Added Florian Gross' latest version of Breakpointer and friends that …

…fixes a variaty of bugs #441 [Florian Gross]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@492 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/lib/binding_of_caller.rb

@@ -1,85 +1,83 @@
-begin
-  require 'simplecc'
-rescue LoadError
-  class Continuation #:nodoc:
-    def self.create(*args, &block)
-      cc = nil; result = callcc {|c| cc = c; block.call(cc) if block and args.empty?}
-      result ||= args
-      return *[cc, *result]
-    end
-  end
-end
-
-class Binding #:nodoc:
-  # This method returns the binding of the method that called your
-  # method. It will raise an Exception when you're not inside a method.
-  #
-  # It's used like this:
-  #   def inc_counter(amount = 1)
-  #     Binding.of_caller do |binding|
-  #       # Create a lambda that will increase the variable 'counter'
-  #       # in the caller of this method when called.
-  #       inc = eval("lambda { |arg| counter += arg }", binding)
-  #       # We can refer to amount from inside this block safely.
-  #       inc.call(amount)
-  #     end
-  #     # No other statements can go here. Put them inside the block.
-  #   end
-  #   counter = 0
-  #   2.times { inc_counter }
-  #   counter # => 2
-  #
-  # Binding.of_caller must be the last statement in the method.
-  # This means that you will have to put everything you want to
-  # do after the call to Binding.of_caller into the block of it.
-  # This should be no problem however, because Ruby has closures.
-  # If you don't do this an Exception will be raised. Because of
-  # the way that Binding.of_caller is implemented it has to be
-  # done this way.
-  def self.of_caller(&block)
-    old_critical = Thread.critical
-    Thread.critical = true
-    count = 0
-    cc, result, error, extra_data = Continuation.create(nil, nil)
-    error.call if error
-
-    tracer = lambda do |*args|
-      type, context, extra_data = args[0], args[4], args
-      if type == "return"
-        count += 1
-        # First this method and then calling one will return --
-        # the trace event of the second event gets the context
-        # of the method which called the method that called this
-        # method.
-        if count == 2
-          # It would be nice if we could restore the trace_func
-          # that was set before we swapped in our own one, but
-          # this is impossible without overloading set_trace_func
-          # in current Ruby.
-          set_trace_func(nil)
-          cc.call(eval("binding", context), nil, extra_data)
-        end
-      elsif type == "line" then
-        nil
-      elsif type == "c-return" and extra_data[3] == :set_trace_func then
-        nil
-      else
-        set_trace_func(nil)
-        error_msg = "Binding.of_caller used in non-method context or " +
-          "trailing statements of method using it aren't in the block."
-        cc.call(nil, lambda { raise(ArgumentError, error_msg) }, nil)
-      end
-    end
-
-    unless result
-      set_trace_func(tracer)
-      return nil
-    else
-      Thread.critical = old_critical
-      case block.arity
-        when 1 then yield(result)
-        else yield(result, extra_data)        
-      end
-    end
-  end
-end
+begin
+  require 'simplecc'
+rescue LoadError
+  class Continuation; end # :nodoc: # for RDoc
+  def Continuation.create(*args, &block) # :nodoc:
+    cc = nil; result = callcc {|c| cc = c; block.call(cc) if block and args.empty?}
+    result ||= args
+    return *[cc, *result]
+  end
+end
+
+class Binding; end # for RDoc
+# This method returns the binding of the method that called your
+# method. It will raise an Exception when you're not inside a method.
+#
+# It's used like this:
+#   def inc_counter(amount = 1)
+#     Binding.of_caller do |binding|
+#       # Create a lambda that will increase the variable 'counter'
+#       # in the caller of this method when called.
+#       inc = eval("lambda { |arg| counter += arg }", binding)
+#       # We can refer to amount from inside this block safely.
+#       inc.call(amount)
+#     end
+#     # No other statements can go here. Put them inside the block.
+#   end
+#   counter = 0
+#   2.times { inc_counter }
+#   counter # => 2
+#
+# Binding.of_caller must be the last statement in the method.
+# This means that you will have to put everything you want to
+# do after the call to Binding.of_caller into the block of it.
+# This should be no problem however, because Ruby has closures.
+# If you don't do this an Exception will be raised. Because of
+# the way that Binding.of_caller is implemented it has to be
+# done this way.
+def Binding.of_caller(&block)
+  old_critical = Thread.critical
+  Thread.critical = true
+  count = 0
+  cc, result, error, extra_data = Continuation.create(nil, nil)
+  error.call if error
+
+  tracer = lambda do |*args|
+    type, context, extra_data = args[0], args[4], args
+    if type == "return"
+      count += 1
+      # First this method and then calling one will return --
+      # the trace event of the second event gets the context
+      # of the method which called the method that called this
+      # method.
+      if count == 2
+        # It would be nice if we could restore the trace_func
+        # that was set before we swapped in our own one, but
+        # this is impossible without overloading set_trace_func
+        # in current Ruby.
+        set_trace_func(nil)
+        cc.call(eval("binding", context), nil, extra_data)
+      end
+    elsif type == "line" then
+      nil
+    elsif type == "c-return" and extra_data[3] == :set_trace_func then
+      nil
+    else
+      set_trace_func(nil)
+      error_msg = "Binding.of_caller used in non-method context or " +
+        "trailing statements of method using it aren't in the block."
+      cc.call(nil, lambda { raise(ArgumentError, error_msg) }, nil)
+    end
+  end
+
+  unless result
+    set_trace_func(tracer)
+    return nil
+  else
+    Thread.critical = old_critical
+    case block.arity
+      when 1 then yield(result)
+      else yield(result, extra_data)        
+    end
+  end
+end