Class: Autotest

Inherits:
Object
  • Object
show all
Defined in:
lib/autotest.rb,
lib/autotest/rails.rb,
lib/autotest/preload.rb

Overview

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_.*<impl-name>.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.

Defined Under Namespace

Modules: AutoUpdate, Bundler, Fixtures, Isolate, Migrate, Once, Preload, RCov, Rails, Restart, Timestamp

Constant Summary collapse

TOPDIR =
Dir.pwd + "/"
T0 =
Time.at 0
ALL_HOOKS =
[ :all_good, :died, :initialize, :post_initialize,
:interrupt, :quit, :ran_command, :reset,
:run_command, :updated, :waiting ]
HOOKS =
Hash.new { |h,k| h[k] = [] }
WINDOZE =
/mswin|mingw/ =~ RbConfig::CONFIG['host_os']
SEP =
WINDOZE ? '&' : ';'

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(options) ⇒ Autotest

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


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# File 'lib/autotest.rb', line 179

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

  self.options           = options
  self.extra_class_map   = {}
  self.extra_files       = []
  self.failures          = Hash.new { |h,k| h[k] = Hash.new { |h2,k2| h2[k2] = [] } }
  self.files_to_test     = new_hash_of_arrays
  reset_find_order
  self.libs              = %w[. lib test].join(File::PATH_SEPARATOR)
  self.output            = $stderr
  self.prefix            = nil
  self.sleep             = 1
  self.test_mappings     = []
  self.test_prefix       = "gem 'minitest'"
  self.testlib           = "minitest/autorun" # TODO: rename

  self.find_directories  = ['.']

  # 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 (ruby & rails styles)
  self.add_mapping(/^test.*\/(test_.*|.*_test)\.rb$/) do |filename, _|
    filename
  end

  default_configs = [File.expand_path('~/.autotest'), './.autotest']
  configs = options[:rc] || default_configs

  configs.each do |f|
    load f if File.exist? f
  end
end

Instance Attribute Details

#extra_class_mapObject

Returns the value of attribute extra_class_map


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# File 'lib/autotest.rb', line 156

def extra_class_map
  @extra_class_map
end

#extra_filesObject

Returns the value of attribute extra_files


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# File 'lib/autotest.rb', line 157

def extra_files
  @extra_files
end

#failuresObject

Returns the value of attribute failures


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# File 'lib/autotest.rb', line 158

def failures
  @failures
end

#files_to_testObject

TODO: remove in favor of failures?


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# File 'lib/autotest.rb', line 159

def files_to_test
  @files_to_test
end

#find_directoriesObject

Returns the value of attribute find_directories


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# File 'lib/autotest.rb', line 160

def find_directories
  @find_directories
end

#find_orderObject

Returns the value of attribute find_order


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# File 'lib/autotest.rb', line 161

def find_order
  @find_order
end

#interruptedObject

Returns the value of attribute interrupted


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# File 'lib/autotest.rb', line 162

def interrupted
  @interrupted
end

#known_filesObject

Lazy accessor for the known_files hash.


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# File 'lib/autotest.rb', line 459

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

#last_mtimeObject

Returns the value of attribute last_mtime


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# File 'lib/autotest.rb', line 163

def last_mtime
  @last_mtime
end

#libsObject

Returns the value of attribute libs


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# File 'lib/autotest.rb', line 164

def libs
  @libs
end

#optionsObject

Returns the value of attribute options


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# File 'lib/autotest.rb', line 69

def options
  @options
end

#outputObject

Returns the value of attribute output


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# File 'lib/autotest.rb', line 165

def output
  @output
end

#prefixObject

Returns the value of attribute prefix


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# File 'lib/autotest.rb', line 166

def prefix
  @prefix
end

#sleepObject

Returns the value of attribute sleep


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# File 'lib/autotest.rb', line 167

def sleep
  @sleep
end

#taintedObject Also known as: tainted?

