lib/autotest.rb



require 'find'
require 'rbconfig'

$TESTING = false unless defined? $TESTING

##
# Autotest continuously scans the files in your project for changes
# and runs the appropriate tests.  Test failures are run until they
# have all passed. Then the full test suite is run to ensure that
# nothing else was inadvertantly broken.
#
# If you want Autotest to start over from the top, hit ^C once.  If
# you want Autotest to quit, hit ^C twice.
#
# Rails:
#
# The autotest command will automatically discover a Rails directory
# by looking for config/environment.rb. When Rails is discovered,
# autotest uses RailsAutotest to perform file mappings and other work.
# See RailsAutotest for details.
#
# Plugins:
#
# Plugins are available by creating a .autotest file either in your
# project root or in your home directory. You can then write event
# handlers in the form of:
#
#   Autotest.add_hook hook_name { |autotest| ... }
#
# The available hooks are listed in +ALL_HOOKS+.
#
# See example_dot_autotest.rb for more details.
#
# If a hook returns a true value, it signals to autotest that the hook
# was handled and should not continue executing hooks.
#
# Naming:
#
# Autotest uses a simple naming scheme to figure out how to map
# implementation files to test files following the Test::Unit naming
# scheme.
#
# * Test files must be stored in test/
# * Test files names must start with test_
# * Test class names must start with Test
# * Implementation files must be stored in lib/
# * Implementation files must match up with a test file named
#   test_.*implementation.rb
#
# Strategy:
#
# 1. Find all files and associate them from impl <-> test.
# 2. Run all tests.
# 3. Scan for failures.
# 4. Detect changes in ANY (ruby?. file, rerun all failures + changed files.
# 5. Until 0 defects, goto 3.
# 6. When 0 defects, goto 2.

class Autotest

  VERSION = File.read( File.join(File.dirname(__FILE__),'..','VERSION') ).strip

  RUBY19 = defined? Encoding

  T0 = Time.at 0

  ALL_HOOKS = [ :all_good, :died, :green, :initialize, :interrupt, :quit,
                :ran_command, :red, :reset, :run_command, :updated, :waiting ]

  @@options = {}
  def self.options;@@options;end
  def options;@@options;end


  HOOKS = Hash.new { |h,k| h[k] = [] } #unfound keys are []
  unless defined? WINDOZE then
    WINDOZE = /mswin|mingw|windows/ =~ Config::CONFIG['host_os']
    SEP = WINDOZE ? '&' : ';'
  end

  @@discoveries = []

  ##
  # Provide some help 
  def self.usage
    help = [
            "autotest [options]",
            nil,
            "Autotest automatically tests code that has changed.",
            "It assumes the code is in lib, and tests are in tests.",
            "Autotest uses plugins to control what happens.",
            "You configure plugins with require statements in the",
            ".autotest file in your project base directory,",
            "and a default configuration for all your projects",
            "in the .autotest file in your home directory.",

            nil,
            "options:",
            "\t-h",
            "\t-help\t\tYou're looking at it.",
            nil,
            "\t-v\t\tBe verbose.",
            "\t\t\tPrints files that autotest doesn't know how to map to",
            "\t\t\ttests.",
            nil,
            "\t-q\t\tBe more quiet.",
            nil,
            "\t-f\t\tFast start.",
            "\t\t\tDoesn't initially run tests at start.",
           ]
    STDERR.puts help.join("\n")
  end

