class SyntaxSuggest::CodeSearch

Searches code for a syntax error

There are three main phases in the algorithm:

Sanitize/format input source
Search for invalid blocks
Format invalid blocks into something meaninful

This class handles the part.

The bulk of the heavy lifting is done in:

- CodeFrontier (Holds information for generating blocks and determining if we can stop searching)
- ParseBlocksFromLine (Creates blocks into the frontier)
- BlockExpand (Expands existing blocks to search more code)

## Syntax error detection

When the frontier holds the syntax error, we can stop searching

search = CodeSearch.new(<<~EOM)
  def dog
    def lol
  end
EOM

search.call

search.invalid_blocks.map(&:to_s) # =>
# => ["def lol\n"]

Attributes

code_lines[R]

frontier[R]

invalid_blocks[R]

record_dir[R]

Public Class Methods

new(source, record_dir: DEFAULT_VALUE) click to toggle source

# File lib/syntax_suggest/code_search.rb, line 44
def initialize(source, record_dir: DEFAULT_VALUE)
  record_dir = if record_dir == DEFAULT_VALUE
    (ENV["SYNTAX_SUGGEST_RECORD_DIR"] || ENV["SYNTAX_SUGGEST_DEBUG"]) ? "tmp" : nil
  else
    record_dir
  end

  if record_dir
    @record_dir = SyntaxSuggest.record_dir(record_dir)
    @write_count = 0
  end

  @tick = 0
  @source = source
  @name_tick = Hash.new { |hash, k| hash[k] = 0 }
  @invalid_blocks = []

  @code_lines = CleanDocument.new(source: source).call.lines

  @frontier = CodeFrontier.new(code_lines: @code_lines)
  @block_expand = BlockExpand.new(code_lines: @code_lines)
  @parse_blocks_from_indent_line = ParseBlocksFromIndentLine.new(code_lines: @code_lines)
end

Public Instance Methods

call() click to toggle source

Main search loop

# File lib/syntax_suggest/code_search.rb, line 123
def call
  until frontier.holds_all_syntax_errors?
    @tick += 1

    if frontier.expand?
      expand_existing
    else
      create_blocks_from_untracked_lines
    end
  end

  @invalid_blocks.concat(frontier.detect_invalid_blocks)
  @invalid_blocks.sort_by! { |block| block.starts_at }
  self
end

create_blocks_from_untracked_lines() click to toggle source

Parses the most indented lines into blocks that are marked and added to the frontier

# File lib/syntax_suggest/code_search.rb, line 100
def create_blocks_from_untracked_lines
  max_indent = frontier.next_indent_line&.indent

  while (line = frontier.next_indent_line) && (line.indent == max_indent)
    @parse_blocks_from_indent_line.each_neighbor_block(frontier.next_indent_line) do |block|
      push(block, name: "add")
    end
  end
end

expand_existing() click to toggle source

Given an already existing block in the frontier, expand it to see if it contains our invalid syntax

# File lib/syntax_suggest/code_search.rb, line 112
def expand_existing
  block = frontier.pop
  return unless block

  record(block: block, name: "before-expand")

  block = @block_expand.call(block)
  push(block, name: "expand")
end

push(block, name:) click to toggle source

# File lib/syntax_suggest/code_search.rb, line 91
def push(block, name:)
  record(block: block, name: name)

  block.mark_invisible if block.valid?
  frontier << block
end

record(block:, name: "record") click to toggle source

Used for debugging

# File lib/syntax_suggest/code_search.rb, line 69
def record(block:, name: "record")
  return unless @record_dir
  @name_tick[name] += 1
  filename = "#{@write_count += 1}-#{name}-#{@name_tick[name]}-(#{block.starts_at}__#{block.ends_at}).txt"
  if ENV["SYNTAX_SUGGEST_DEBUG"]
    puts "\n\n==== #{filename} ===="
    puts "\n```#{block.starts_at}..#{block.ends_at}"
    puts block
    puts "```"
    puts "  block indent:      #{block.current_indent}"
  end
  @record_dir.join(filename).open(mode: "a") do |f|
    document = DisplayCodeWithLineNumbers.new(
      lines: @code_lines.select(&:visible?),
      terminal: false,
      highlight_lines: block.lines
    ).call

    f.write("    Block lines: #{block.starts_at..block.ends_at} (#{name}) \n\n#{document}")
  end
end