Returns the value of attribute tainted


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# File 'lib/autotest.rb', line 168

def tainted
  @tainted
end

#test_mappingsObject

Returns the value of attribute test_mappings


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# File 'lib/autotest.rb', line 169

def test_mappings
  @test_mappings
end

#test_prefixObject

Returns the value of attribute test_prefix


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# File 'lib/autotest.rb', line 171

def test_prefix
  @test_prefix
end

#testlibObject

Returns the value of attribute testlib


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# File 'lib/autotest.rb', line 170

def testlib
  @testlib
end

#wants_to_quitObject

Returns the value of attribute wants_to_quit


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# File 'lib/autotest.rb', line 172

def wants_to_quit
  @wants_to_quit
end

Class Method Details

.add_hook(name, &block) ⇒ Object

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


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# File 'lib/autotest.rb', line 732

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

.parse_options(args = ARGV) ⇒ Object


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# File 'lib/autotest.rb', line 76

def self.parse_options args = ARGV
  require 'optparse'
  options = {
    :args => args.dup
  }

  OptionParser.new do |opts|
    opts.banner = <<-BANNER.gsub(/^        /, '')
      Continuous testing for your ruby app.

        Autotest automatically tests code that has changed. It assumes
        the code is in lib, and tests are in test/test_*.rb. 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.

      Usage:
          autotest [options]
    BANNER

    opts.on "-d", "--debug", "Debug mode, for reporting bugs." do
      require "pp"
      options[:debug] = true
    end

    opts.on "-f", "--focus", "Focus mode, only run named tests." do
      options[:focus] = true
    end

    opts.on "-v", "--verbose", "Be annoyingly verbose (debugs .autotest)." do
      options[:verbose] = true
    end

    opts.on "-q", "--quiet", "Be quiet." do
      options[:quiet] = true
    end

    opts.on("-r", "--rc CONF", String, "Override path to config file") do |o|
      options[:rc] = Array(o)
    end

    opts.on("-w", "--warnings", "Turn on ruby warnings") do
      $-w = true
    end

    opts.on "-h", "--help", "Show this." do
      puts opts
      exit 1
    end
  end.parse! args

  options
end

.run(args = ARGV) ⇒ Object

Initialize and run the system.


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# File 'lib/autotest.rb', line 134

def self.run args = ARGV
  expander = PathExpander.new args, "**/*.rb"
  files = expander.process

  autotest = new parse_options args

  if autotest.options[:debug] then
    puts
    puts "options:"
    puts
    pp autotest.options
    puts "files:"
    puts
    pp files
    puts
  end

  autotest.extra_files = files
  autotest.run
end

Instance Method Details

#add_exception(regexp) ⇒ Object

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


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# File 'lib/autotest.rb', line 658

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

  @exception_list << regexp
  nil
end

#add_mapping(regexp, prepend = false, &proc) ⇒ Object

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

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# File 'lib/autotest.rb', line 622

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

#add_sigint_handlerObject

Installs a sigint handler.


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# File 'lib/autotest.rb', line 323

def add_sigint_handler
  trap 'INT' do
    Process.kill "KILL", @child if @child

    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

#add_sigquit_handlerObject

Installs a sigquit handler


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# File 'lib/autotest.rb', line 343

def add_sigquit_handler
  trap 'QUIT' do
    restart
  end
end

#all_goodObject

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


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# File 'lib/autotest.rb', line 372

def all_good
  failures.empty?
end

#class_mapObject


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# File 'lib/autotest.rb', line 235

def class_map
  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
  class_map
end

#clear_exceptionsObject

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


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# File 'lib/autotest.rb', line 679

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

#clear_mappingsObject

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.


