Class: MilkTea::Formatter

Inherits:
Object
  • Object
show all
Defined in:
lib/milk_tea/tooling/formatter.rb

Defined Under Namespace

Classes: CheckResult

Constant Summary collapse

MODES = 
%i[safe canonical preserve tidy].freeze
DEFAULT_MAX_LINE_LENGTH = 
120

Class Method Summary collapse

Class Method Details

.attribute_application_end_line(lines, start_index) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 517

def self.attribute_application_end_line(lines, start_index)
  return nil unless start_index >= 0 && start_index < lines.length
  return nil unless attribute_application_line?(lines[start_index])

  depth = 0
  open_seen = false
  index = start_index

  while index < lines.length
    bytes = lines[index].bytes
    char_index = 0
    while char_index < bytes.length
      byte = bytes[char_index]
      if byte == 91
        depth += 1
        open_seen = true
      elsif byte == 93 && depth.positive?
        depth -= 1
        return index if open_seen && depth.zero?
      end

      char_index += 1
    end

    index += 1
  end

  nil
end

.attribute_application_line?(line) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 513

def self.attribute_application_line?(line)
  line.strip.start_with?("@[")
end

.blank_line?(line) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 345

def self.blank_line?(line)
  line.empty? || line.bytes.all? { |b| b == 32 || b == 9 }
end

.bodyless_function_header_at?(lines, line_index) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 366

def self.bodyless_function_header_at?(lines, line_index)
  line = lines[line_index]
  return false unless function_line?(line)

  return false unless bodyless_function_line?(line)

  function_indent = leading_indent_width(line)
  cursor = line_index + 1

  while cursor < lines.length
    candidate = lines[cursor]
    if blank_line?(candidate)
      cursor += 1
      next
    end

    candidate_indent = leading_indent_width(candidate)
    if candidate_indent < function_indent
      break
    elsif candidate_indent == function_indent && !function_header_continuation_line?(candidate)
      break
    end

    return false unless bodyless_function_line?(candidate)

    cursor += 1
  end

  true
end

.bodyless_function_line?(line) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 357

def self.bodyless_function_line?(line)
  bytes = line.bytes
  i = bytes.length - 1
  i -= 1 while i >= 0 && (bytes[i] == 32 || bytes[i] == 9)
  return false if i < 0

  bytes[i] != 58 # ':'
end

.build_cst(source, path: nil) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 34

def self.build_cst(source, path: nil)
  CSTBuilder.build(source, path:)
end

.build_long_line_wrap_candidate(line, line_tokens, open_index, close_index, depth) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 715

def self.build_long_line_wrap_candidate(line, line_tokens, open_index, close_index, depth)
  open_token = line_tokens[open_index]
  close_token = line_tokens[close_index]
  nested_group_depth = 0
  comma_tokens = []

  (open_index + 1...close_index).each do |index|
    token = line_tokens[index]
    case token.type
    when :lparen, :lbracket
      nested_group_depth += 1
    when :rparen, :rbracket
      nested_group_depth -= 1 if nested_group_depth.positive?
    when :comma
      comma_tokens << token if nested_group_depth.zero? && token.line == open_token.line
    end
  end

  return nil if comma_tokens.empty?

  start_char = open_token.column - 1
  end_char = close_token.column
  current_start = start_char + 1
  arguments = []

  comma_tokens.each do |comma|
    argument = line[current_start...(comma.column - 1)].to_s.strip
    return nil if argument.empty?

    arguments << argument
    current_start = comma.column
  end

  final_argument = line[current_start...(close_token.column - 1)].to_s.strip
  return nil if final_argument.empty?

  arguments << final_argument
  {
    depth:,
    start_char:,
    end_char:,
    opening_delimiter: open_token.lexeme,
    closing_delimiter: close_token.lexeme,
    arguments:,
  }
end

.build_long_line_wrap_fix(source, line_index, max_line_length: DEFAULT_MAX_LINE_LENGTH, path: nil, tokens: nil, tokens_by_line: nil, validate: true) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 107

def self.build_long_line_wrap_fix(source, line_index, max_line_length: DEFAULT_MAX_LINE_LENGTH, path: nil, tokens: nil, tokens_by_line: nil, validate: true)
  return nil unless max_line_length.to_i.positive?