  ##
  # Call Autotest.usage then exit with 1.
  def self.usage_with_exit
    self.usage
    exit 1
  end


  ##
  # Add a proc to the collection of discovery procs. See
  # +autodiscover+.

  def self.add_discovery &proc
    @@discoveries << proc
  end

  ##
  # Automatically find all potential autotest runner styles by
  # searching your loadpath, vendor/plugins, and rubygems for
  # "autotest/discover.rb". If found, that file is loaded and it
  # should register discovery procs with autotest using
  # +add_discovery+. That proc should return one or more strings
  # describing the user's current environment. Those styles are then
  # combined to dynamically invoke an autotest plugin to suite your
  # environment. That plugin should define a subclass of Autotest with
  # a corresponding name.
  #
  # === Process:
  #
  # 1. All autotest/discover.rb files loaded.
  # 2. Those procs determine your styles (eg ["rails", "rspec"]).
  # 3. Require file by sorting styles and joining (eg 'autotest/rails_rspec').
  # 4. Invoke run method on appropriate class (eg Autotest::RailsRspec.run).
  #
  # === Example autotest/discover.rb:
  #
  #   Autotest.add_discovery do
  #     "rails" if File.exist? 'config/environment.rb'
  #   end
  #
  def self.autodiscover
    require 'rubygems'
    begin
      require 'win32console' if WINDOZE
    rescue LoadError
    end

    with_current_path_in_load_path do
      # search load paths for autotest/discover.rb and load em all
      Gem.find_files("autotest/discover").each do |f|
        load f
      end
    end

    #call all discover procs an determine style
    @@discoveries.map{ |proc| proc.call }.flatten.compact.sort.uniq
  end

  ##
  # Initialize and run the system.

  def self.run
    new.run
  end

  attr_writer :known_files
  attr_accessor(:completed_re,
                :extra_class_map,
                :extra_files,
                :failed_results_re,
                :files_to_test,
                :find_order,
                :interrupted,
                :last_mtime,
                :libs,
                :order,
                :output,
                :results,
                :sleep,
                :tainted,
                :testlib,
                :find_directories,
                :unit_diff,
                :wants_to_quit)

  alias tainted? tainted

  ##
  # Initialize the instance and then load the user's .autotest file, if any.

  def initialize
    # these two are set directly because they're wrapped with
    # add/remove/clear accessor methods
    @exception_list = []
    @test_mappings = []

    self.completed_re = /\d+ tests, \d+ assertions, \d+ failures, \d+ errors/
    self.extra_class_map   = {}
    self.extra_files       = []
    self.failed_results_re = /^\s+\d+\) (?:Failure|Error):\n(.*?)\((.*?)\)/
    self.files_to_test     = new_hash_of_arrays
    self.find_order        = []
    self.known_files       = nil
    self.libs              = %w[. lib test].join(File::PATH_SEPARATOR)
    self.order             = :random
    self.output            = $stderr
    self.sleep             = 1
    self.testlib           = "test/unit"
    self.find_directories  = ['.']
    self.unit_diff         = "#{File.expand_path("#{File.dirname(__FILE__)}/../bin/unit_diff")} -u"

    #add Test::Unit mappings
    #file in /lib -> run test in /test
    self.add_mapping(/^lib\/.*\.rb$/) do |filename, _|
      possible = File.basename(filename).gsub '_', '_?'
      files_matching %r%^test/.*#{possible}$%
    end

    #file in /test -> run it
    self.add_mapping(/^test.*\/test_.*rb$/) do |filename, _|
      filename
    end

    #execute custom extensions
    load_custom_extensions(options[:rc])
  end

  def load_custom_extensions(config_file)
    configs = ['./.autotest']
    if config_file
      configs << File.expand_path(config_file)
    else
      configs << File.expand_path('~/.autotest')
    end
    configs.each do |f|
      load f if File.exist? f
    end
  end

  ##
  # Repeatedly run failed tests, then all tests, then wait for changes
  # and carry on until killed.

  def run
    hook :initialize
    reset
    add_sigint_handler

    self.last_mtime = Time.now if options[:no_full_after_start]

    loop do
      begin # ^c handler
        get_to_green
        if tainted? and not options[:no_full_after_failed]
          rerun_all_tests
        else
          hook :all_good
        end
        wait_for_changes
      rescue Interrupt
        break if wants_to_quit
        reset
      end
    end
    hook :quit
  rescue Exception => err
    hook :died, err
  end