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# File 'lib/autotest.rb', line 646

def clear_mappings
  @test_mappings.clear
  nil
end

#debugObject


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# File 'lib/autotest.rb', line 220

def debug
  find_files_to_test

  puts "Known test files:"
  puts
  pp files_to_test.keys.sort

  class_map = self.class_map

  puts
  puts "Known class map:"
  puts
  pp class_map
end

#exceptionsObject

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


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# File 'lib/autotest.rb', line 690

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

  @exceptions
end

#files_matching(regexp) ⇒ Object

Returns all known files in the codebase matching regexp.


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# File 'lib/autotest.rb', line 606

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

#find_filesObject

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


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# File 'lib/autotest.rb', line 394

def find_files
  result = {}

  targets = if options[:focus] then
              self.extra_files
            else
              self.find_directories + self.extra_files
            end

  reset_find_order

  targets.each do |target|
    order = []
    Find.find target do |f|
      Find.prune if f =~ self.exceptions
      Find.prune if f =~ /^\.\/tmp/    # temp dir, used by isolate

      next unless File.file? f
      next if f =~ /(swp|~|rej|orig)$/ # temporary/patch files
      next if f =~ /(,v)$/             # RCS 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

  result
end

#find_files_to_test(files = find_files) ⇒ Object

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.


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# File 'lib/autotest.rb', line 434

def find_files_to_test files = find_files
  updated = files.select { |filename, mtime| self.last_mtime < mtime }

  # nothing to update or initially run
  unless updated.empty? || self.last_mtime.to_i == 0 then
    p updated if options[:verbose]

    hook :updated, updated
  end

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

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

#get_to_greenObject

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


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# File 'lib/autotest.rb', line 290

def get_to_green
  begin
    run_tests
    wait_for_changes unless all_good
  end until all_good
end

#hook(name, *args) ⇒ Object

Call the event hook named name, passing in optional args depending on the hook itself.

Returns false if no hook handled the event.

Hook Writers!

This executes all registered hooks until one returns truthy. Pay attention to the return value of your block!


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# File 'lib/autotest.rb', line 716

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? { |plugin| plugin[self, *args] }
end

#make_test_cmd(files_to_test) ⇒ Object

Generate the commands to test the supplied files


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# File 'lib/autotest.rb', line 469

def make_test_cmd files_to_test
  if options[:debug] then
    puts "Files to test:"
    puts
    pp files_to_test
    puts
  end

  cmds = []
  full, partial = reorder(failures).partition { |k,v| v.empty? }

  unless full.empty? then
    classes = full.map {|k,v| k}.flatten.uniq
    classes.unshift testlib
    classes = classes.join " "
    cmds << "#{ruby_cmd} -e \"#{test_prefix}; %w[#{classes}].each { |f| require f }\" -- --server #{$$}"
  end

  unless partial.empty? then
    files = partial.map(&:first).sort # no longer a hash because of partition
    files.select! { |path| File.file? path } # filter out (eval) and the like
    re = []

    partial.each do |path, klasses|
      klasses.each do |klass,methods|
        re << /#{klass}##{Regexp.union(methods)}/
      end
    end

    loader = "%w[#{files.join " "}].each do |f| load f; end"
    re = Regexp.union(re).to_s.gsub(/-mix/, "").gsub(/'/, ".")

    cmds << "#{ruby_cmd} -e '#{loader}' -- --server #{$$} -n '/#{re}/'"
  end

  cmds.join "#{SEP} "
end

#minitest_result(file, klass, method, fails, assertions, time) ⇒ Object


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# File 'lib/autotest.rb', line 743

def minitest_result file, klass, method, fails, assertions, time
  fails.reject! { |fail| Minitest::Skip === fail }

  unless fails.empty?
    self.tainted = true
    self.failures[file][klass] << method
  end
end

#minitest_startObject

Server Methods:


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# File 'lib/autotest.rb', line 739

def minitest_start
  self.failures.clear
end

#new_hash_of_arraysObject


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# File 'lib/autotest.rb', line 507

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

#old_path_to_classnameObject

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


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# File 'lib/autotest/rails.rb', line 57

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

#old_run_testsObject

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


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# File 'lib/autotest/preload.rb', line 27

def run_tests
  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?

  hook :run_command, cmd

  puts cmd unless options[:quiet]

  system cmd

  hook :ran_command
end

#path_to_classname(s) ⇒ Object

Convert the pathname s to the name of class.