  lines = source.lines
  return nil unless line_index >= 0 && line_index < lines.length
  return nil if line_inside_external_or_foreign_function_header?(lines, line_index)
  return nil if line_inside_fn_type_signature?(lines, line_index)

  original_line = lines[line_index]
  line = original_line.delete_suffix("\n")
  return nil if line.length <= max_line_length
  return nil unless wrappable_long_line_candidate_text?(line)

  tokens ||= Lexer.lex(source, path:)
  line_tokens = tokens_by_line ? tokens_by_line.fetch(line_index + 1, []) : non_trivia_tokens_on_line(tokens, line_index + 1)
  candidates = long_line_wrap_candidates(line_tokens, line)

  indent = line[/\A\s*/] || ""
  arg_indent = indent + "    "
  line_terminator = original_line.end_with?("\n") ? "\n" : ""

  unless candidates.empty?
    candidates
      .sort_by { |entry| [-(entry[:end_char] - entry[:start_char]), entry[:depth]] }
      .each do |candidate|
        new_text = build_wrapped_delimited_group_text(
          line,
          candidate,
          indent:,
          item_indent: arg_indent,
          line_terminator:,
        )
        next if new_text == original_line

        updated_lines = lines.dup
        updated_lines[line_index..line_index] = [new_text]
        Parser.parse(updated_lines.join, path:) if validate

        return {
          start_line_idx: line_index,
          end_line_idx: line_index,
          new_text:,
        }
      rescue StandardError
        next if validate
      end
  end

  logical_chain_fix = build_wrapped_logical_chain_fix(
    lines,
    line_index,
    line,
    line_tokens,
    line_terminator:,
    path:,
    validate:,
  )
  return logical_chain_fix if logical_chain_fix

  nil
rescue StandardError
  nil
end

.build_wrapped_delimited_group_text(line, candidate, indent:, item_indent:, line_terminator:) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 171

def self.build_wrapped_delimited_group_text(line, candidate, indent:, item_indent:, line_terminator:)
  new_text = +"#{line[0...candidate[:start_char]]}#{candidate[:opening_delimiter]}\n"
  candidate[:arguments].each_with_index do |argument, index|
    suffix = index < candidate[:arguments].length - 1 ? "," : ""
    new_text << "#{item_indent}#{argument}#{suffix}\n"
  end
  new_text << "#{indent}#{candidate[:closing_delimiter]}#{line[candidate[:end_char]..].to_s}#{line_terminator}"
  new_text
end

.build_wrapped_logical_chain_fix(lines, line_index, line, line_tokens, line_terminator:, path:, validate: true) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 181

def self.build_wrapped_logical_chain_fix(lines, line_index, line, line_tokens, line_terminator:, path:, validate: true)
  candidate = logical_chain_wrap_candidate(line_tokens, line)
  return nil unless candidate

  indent = line[/\A\s*/] || ""
  item_indent = indent + "    "
  new_text = build_wrapped_logical_chain_text(
    line,
    candidate,
    indent:,
    item_indent:,
    line_terminator:,
  )
  return nil if new_text == lines[line_index]

  updated_lines = lines.dup
  updated_lines[line_index..line_index] = [new_text]
  Parser.parse(updated_lines.join, path:) if validate

  {
    start_line_idx: line_index,
    end_line_idx: line_index,
    new_text:,
  }
rescue StandardError
  nil
end

.build_wrapped_logical_chain_text(line, candidate, indent:, item_indent:, line_terminator:) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 209

def self.build_wrapped_logical_chain_text(line, candidate, indent:, item_indent:, line_terminator:)
  new_text = +"#{line[0...candidate[:start_char]]}(\n"
  new_text << "#{item_indent}#{candidate[:segments].first}\n"
  candidate[:operators].each_with_index do |operator, index|
    new_text << "#{item_indent}#{operator} #{candidate[:segments][index + 1]}\n"
  end
  new_text << "#{indent})#{line[candidate[:end_char]..].to_s}#{line_terminator}"
  new_text
end

.canonical_format(source, path:, profile: nil) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 44

def self.canonical_format(source, path:, profile: nil)
  lexed = profile_phase(profile, "format.lex") { Lexer.lex_with_trivia(source, path:) }
  ast = profile_phase(profile, "format.parse") { Parser.parse(source, path:) }
  profile_phase(profile, "format.ast") { PrettyPrinter.format_ast(ast, trivia: lexed.trivia) }
end