  ##
  # Keep running the tests after a change, until all pass.

  def get_to_green
    begin
      run_tests
      wait_for_changes unless all_good
    end until all_good
  end

  ##
  # Look for files to test then run the tests and handle the results.

  def run_tests
    hook :run_command

    new_mtime = self.find_files_to_test
    return unless new_mtime
    self.last_mtime = new_mtime

    cmd = self.make_test_cmd self.files_to_test
    return if cmd.empty?

    puts cmd unless options[:quiet]

    old_sync = $stdout.sync
    $stdout.sync = true
    self.results = []
    line = []
    begin
      open("| #{cmd}", "r") do |f|
        until f.eof? do
          c = f.getc or break
          print (c.is_a?(Fixnum) ? c.chr : c)
          line << c
          if c == ?\n then
            self.results << if RUBY19 then
                              line.join
                            else
                              line.pack "c*"
                            end
            line.clear
          end
        end
      end
    ensure
      $stdout.sync = old_sync
    end
    hook :ran_command
    self.results = self.results.join

    handle_results(self.results)
  end

  ############################################################
  # Utility Methods, not essential to reading of logic

  ##
  # Installs a sigint handler.

  def add_sigint_handler
    trap 'INT' do
      if self.interrupted then
        self.wants_to_quit = true
      else
        unless hook :interrupt then
          puts "Interrupt a second time to quit"
          self.interrupted = true
          Kernel.sleep 1.5
        end
        raise Interrupt, nil # let the run loop catch it
      end
    end
  end

  ##
  # If there are no files left to test (because they've all passed),
  # then all is good.

  def all_good
    files_to_test.empty?
  end

  ##
  # Convert a path in a string, s, into a class name, changing
  # underscores to CamelCase, etc.

  def path_to_classname(s)
    sep = File::SEPARATOR
    f = s.sub(/^test#{sep}/, '').sub(/\.rb$/, '').split(sep)
    f = f.map { |path| path.split(/_|(\d+)/).map { |seg| seg.capitalize }.join }
    f = f.map { |path| path =~ /^Test/ ? path : "Test#{path}"  }

    f.join('::')
  end

  ##
  # Returns a hash mapping a file name to the known failures for that
  # file.

  def consolidate_failures(failed)
    filters = new_hash_of_arrays

    class_map = Hash[*self.find_order.grep(/^test/).map { |f| # TODO: ugly
                       [path_to_classname(f), f]
                     }.flatten]
    class_map.merge!(self.extra_class_map)

    failed.each do |method, klass|
      if class_map.has_key? klass then
        filters[class_map[klass]] << method
      else
        output.puts "Unable to map class #{klass} to a file"
      end
    end

    return filters
  end

  ##
  # Find the files to process, ignoring temporary files, source
  # configuration management files, etc., and return a Hash mapping
  # filename to modification time.

  def find_files
    result = {}
    targets = self.find_directories + self.extra_files
    self.find_order.clear

    targets.each do |target|
      order = []
      Find.find(target) do |f|
        Find.prune if f =~ self.exceptions

        next if test ?d, f
        next if f =~ /(swp|~|rej|orig)$/ # temporary/patch files
        next if f =~ /\/\.?#/            # Emacs autosave/cvs merge files

        filename = f.sub(/^\.\//, '')

        result[filename] = File.stat(filename).mtime rescue next
        order << filename
      end
      self.find_order.push(*order.sort)
    end

    return result
  end

  ##
  # Find the files which have been modified, update the recorded
  # timestamps, and use this to update the files to test. Returns
  # the latest mtime of the files modified or nil when nothing was
  # modified.
  def find_files_to_test(files=find_files)
    updated = files.select { |filename, mtime| self.last_mtime < mtime }

    unless updated.empty? or self.last_mtime.to_i == 0 #nothing to update or initial run
      p updated if options[:verbose]
      hook :updated, updated
    end

