Merge pull request #25 from cddr/iresolve-index

Add index? method to IResolve

Author: dgrnbrg

src/hitchhiker/tree/core.clj

@@ -14,6 +14,7 @@
 (defprotocol IResolve
   "All nodes must implement this protocol. It's includes the minimal functionality
    necessary to avoid resolving nodes unless strictly necessary."
+  (index? [_] "Returns true if this is an index node")
   (last-key [_] "Returns the rightmost key of the node")
   (dirty? [_] "Returns true if this should be flushed")
   ;;TODO resolve should be instrumented
@@ -103,6 +104,7 @@
 
 (defrecord IndexNode [children storage-addr op-buf cfg]
   IResolve
+  (index? [this] true)
   (dirty? [this] (not (realized? storage-addr)))
   (resolve [this] this) ;;TODO this is a hack for testing
   (last-key [this]
@@ -213,6 +215,7 @@
 
 (defrecord DataNode [children storage-addr cfg]
   IResolve
+  (index? [this] false)
   (resolve [this] this) ;;TODO this is a hack for testing
   (dirty? [this] (not (realized? storage-addr)))
   (last-key [this]

test/hitchhiker/tree/core_test.clj

@@ -21,7 +21,13 @@
           data2 (data-node (->Config 3 3 2) (sorted-map 6 6 7 7 8 8 9 9 10 10))
           root (->IndexNode [data1 data2] (promise) [] (->Config 3 3 2))]
       (is (= (map first (lookup-fwd-iter root 4)) (range 4 11)))
-      (is (= (map first (lookup-fwd-iter root 0)) (range 1 11))))))
+      (is (= (map first (lookup-fwd-iter root 0)) (range 1 11)))))
+
+  (testing "index nodes identified as such"
+    (let [data (data-node (->Config 3 3 2) (sorted-map 1 1))
+          root (->IndexNode [data] (promise) [] (->Config 3 3 2))]
+      (is (index? root))
+      (is (not (index? data))))))
 
 (defn insert-helper
   [t k]