.check_source(source, path: nil, mode: :canonical, max_line_length: nil, profile: nil) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 27

def self.check_source(source, path: nil, mode: :canonical, max_line_length: nil, profile: nil)
  profile_phase(profile, "format") do
    formatted = format_source(source, path:, mode:, max_line_length:, profile:)
    CheckResult.new(changed: source != formatted, formatted_source: formatted)
  end
end

.extending_block_header_line?(line) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 491

def self.extending_block_header_line?(line)
  stripped = line.strip
  return false unless stripped.end_with?(":")

  stripped.start_with?("extending ")
end

.external_or_foreign_function_header_line?(line) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 466

def self.external_or_foreign_function_header_line?(line)
  line.strip.match?(/\A(?:[A-Za-z_]\w*\s+)*(?:external|foreign)\s+function\b/)
end

.fn_type_signature_start_line?(line) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 484

def self.fn_type_signature_start_line?(line)
  stripped = line.strip
  return true if stripped.match?(/\Atype\s+[A-Za-z_]\w*\s*=\s*fn\s*\(/)

  stripped.match?(/\A[A-Za-z_]\w*\s*:\s*fn\s*\(/)
end

.format_source(source, path: nil, mode: :safe, max_line_length: nil, profile: nil) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 14

def self.format_source(source, path: nil, mode: :safe, max_line_length: nil, profile: nil)
  validate_mode!(mode)

  case mode
  when :safe, :canonical
    canonical_format(source, path:, profile:)
  when :preserve
    preserve_format(source, path:, profile:)
  when :tidy
    tidy_format(source, path:, max_line_length: resolve_max_line_length(path, explicit: max_line_length), profile:)
  end
end

.function_header_continuation_line?(line) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 404

def self.function_header_continuation_line?(line)
  stripped = line.strip
  return false if stripped.empty?

  stripped.start_with?(")", "]", ",", "->")
end

.function_line?(line) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 319

def self.function_line?(line)
  bytes = line.bytes
  i = 0

  i += 1 while i < bytes.length && (bytes[i] == 32 || bytes[i] == 9)
  return false if i >= bytes.length

  loop do
    word_start = i
    return false unless identifier_head_byte?(bytes[i])

    i += 1
    i += 1 while i < bytes.length && identifier_tail_byte?(bytes[i])
    word = bytes[word_start...i].pack("C*")

    if word == "function"
      return i < bytes.length && (bytes[i] == 32 || bytes[i] == 9)
    end

    return false unless i < bytes.length && (bytes[i] == 32 || bytes[i] == 9)

    i += 1 while i < bytes.length && (bytes[i] == 32 || bytes[i] == 9)
    return false if i >= bytes.length
  end
end

.identifier_head_byte?(byte) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 349

def self.identifier_head_byte?(byte)
  (byte >= 65 && byte <= 90) || (byte >= 97 && byte <= 122) || byte == 95
end

.identifier_tail_byte?(byte) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 353

def self.identifier_tail_byte?(byte)
  identifier_head_byte?(byte) || (byte >= 48 && byte <= 57)
end

.interface_block_header_line?(line) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 498

def self.interface_block_header_line?(line)
  stripped = line.strip
  return false unless stripped.end_with?(":")

  stripped.start_with?("interface ")
end

.leading_indent_width(line) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 397

def self.leading_indent_width(line)
  bytes = line.bytes
  i = 0
  i += 1 while i < bytes.length && (bytes[i] == 32 || bytes[i] == 9)
  i
end

.line_in_function_header_span?(lines, start_index, target_index) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 424

def self.line_in_function_header_span?(lines, start_index, target_index)
  return false if target_index < start_index

  function_indent = leading_indent_width(lines[start_index])
  header_end = start_index
  cursor = start_index + 1

  while cursor < lines.length
    candidate = lines[cursor]
    if blank_line?(candidate)
      cursor += 1
      next
    end

    candidate_indent = leading_indent_width(candidate)
    if candidate_indent < function_indent
      break
    elsif candidate_indent == function_indent && !function_header_continuation_line?(candidate)
      break
    end

    header_end = cursor
    cursor += 1
  end

  target_index <= header_end
end

.line_inside_attribute_application?(lines, line_index) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 547

def self.line_inside_attribute_application?(lines, line_index)
  start_index = line_index
  while start_index >= 0
    if attribute_application_line?(lines[start_index])
      end_index = attribute_application_end_line(lines, start_index)
      return false unless end_index

