_error("JSON does not allow duplicate fields: '#{key}'" +
                                  " was already seen at #{existing.origin().description()}")
          else
            new_value = new_value.with_fallback(existing)
          end
        end
        values[key] = new_value
      else
        if @flavor == ConfigSyntax::JSON
          raise ConfigBugError, "somehow got multi-element path in JSON mode"
        end

        obj = create_value_under_path(remaining, new_value)
        existing = values[key]
        if !existing.nil?
          obj = obj.with_fallback(existing)
        end
        values[key] = obj
      end

      after_comma = false
    end

    if check_element_separator
      # continue looping
      after_comma = true
    else
      t = next_token_ignoring_newline
      if t.token == Tokens::CLOSE_CURLY
        if !had_open_curly
          raise parse_error(
                    add_quote_suggestion(last_path, last_inside_equals,
                                         t, "unbalanced close brace '}' with no open brace"))
        end

        object_origin = t.append_comments(object_origin)
        break
      elsif had_open_curly
        raise parse_error(
                  add_quote_suggestion(t, "Expecting close brace } or a comma, got #{t}",
                                       last_path, last_inside_equals))
      else
        if t.token == Tokens::END
          put_back(t)
          break
        else
          raise parse_error(
                    add_quote_suggestion(t, "Expecting end of input or a comma, got #{t}",
                                         last_path, last_inside_equals))
        end
      end
    end
  end

  SimpleConfigObject.new(object_origin, values)

end

#parse_value(t) ⇒ Object



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# File 'lib/hocon/impl/parser.rb', line 255

def parse_value(t)
  v = nil

  if Tokens.value?(t.token)
    # if we consolidateValueTokens() multiple times then
    # this value could be a concatenation, object, array,
    # or substitution already.
    v = Tokens.value(t.token)
  elsif Tokens.unquoted_text?(t.token)
    v = Hocon::Impl::ConfigString.new(t.token.origin, Tokens.unquoted_text(t.token))
  elsif Tokens.substitution?(t.token)
    v = ConfigReference.new(t.token.origin, token_to_substitution_expression(t.token))
  elsif t.token == Tokens::OPEN_CURLY
    v = parse_object(true)
  elsif t.token == Tokens::OPEN_SQUARE
    v = parse_array
  else
    raise parse_error(
              add_quote_suggestion(t.token.to_s,
                "Expecting a value but got wrong token: #{t.token}"))
  end

  v.with_origin(t.prepend_comments(v.origin))
end

#pop_tokenObject



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# File 'lib/hocon/impl/parser.rb', line 757

def pop_token
  with_preceding_comments = pop_token_without_trailing_comment
  # handle a comment AFTER the other token,
  # but before a newline. If the next token is not
  # a comment, then any comment later on the line is irrelevant
  # since it would end up going with that later token, not
  # this token. Comments are supposed to be processed prior
  # to adding stuff to the buffer, so they can only be found
  # in "tokens" not in "buffer" in theory.
  if !self.class.attracts_trailing_comments?(with_preceding_comments.token)
    with_preceding_comments
  elsif @buffer.empty?
    after = @tokens.next
    if Tokens.comment?(after)
      with_preceding_comments.add(after)
    else
      @buffer << TokenWithComments.new(after)
      with_preceding_comments
    end
  else
    # comments are supposed to get attached to a token,
    # not put back in the buffer. Assert this as an invariant.
    if Tokens.comment?(@buffer.last.token)
      raise ConfigBugError, "comment token should not have been in buffer: #{@buffer}"
    end
    with_preceding_comments
  end
end

#pop_token_without_trailing_commentObject



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# File 'lib/hocon/impl/parser.rb', line 786

def pop_token_without_trailing_comment
  if @buffer.empty?
    t = @tokens.next
    if Tokens.comment?(t)
      consolidate_comment_block(t)
      @buffer.pop
    else
      TokenWithComments.new(t)
    end
  else
    @buffer.pop
  end
end

#previous_field_name(last_path = nil) ⇒ Object



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# File 'lib/hocon/impl/parser.rb', line 706

def previous_field_name(last_path = nil)
  if !last_path.nil?
    last_path.render
  elsif @path_stack.empty?
    nil
  else
    @path_stack[0].render
  end
end

#put_back(token) ⇒ Object



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# File 'lib/hocon/impl/parser.rb', line 596

def put_back(token)
  if Tokens.comment?(token.token)
    raise ConfigBugError, "comment token should have been stripped before it was available to put back"
  end
  @buffer.push(token)
end