Fix depsolving logic to handle depless services

Services with no dependencies no longer cause failure

1 files changed, 13 insertions, 5 deletions

diff --git a/state.rb b/state.rb
index 6912b49..9bc8e34 100644
--- a/state.rb
+++ b/state.rb
@@ -195,11 +195,19 @@ class State
 		active_states = @@states.select{ |x| x.active }
 		candidates = @depends.map{ |d| active_states.select{ |s| d.match s } }
 		return nil if candidates.include? []
-		candidates[0].product(*candidates[1..-1]).map{ |x| x.to_set } \
-			.select{ |x| x.inject(true){ |st, y| st and y.rooted_in x } } \
-			.reject do |dset|
-				active_states.select{ |x| x.is_a? self and x.deps == dset }.size > 0
-			end.each{ |x| self.new x }
+
+		unless candidates == []
+			candidates = candidates[0].product(*candidates[1..-1]).map{ |x| x.to_set } \
+				.select{ |x| x.size == 0 or x.inject(true){ |st, y| st and y.rooted_in x } }
+		else
+			candidates = [Set.new]
+		end
+
+		candidates.reject! do |dset|
+			active_states.select{ |x| x.is_a? self and x.deps == dset }.size > 0
+		end
+
+		candidates.each{ |x| self.new x }
 	end
 
 	# Depsolve all state classes. This method is not defined in subclasses of