      return line_index <= end_index
    end

    break if function_line?(lines[start_index])
    start_index -= 1
  end

  false
end

.line_inside_bodyless_function_header?(lines, line_index) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 411

def self.line_inside_bodyless_function_header?(lines, line_index)
  start_index = line_index
  while start_index >= 0
    if function_line?(lines[start_index])
      return bodyless_function_header_at?(lines, start_index) && line_in_function_header_span?(lines, start_index, line_index)
    end

    start_index -= 1
  end

  false
end

.line_inside_external_or_foreign_function_header?(lines, line_index) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 452

def self.line_inside_external_or_foreign_function_header?(lines, line_index)
  start_index = line_index
  while start_index >= 0
    if external_or_foreign_function_header_line?(lines[start_index])
      return line_in_function_header_span?(lines, start_index, line_index)
    end

    break if function_line?(lines[start_index])
    start_index -= 1
  end

  false
end

.line_inside_fn_type_signature?(lines, line_index) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 470

def self.line_inside_fn_type_signature?(lines, line_index)
  start_index = line_index
  while start_index >= 0
    if fn_type_signature_start_line?(lines[start_index])
      return line_in_function_header_span?(lines, start_index, line_index)
    end

    break if function_line?(lines[start_index]) || external_or_foreign_function_header_line?(lines[start_index])
    start_index -= 1
  end

  false
end

.line_is_comment?(line) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 509

def self.line_is_comment?(line)
  line.strip.start_with?("#")
end

.line_is_import?(line) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 505

def self.line_is_import?(line)
  line.strip.start_with?("import ")
end

.logical_chain_wrap_candidate(line_tokens, line) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 651

def self.logical_chain_wrap_candidate(line_tokens, line)
  return nil if line_tokens.length < 4

  header_length = case line_tokens.first.type
                  when :if, :while
                    1
                  when :else
                    line_tokens[1]&.type == :if ? 2 : 0
                  else
                    0
                  end
  return nil if header_length.zero?

  colon_token = line_tokens.reverse.find { |token| token.type == :colon }
  return nil unless colon_token

  expression_start_token = line_tokens[header_length]
  return nil unless expression_start_token

  start_char = expression_start_token.column - 1
  return nil if line[start_char] == "("

  nested_group_depth = 0
  operators = []
  segments = []
  current_start = start_char

  line_tokens[header_length...line_tokens.index(colon_token)].each do |token|
    case token.type
    when :lparen, :lbracket
      nested_group_depth += 1
    when :rparen, :rbracket
      nested_group_depth -= 1 if nested_group_depth.positive?
    when :and, :or
      next unless nested_group_depth.zero?

      segment = line[current_start...(token.column - 1)].to_s.strip
      return nil if segment.empty?

      segments << segment
      operators << token.lexeme
      current_start = token.column - 1 + token.lexeme.length
    end
  end

  return nil if operators.empty?

  final_segment = line[current_start...(colon_token.column - 1)].to_s.strip
  return nil if final_segment.empty?

  segments << final_segment
  {
    start_char:,
    end_char: colon_token.column - 1,
    operators:,
    segments:,
  }
end

.long_line_wrap_candidates(line_tokens, line) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 624

def self.long_line_wrap_candidates(line_tokens, line)
  stack = []
  candidates = []

  line_tokens.each_with_index do |token, index|
    case token.type
    when :lparen, :lbracket
      stack << { token:, index:, depth: stack.length }
    when :rparen, :rbracket
      opening = stack.pop
      next unless opening
      next unless matching_delimiter_pair?(opening[:token].type, token.type)

      candidate = build_long_line_wrap_candidate(
        line,
        line_tokens,
        opening[:index],
        index,
        opening[:depth],
      )
      candidates << candidate if candidate
    end
  end

  candidates
end

.matching_delimiter_pair?(opening_type, closing_type) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 710

def self.matching_delimiter_pair?(opening_type, closing_type)
  (opening_type == :lparen && closing_type == :rparen) ||
    (opening_type == :lbracket && closing_type == :rbracket)
end

.non_trivia_tokens_by_line(tokens) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 773

def self.non_trivia_tokens_by_line(tokens)
  tokens.each_with_object(Hash.new { |hash, line| hash[line] = [] }) do |token, by_line|
    next if %i[newline indent dedent eof].include?(token.type)

    by_line[token.line] << token
  end
end

.non_trivia_tokens_on_line(tokens, line_number) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 769

def self.non_trivia_tokens_on_line(tokens, line_number)
  tokens.select { |token| token.line == line_number && !%i[newline indent dedent eof].include?(token.type) }
end

