kit.rb in cli-kit-3.0.0.pre

- old
+ new
@@ -1,7 +1,56 @@
 require 'cli/ui'
+require 'cli/kit/ruby_backports/enumerable'
 
 module CLI
   module Kit
-    autoload :System, 'cli/kit/system'
+    autoload :BaseCommand,     'cli/kit/base_command'
+    autoload :CommandRegistry, 'cli/kit/command_registry'
+    autoload :Config,          'cli/kit/config'
+    autoload :ErrorHandler,    'cli/kit/error_handler'
+    autoload :Executor,        'cli/kit/executor'
+    autoload :Ini,             'cli/kit/ini'
+    autoload :Levenshtein,     'cli/kit/levenshtein'
+    autoload :Resolver,        'cli/kit/resolver'
+    autoload :System,          'cli/kit/system'
+
+    EXIT_FAILURE_BUT_NOT_BUG = 30
+    EXIT_BUG                 = 1
+    EXIT_SUCCESS             = 0
+
+    # Abort, Bug, AbortSilent, and BugSilent are four ways of immediately bailing
+    # on command-line execution when an unrecoverable error occurs.
+    #
+    # Note that these don't inherit from StandardError, and so are not caught by
+    # a bare `rescue => e`.
+    #
+    # * Abort prints its message in red and exits 1;
+    # * Bug additionally submits the exception to Bugsnag;
+    # * AbortSilent and BugSilent do the same as above, but do not print
+    #     messages before exiting.
+    #
+    # Treat these like panic() in Go:
+    #   * Don't rescue them. Use a different Exception class if you plan to recover;
+    #   * Provide a useful message, since it will be presented in brief to the
+    #       user, and will be useful for debugging.
+    #   * Avoid using it if it does actually make sense to recover from an error.
+    #
+    # Additionally:
+    #   * Do not subclass these.
+    #   * Only use AbortSilent or BugSilent if you prefer to print a more
+    #       contextualized error than Abort or Bug would present to the user.
+    #   * In general, don't attach a message to AbortSilent or BugSilent.
+    #   * Never raise GenericAbort directly.
+    #   * Think carefully about whether Abort or Bug is more appropriate. Is this
+    #       a bug in the tool? Or is it just user error, transient network
+    #       failure, etc.?
+    #   * One case where it's ok to rescue (cli-kit internals or tests aside):
+    #       1. rescue Abort or Bug
+    #       2. Print a contextualized error message
+    #       3. Re-raise AbortSilent or BugSilent respectively.
+    GenericAbort = Class.new(Exception)
+    Abort        = Class.new(GenericAbort)
+    Bug          = Class.new(GenericAbort)
+    BugSilent    = Class.new(GenericAbort)
+    AbortSilent  = Class.new(GenericAbort)
   end
 end