CLJS-2012: Find on PHM with nil entry always returns nil entry

Author: thomasmulvaney

src/main/cljs/cljs/core.cljs

@@ -7412,8 +7412,9 @@ reduces them without incurring seq initialization"
 
   IFind
   (-find [coll k]
-    (if has-nil?
-      [nil nil-val]
+    (if (nil? k)
+      (when has-nil?
+        [nil nil-val])
       (.inode-find root 0 (hash k) k nil)))
 
   IMap

src/test/cljs/cljs/collections_test.cljs

@@ -640,7 +640,15 @@
       (is (= v v'))
       (is (= metadata (meta k'))))
     (let [map (hash-map nil :foo)]
-      (is (= (find map nil) [nil :foo]))))
+      (is (= (find map nil) [nil :foo])))
+    (let [metadata {:a 1}
+          k [1 2 3]
+          v 1
+          map (hash-map (with-meta k metadata) v nil 2)
+          [k' v'] (find map k)]
+      (is (= k k'))
+      (is (= v v'))
+      (is (= metadata (meta k')))))
   (testing "PersistentTreeMap"
     (let [metadata {:a 1}
           k [1 2 3]