.normalize_blank_lines(source, path: nil) ⇒ Object

Enforce blank-line rules:

- exactly 2 blank lines before top-level function definitions with a body
- exactly 2 blank lines before top-level extending blocks
- bodyless function declarations: 1 blank line before the first declaration,
then 0 blank lines between consecutive declarations
- at most 1 blank line everywhere else (constants, variable declarations, expressions)
- exactly 1 trailing newline at EOF


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# File 'lib/milk_tea/tooling/formatter.rb', line 226

def self.normalize_blank_lines(source, path: nil)
  lines = source.lines(chomp: true)
  result = []
  blank_run = 0
  emitted_content = false
  previous_content_line = nil
  previous_content_index = nil
  previous_top_level_declaration_group = nil
  previous_content_was_bodyful_function = false
  previous_content_was_comment = false

  lines.each_with_index do |line, line_index|
    if blank_line?(line)
      blank_run += 1
    else
      if emitted_content
        current_top_level_group = top_level_declaration_group(line)
        decorated_function_index = top_level_function_attached_to_attribute_start(lines, line_index)
        needed = if decorated_function_index
          if bodyless_function_header_at?(lines, decorated_function_index)
            1
          else
            2
          end
        elsif previous_content_index && line_inside_attribute_application?(lines, previous_content_index)
          0
        elsif extending_block_header_line?(line)
          if previous_content_was_comment
            1 # 1 blank line between a comment block and an extending block
          else
            2 # exactly 2 blank lines before extending blocks
          end
        elsif function_line?(line)
           current_bodyless_function_header = bodyless_function_header_at?(lines, line_index)
           if current_bodyless_function_header
             if previous_content_index && line_inside_bodyless_function_header?(lines, previous_content_index)
               0 # Keep consecutive declaration-style functions tightly packed.
             elsif previous_content_line && interface_block_header_line?(previous_content_line)
               0 # First interface method should not have leading blank lines.
             else
               1 # Separate declaration-style functions from preceding non-function content.
             end
           elsif previous_content_line && extending_block_header_line?(previous_content_line)
             0 # First method in an extending block should not have leading blank lines.
           elsif previous_content_was_comment
             1 # 1 blank line between a comment block and a function
           elsif previous_content_was_bodyful_function
             2 # 2 blank lines between consecutive function definitions
           else
             2 # 2 blank lines before first function in a scope (after const/struct/enum/import etc.)
           end
        elsif current_top_level_group
          if current_top_level_group == :struct && previous_top_level_declaration_group == :struct
            1
          elsif current_top_level_group == :enum && previous_top_level_declaration_group == :enum
            1
          elsif current_top_level_group == :union && previous_top_level_declaration_group == :union
            1
          elsif previous_top_level_declaration_group && current_top_level_group != previous_top_level_declaration_group
            1
          else
            [blank_run, 1].min
          end
        else
          [blank_run, 1].min  # max 1 blank line elsewhere
        end
        needed.times { result << "" }
      end
      result << line
      blank_run = 0
      emitted_content = true
      previous_content_line = line
      previous_content_index = line_index
      current_top_level_group = top_level_declaration_group(line)
      previous_top_level_declaration_group = current_top_level_group if current_top_level_group
      if decorated_function_index
        unless bodyless_function_header_at?(lines, decorated_function_index)
          previous_content_was_bodyful_function = true
        end
      elsif function_line?(line) && !bodyless_function_header_at?(lines, line_index)
        previous_content_was_bodyful_function = true
      elsif current_top_level_group || extending_block_header_line?(line) || interface_block_header_line?(line) || line_is_import?(line) || line_is_comment?(line)
        previous_content_was_bodyful_function = false
      end
      previous_content_was_comment = line_is_comment?(line)
    end
   end

  return "" if result.empty?

