fetcher.rb in rubyfocus-0.5.1

- old
+ new

@@ -36,10 +36,28 @@
 	# Returns the contents of a given patch
 	def patch(filename)
 		raise RuntimeError, "Method Fetcher#patch called for abstract class Fetcher."
 	end
 
+	# Returns the latest patch
+	def head
+		@head ||= patches.sort.last
+	end
+
+	# Can you reach head from the given ID?
+	def can_reach_head_from?(id)
+		patch_array = patches.select{ |p| p.from_ids.include?(id) }
+		until patch_array.empty?
+			p = patch_array.first
+			return true if p == self.head
+
+			next_patches = patches.select{ |np| np.from_ids.include? p.to_id }
+			patch_array = patch_array[1..-1] + next_patches
+		end
+		return false
+	end
+
 	#---------------------------------------
 	# Patching methods
 
 	# Update the document as far as we can
 	def update_full(document)
@@ -63,10 +81,10 @@
 
 	# Collect the next patch to the document. If more than one patch can be applied,
 	# apply the latest one.
 	def next_patch(document)
 		all_possible_patches = self.patches.select{ |patch| patch.can_patch?(document) }
-		return all_possible_patches.sort_by(&:time).last
+		return all_possible_patches.sort.first
 	end
 
 
 	#---------------------------------------
 	# Serialisation info
\ No newline at end of file