    updated.map { |f,m| test_files_for(f) }.flatten.uniq.each do |filename|
      self.files_to_test[filename] # creates key with default value
    end

    if updated.empty? then
      nil
    else
      files.values.max
    end
  end

  ##
  # Check results for failures, set the "bar" to red or green, and if
  # there are failures record this.

  def handle_results(results)
    failed = results.scan(self.failed_results_re)
    completed = results =~ self.completed_re

    self.files_to_test = consolidate_failures failed if completed

    color = completed && self.files_to_test.empty? ? :green : :red
    hook color unless $TESTING

    self.tainted = true unless self.files_to_test.empty?
  end

  ##
  # Lazy accessor for the known_files hash.

  def known_files
    unless @known_files then
      @known_files = Hash[*find_order.map { |f| [f, true] }.flatten]
    end
    @known_files
  end

  ##
  # Generate the commands to test the supplied files

  def make_test_cmd files_to_test
    cmds = []
    full, partial = reorder(files_to_test).partition { |k,v| v.empty? }
    base_cmd = "#{ruby} -I#{libs} -rubygems"

    unless full.empty? then
      classes = full.map {|k,v| k}.flatten.uniq
      if options[:parallel] and classes.size > 1
        cmds << "parallel_test #{escape_filenames(classes).join(' ')}"
      else
        classes.unshift testlib
        cmds << "#{base_cmd} -e \"[#{escape_filenames(classes).join(', ')}].each { |f| require f }\" | #{unit_diff}"
      end
    end

    partial.each do |klass, methods|
      regexp = Regexp.union(*methods).source
      cmds << "#{base_cmd} #{klass} -n \"/^(#{regexp})$/\" | #{unit_diff}"
    end

    cmds.join("#{SEP} ")
  end

  def escape_filenames(classes)
    classes.map{|klass| "'#{klass}'"}
  end

  def new_hash_of_arrays
    Hash.new { |h,k| h[k] = [] }
  end

  def reorder files_to_test
    case self.order
    when :alpha then
      files_to_test.sort_by { |k,v| k }
    when :reverse then
      files_to_test.sort_by { |k,v| k }.reverse
    when :random then
      max = files_to_test.size
      files_to_test.sort_by { |k,v| rand(max) }
    when :natural then
      (self.find_order & files_to_test.keys).map { |f| [f, files_to_test[f]] }
    else
      raise "unknown order type: #{self.order.inspect}"
    end
  end

  ##
  # Rerun the tests from cold (reset state)

  def rerun_all_tests
    reset
    run_tests

    hook :all_good if all_good
  end

  ##
  # Clear all state information about test failures and whether
  # interrupts will kill autotest.

  def reset
    self.files_to_test.clear
    self.find_order.clear
    self.interrupted = false
    self.known_files = nil
    self.last_mtime = T0
    self.tainted = false
    self.wants_to_quit = false

    hook :reset
  end

  ##
  # Determine and return the path of the ruby executable.

  def ruby
    ruby = ENV['RUBY']
    ruby ||= File.join(Config::CONFIG['bindir'],
                       Config::CONFIG['ruby_install_name'])

    ruby.gsub! File::SEPARATOR, File::ALT_SEPARATOR if File::ALT_SEPARATOR

    return ruby
  end

  ##
  # Return the name of the file with the tests for filename by finding
  # a +test_mapping+ that matches the file and executing the mapping's
  # proc.

  def test_files_for(filename)
    result = @test_mappings.find { |file_re, ignored| filename =~ file_re }

    p :test_file_for => [filename, result.first] if result and $DEBUG

    result = result.nil? ? [] : [result.last.call(filename, $~)].flatten

    output.puts "No tests matched #{filename}" if
      (options[:verbose] or $TESTING) and result.empty?

    result.sort.uniq.select { |f| known_files[f] }
  end

  ##
  # Sleep then look for files to test, until there are some.

  def wait_for_changes
    hook :waiting
    Kernel.sleep self.sleep until find_files_to_test
  end