  "#{result.join("\n")}\n"
end

.preserve_format(source, path:, profile: nil) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 50

def self.preserve_format(source, path:, profile: nil)
  cst = profile_phase(profile, "format.cst") { build_cst(source, path:) }
  profile_phase(profile, "format.cst_fmt") { CSTFormatter.format(cst) }
end

.profile_phase(profile, name) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 38

def self.profile_phase(profile, name)
  return yield unless profile

  profile.measure(name) { yield }
end

.resolve_max_line_length(path = nil, explicit: nil) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 62

def self.resolve_max_line_length(path = nil, explicit: nil)
  value = explicit
  if (!value || value.to_i <= 0) && defined?(Linter) && Linter.respond_to?(:load_config)
    value = Linter.load_config(path)&.fetch(:max_line_length, nil)
  end

  value = value.to_i if value
  value&.positive? ? value : DEFAULT_MAX_LINE_LENGTH
end

.tidy_format(source, path:, max_line_length: DEFAULT_MAX_LINE_LENGTH, profile: nil) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 55

def self.tidy_format(source, path:, max_line_length: DEFAULT_MAX_LINE_LENGTH, profile: nil)
  cst = profile_phase(profile, "format.cst") { build_cst(source, path:) }
  normalized = profile_phase(profile, "format.normalize") { CSTFormatter.format_normalized(cst) }
  wrapped = profile_phase(profile, "format.wrap") { wrap_long_argument_lists(normalized, max_line_length:, path:) }
  profile_phase(profile, "format.blank_lines") { normalize_blank_lines(wrapped, path:) }
end

.top_level_declaration_group(line) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 588

def self.top_level_declaration_group(line)
  stripped = line.strip
  return nil if stripped.empty?
  return nil unless leading_indent_width(line).zero?

  first_token = stripped[/\A[A-Za-z_][A-Za-z0-9_]*/]
  return nil unless first_token

  case first_token
  when "link", "include", "compiler_flag"
    :directive
  when "opaque"
    :opaque
  when "type"
    :type
  when "struct"
    :struct
  when "union"
    :union
  when "variant"
    :variant
  when "enum"
    :enum
  when "flags"
    :flags
  when "const"
    :const
  when "var"
    :var
  when "external"
    stripped.match?(/\Aexternal\s+function\b/) ? :external_function : :external
  else
    nil
  end
end

.top_level_function_attached_to_attribute_start(lines, line_index) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 564

def self.top_level_function_attached_to_attribute_start(lines, line_index)
  return nil unless leading_indent_width(lines[line_index]).zero?
  return nil unless attribute_application_line?(lines[line_index])
  return nil if line_index.positive? && line_inside_attribute_application?(lines, line_index - 1)

  cursor = line_index
  loop do
    end_index = attribute_application_end_line(lines, cursor)
    return nil unless end_index

    cursor = end_index + 1
    cursor += 1 while cursor < lines.length && blank_line?(lines[cursor])
    return nil if cursor >= lines.length

    if attribute_application_line?(lines[cursor]) && leading_indent_width(lines[cursor]).zero?
      next
    end

    return cursor if function_line?(lines[cursor]) && leading_indent_width(lines[cursor]).zero?

    return nil
  end
end

.validate_mode!(mode) ⇒ Object

Raises:



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# File 'lib/milk_tea/tooling/formatter.rb', line 781

def self.validate_mode!(mode)
  return if MODES.include?(mode)

  raise FormatterError, "unknown formatter mode #{mode.inspect}"
end

.wrap_long_argument_lists(source, max_line_length: DEFAULT_MAX_LINE_LENGTH, path: nil) ⇒ Object 



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# File 'lib/milk_tea/tooling/formatter.rb', line 72

def self.wrap_long_argument_lists(source, max_line_length: DEFAULT_MAX_LINE_LENGTH, path: nil)
  return source unless max_line_length.to_i.positive?

  current = source
  100.times do
    lines = current.lines
    tokens = Lexer.lex(current, path:)
    tokens_by_line = non_trivia_tokens_by_line(tokens)
    fix = nil

    lines.each_index do |line_index|
      next unless lines[line_index].delete_suffix("\n").length > max_line_length

      fix = build_long_line_wrap_fix(current, line_index, max_line_length:, path:, tokens:, tokens_by_line:)
      break if fix
    end

    break unless fix

    updated_lines = current.lines
    updated_lines[fix[:start_line_idx]..fix[:end_line_idx]] = [fix[:new_text]]
    updated = updated_lines.join
    break if updated == current

    current = updated
  end

  return current if current == source

  Parser.parse(current, path:)
  current
rescue StandardError
  source
end

.wrappable_long_line_candidate_text?(line) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/tooling/formatter.rb', line 762

def self.wrappable_long_line_candidate_text?(line)
  return true if line.include?("(") || line.include?("[")
  return true if line.include?(" and ") || line.include?(" or ")

  false
end