resolves 'Gizzmo subtree doesn't reach grandparents'

lib/gizzard/commands.rb

@@ -65,23 +65,23 @@ def run
       @roots = []
       argv.each do |arg|
         @id = ShardId.parse(arg)
-        @roots << up(@id)
+        @roots += roots_of(@id)
       end
       @roots.uniq.each do |root|
         output root.to_unix
         down(root, 1)
       end
     end
 
-    def up(id)
+    def roots_of(id)
       links = service.list_upward_links(id)
       if links.empty?
-        id
+        [id]
       else
-        links.map { |link| link.up_id }.find { |up_id| up(up_id) }
+        links.map { |link| roots_of(link.up_id) }.flatten
       end
     end
-
+    
     def down(id, depth = 0)
       service.list_downward_links(id).map do |link|
         printable = "  " * depth + link.down_id.to_unix

test/expected/deep.txt

@@ -0,0 +1,10 @@
+localhost/table_deep_repl_0
+  localhost/table_deep_repl_1
+    localhost/table_deep_repl_2
+      localhost/table_deep_repl_3
+        localhost/table_deep_repl_4
+          localhost/table_deep_repl_5
+            localhost/table_deep_repl_6
+              localhost/table_deep_repl_7
+                localhost/table_deep_repl_8
+                  localhost/table_deep_repl_9

test/expected/subtree-info.txt

@@ -29,5 +29,3 @@ localhost/table_b_8	com.twitter.service.flock.edges.SqlShard	unbusy
 localhost/table_repl_9	com.twitter.service.flock.edges.ReplicatingShard	unbusy
 localhost/table_a_9	com.twitter.service.flock.edges.SqlShard	unbusy
 localhost/table_b_9	com.twitter.service.flock.edges.SqlShard	unbusy
-localhost/replicating_table_b_0	com.twitter.service.flock.edges.ReplicatingShard	unbusy
-localhost/table_b_0	com.twitter.service.flock.edges.SqlShard	unbusy

test/expected/subtree.txt

@@ -10,8 +10,6 @@ localhost/table_repl_1
 localhost/table_repl_2
   localhost/table_a_2
   localhost/table_b_2
-localhost/blocked_table_a_3
-  localhost/table_a_3
 localhost/table_repl_4
   localhost/table_a_4
   localhost/table_b_4

test/test.sh

@@ -62,3 +62,14 @@ g links localhost/table_b_0 | expect empty-file.txt
 g wrap com.twitter.gizzard.shards.BlockedShard localhost/table_a_3
 g find -hlocalhost | xargs ../bin/gizzmo -Cconfig.yaml subtree 2>&1 | expect subtree.txt
 g find -hlocalhost | ../bin/gizzmo -Cconfig.yaml subtree 2>&1 | expect subtree.txt
+
+# test a deep tree
+g create localhost "table_deep_repl_0" com.twitter.service.flock.edges.ReplicatingShard
+for i in {1..9}
+do
+  last=$((i-1))
+  g create localhost "table_deep_repl_$i" com.twitter.service.flock.edges.ReplicatingShard
+  g addlink "localhost/table_deep_repl_$last" "localhost/table_deep_repl_$i" 2
+done
+
+g subtree localhost/table_deep_repl_5 | expect deep.txt