  ############################################################
  # File Mappings:

  ##
  # Returns all known files in the codebase matching +regexp+.

  def files_matching regexp
    self.find_order.select { |k| k =~ regexp }
  end

  ##
  # Adds a file mapping, optionally prepending the mapping to the
  # front of the list if +prepend+ is true. +regexp+ should match a
  # file path in the codebase. +proc+ is passed a matched filename and
  # Regexp.last_match. +proc+ should return an array of tests to run.
  #
  # For example, if test_helper.rb is modified, rerun all tests:
  #
  #   at.add_mapping(/test_helper.rb/) do |f, _|
  #     at.files_matching(/^test.*rb$/)
  #   end

  def add_mapping(regexp, prepend = false, &proc)
    if prepend then
      @test_mappings.unshift [regexp, proc]
    else
      @test_mappings.push [regexp, proc]
    end
    nil
  end

  ##
  # Removed a file mapping matching +regexp+.

  def remove_mapping regexp
    @test_mappings.delete_if do |k,v|
      k == regexp
    end
    nil
  end

  ##
  # Clears all file mappings. This is DANGEROUS as it entirely
  # disables autotest. You must add at least one file mapping that
  # does a good job of rerunning appropriate tests.

  def clear_mappings
    @test_mappings.clear
    nil
  end

  ############################################################
  # Exceptions:

  ##
  # Adds +regexp+ to the list of exceptions for find_file. This must
  # be called _before_ the exceptions are compiled.

  def add_exception regexp
    raise "exceptions already compiled" if defined? @exceptions

    @exception_list << regexp
    nil
  end

  ##
  # Removes +regexp+ to the list of exceptions for find_file. This
  # must be called _before_ the exceptions are compiled.

  def remove_exception regexp
    raise "exceptions already compiled" if defined? @exceptions
    @exception_list.delete regexp
    nil
  end

  ##
  # Clears the list of exceptions for find_file. This must be called
  # _before_ the exceptions are compiled.

  def clear_exceptions
    raise "exceptions already compiled" if defined? @exceptions
    @exception_list.clear
    nil
  end

  ##
  # Return a compiled regexp of exceptions for find_files or nil if no
  # filtering should take place. This regexp is generated from
  # +exception_list+.

  def exceptions
    unless defined? @exceptions then
      if @exception_list.empty? then
        @exceptions = nil
      else
        @exceptions = Regexp.union(*@exception_list)
      end
    end

    @exceptions
  end

  ############################################################
  # Hooks:

  ##
  # Call the event hook named +name+, executing all registered hooks
  # until one returns true. Returns false if no hook handled the
  # event.

  def hook(name, *args)
    deprecated = {
      # none currently
    }

    if deprecated[name] and not HOOKS[name].empty? then
      warn "hook #{name} has been deprecated, use #{deprecated[name]}"
    end

    HOOKS[name].any? do |plugin|
      plugin[self, *args]
    end
  end

  ##
  # Add the supplied block to the available hooks, with the given
  # name.

  def self.add_hook(name, &block)
    HOOKS[name] << block
  end

  private

  # weird ruby 1.9 'feature': current path(path where autotest was called from) is not in $LOAD_PATH
  # see http://redmine.ruby-lang.org/issues/show/1733
  def self.with_current_path_in_load_path
    if RUBY_VERSION > "1.9"
      if not $LOAD_PATH.include?(File.expand_path('.')) and not $LOAD_PATH.include?('.')
        $LOAD_PATH << '.'
        current_path_was_added = true
      end
    end
    result = yield
    $LOAD_PATH.delete('.') if current_path_was_added
    result
  end

  #list of all available rubygem load paths
  def self.rubygem_load_paths
    begin
      require 'rubygems'
      Gem.latest_load_paths
    rescue LoadError
      []
    end
  end
end