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# File 'lib/autotest.rb', line 380

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

#remove_exception(regexp) ⇒ Object

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


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# File 'lib/autotest.rb', line 669

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

#remove_mapping(regexp) ⇒ Object

Removed a file mapping matching regexp.


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# File 'lib/autotest.rb', line 634

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

#reorder(files_to_test) ⇒ Object


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# File 'lib/autotest.rb', line 511

def reorder files_to_test
  max = files_to_test.size
  files_to_test.sort_by { |k,v| rand max }
end

#rerun_all_testsObject

Rerun the tests from cold (reset state)


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# File 'lib/autotest.rb', line 519

def rerun_all_tests
  reset
  run_tests

  hook :all_good if all_good
end

#resetObject

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


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# File 'lib/autotest.rb', line 530

def reset
  self.files_to_test.clear
  reset_find_order
  self.failures.clear

  self.interrupted   = false
  self.last_mtime    = T0
  self.tainted       = false
  self.wants_to_quit = false

  hook :reset
end

#reset_find_orderObject


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# File 'lib/autotest.rb', line 543

def reset_find_order
  self.find_order = []
  self.known_files = nil
end

#restartObject


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# File 'lib/autotest.rb', line 349

def restart
  Minitest::Server.stop

  Process.kill "KILL", @child if @child

  cmd = [$0, *options[:args]]

  index = $LOAD_PATH.index RbConfig::CONFIG["sitelibdir"]

  if index then
    extra = $LOAD_PATH[0...index]
    cmd = [Gem.ruby, "-I", extra.join(":")] + cmd
  end

  puts cmd.join(" ") if options[:verbose]

  exec(*cmd)
end

#rubyObject

Determine and return the path of the ruby executable.


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# File 'lib/autotest.rb', line 551

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

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

  return ruby
end

#ruby_cmdObject

Returns the base of the ruby command.


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# File 'lib/autotest.rb', line 564

def ruby_cmd
  "#{prefix}#{ruby} -I#{libs}"
end

#runObject

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


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# File 'lib/autotest.rb', line 247

def run
  hook :initialize
  hook :post_initialize

  require "minitest/server"
  Minitest::Server.run self

  reset
  add_sigint_handler

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

  self.debug if options[:debug]

  loop do
    begin # ^c handler
      get_to_green
      if tainted? and not options[:no_full_after_failed] then
        rerun_all_tests
      else
        hook :all_good
      end
      wait_for_changes
    rescue Interrupt
      break if wants_to_quit
      reset
    end
  end
  hook :quit
  puts
rescue Exception => err
  hook(:died, err) or (
    warn "Unhandled exception: #{err}"
    warn err.backtrace.join("\n  ")
    warn "Quitting"
  )
ensure
  Minitest::Server.stop
end

#run_testsObject

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


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# File 'lib/autotest.rb', line 300

def run_tests
  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?

  hook :run_command, cmd

  puts cmd unless options[:quiet]

  system cmd

  hook :ran_command
end

#test_files_for(filename) ⇒ Object

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.


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# File 'lib/autotest.rb', line 573

def test_files_for filename
  result = []

  self.test_mappings.each do |file_re, proc|
    if filename =~ file_re then
      result = [proc.call(filename, $~)].
        flatten.sort.uniq.select { |f| known_files[f] }
      break unless result.empty?
    end
  end

  p :test_file_for => [filename, result.first] if result and options[:debug]

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

  return result
end

#wait_for_changesObject

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


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# File 'lib/autotest.rb', line 595

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