CLJS-3306: subvecs must implement IAssociative -contains-key?

Author: mfikes

src/main/cljs/cljs/core.cljs

@@ -5943,6 +5943,10 @@ reduces them without incurring seq initialization"
     (if (number? key)
       (-assoc-n coll key val)
       (throw (js/Error. "Subvec's key for assoc must be a number."))))
+  (-contains-key? [coll key]
+    (if (integer? key)
+      (and (<= 0 key) (< key (- end start)))
+      false))
 
   IFind
   (-find [coll n]

src/test/cljs/cljs/core_test.cljs

@@ -1844,3 +1844,13 @@
     (is (false? (contains? nonempty-extended :c)))
     (is (true?  (contains? nonempty-extended :y)))
     (is (false? (contains? nonempty-extended :z)))))
+
+(deftest test-cljs-3306
+  (let [sv (subvec [0 1 2 3 4] 2 4)]
+    (is (true?  (contains? sv 0)))
+    (is (false? (contains? sv 0.5)))
+    (is (true?  (contains? sv 1)))
+    (is (false? (contains? sv 1.5)))
+    (is (false? (contains? sv :kw))))
+  (let [sv (subvec [0 1 2 3 4] 2 2)]
+    (is (false? (contains? sv 0)))))