Split debrew up to faciliate test isolation

We want to be able to test the raise functionality without
monkey-patching #raise on every object in the system, which is one of
the side effects of loading debrew.rb.

4 files changed, 123 insertions, 0 deletions

diff --git a/Library/Homebrew/debrew/exception.rb b/Library/Homebrew/debrew/exception.rb
new file mode 100644
index 000000000..da8e56dae
--- /dev/null
+++ b/Library/Homebrew/debrew/exception.rb
@@ -0,0 +1,7 @@
+class Exception
+  attr_accessor :continuation
+
+  def restart(&block)
+    continuation.call block
+  end
+end
diff --git a/Library/Homebrew/debrew/irb.rb b/Library/Homebrew/debrew/irb.rb
new file mode 100644
index 000000000..c81e3cf4b
--- /dev/null
+++ b/Library/Homebrew/debrew/irb.rb
@@ -0,0 +1,33 @@
+require 'irb'
+
+module IRB
+  @setup_done = false
+
+  def IRB.start_within(binding)
+    unless @setup_done
+      # make IRB ignore our command line arguments
+      saved_args = ARGV.shift(ARGV.size)
+      IRB.setup(nil)
+      ARGV.concat(saved_args)
+      @setup_done = true
+    end
+
+    workspace = WorkSpace.new(binding)
+    irb = Irb.new(workspace)
+
+    @CONF[:IRB_RC].call(irb.context) if @CONF[:IRB_RC]
+    @CONF[:MAIN_CONTEXT] = irb.context
+
+    trap("SIGINT") do
+      irb.signal_handle
+    end
+
+    begin
+      catch(:IRB_EXIT) do
+        irb.eval_input
+      end
+    ensure
+      irb_at_exit
+    end
+  end
+end
diff --git a/Library/Homebrew/debrew/menu.rb b/Library/Homebrew/debrew/menu.rb
new file mode 100644
index 000000000..c59c500b8
--- /dev/null
+++ b/Library/Homebrew/debrew/menu.rb
@@ -0,0 +1,39 @@
+class Menu
+  attr_accessor :prompt
+  attr_accessor :entries
+
+  def initialize
+    @entries = []
+  end
+
+  def choice(name, &action)
+    entries << { :name => name, :action => action }
+  end
+end
+
+def choose
+  menu = Menu.new
+  yield menu
+
+  choice = nil
+  while choice.nil?
+    menu.entries.each_with_index do |entry, i|
+      puts "#{i+1}. #{entry[:name]}"
+    end
+    print menu.prompt unless menu.prompt.nil?
+    reply = $stdin.gets.chomp
+
+    i = reply.to_i
+    if i > 0
+      choice = menu.entries[i-1]
+    else
+      possible = menu.entries.find_all {|e| e[:name].to_s.start_with? reply }
+      case possible.size
+        when 0 then puts "No such option"
+        when 1 then choice = possible.first
+        else puts "Multiple options match: #{possible.map{|e| e[:name]}.join(' ')}"
+      end
+    end
+  end
+  choice[:action].call
+end
diff --git a/Library/Homebrew/debrew/raise_plus.rb b/Library/Homebrew/debrew/raise_plus.rb
new file mode 100644
index 000000000..74f59aa46
--- /dev/null
+++ b/Library/Homebrew/debrew/raise_plus.rb
@@ -0,0 +1,44 @@
+require 'continuation' if RUBY_VERSION.to_f >= 1.9
+
+class Exception
+  attr_accessor :continuation
+
+  def restart(&block)
+    continuation.call block
+  end
+end
+
+module RaisePlus
+  alias :original_raise :raise
+
+  def raise(*args)
+    exception = case
+                when args.size == 0
+                  $!.nil? ? RuntimeError.exception : $!
+                when args.size == 1 && args[0].is_a?(String)
+                  RuntimeError.exception(args[0])
+                when args.size == 2 && args[0].is_a?(Exception)
+                  args[0].exception(args[1])
+                when args[0].is_a?(Class) && args[0].ancestors.include?(Exception)
+                  args[0].exception(args[1])
+                else
+                  args[0]
+                end
+
+    # passing something other than a String or Exception is illegal, but if someone does it anyway,
+    # that object won't have backtrace or continuation methods. in that case, let's pass it on to
+    # the original raise, which will reject it
+    return super exception unless exception.is_a?(Exception)
+
+    # keep original backtrace if reraising
+    exception.set_backtrace(args.size >= 3 ? args[2] : caller) if exception.backtrace.nil?
+
+    blk = callcc do |cc|
+      exception.continuation = cc
+      super exception
+    end
+    blk.call unless blk.nil?
+  end
+
+  alias :fail :raise
+end