From 7bcd13785caeda541f1ef979768849946dda905a Mon Sep 17 00:00:00 2001
From: Roman Gonzalez <romanandreg@gmail.com>
Date: Thu, 22 Nov 2012 22:55:31 +0000
Subject: [PATCH] CLJS-426 Fix on subvec inconsitent behavior when using
 invalid ranges

---
 src/cljs/cljs/core.cljs       |   19 ++++++++++++++-----
 test/cljs/cljs/core_test.cljs |   17 ++++++++++++-----
 2 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/src/cljs/cljs/core.cljs b/src/cljs/cljs/core.cljs
index 561746f..a62e3e4 100644
--- a/src/cljs/cljs/core.cljs
+++ b/src/cljs/cljs/core.cljs
@@ -3184,7 +3184,7 @@ reduces them without incurring seq initialization"
     (pr-str this))
 
   IWithMeta
-  (-with-meta [coll meta] (Subvec. meta v start end __hash))
+  (-with-meta [coll meta] (build-subvec meta v start end __hash))
 
   IMeta
   (-meta [coll] meta)
@@ -3195,11 +3195,11 @@ reduces them without incurring seq initialization"
   (-pop [coll]
     (if (== start end)
       (throw (js/Error. "Can't pop empty vector"))
-      (Subvec. meta v start (dec end) nil)))
+      (build-subvec meta v start (dec end) nil)))
 
   ICollection
   (-conj [coll o]
-    (Subvec. meta (-assoc-n v end o) start (inc end) nil))
+    (build-subvec meta (-assoc-n v end o) start (inc end) nil))
 
   IEmptyableCollection
   (-empty [coll] (with-meta cljs.core.Vector/EMPTY meta))
@@ -3236,7 +3236,7 @@ reduces them without incurring seq initialization"
   IAssociative
   (-assoc [coll key val]
     (let [v-pos (+ start key)]
-      (Subvec. meta (-assoc v v-pos val)
+      (build-subvec meta (-assoc v v-pos val)
                start (max end (inc v-pos))
                nil)))
 
@@ -3255,6 +3255,15 @@ reduces them without incurring seq initialization"
   (-invoke [coll k not-found]
     (-lookup coll k not-found)))
 
+(defn- build-subvec [meta v start end ^:mutable __hash]
+  (let [c (count v)]
+       (when (or (neg? start)
+                 (neg? end)
+                 (> start c)
+                 (> end c))
+         (throw (js/Error. "Index out of bounds")))
+       (Subvec. meta v start end __hash)))
+
 (defn subvec
   "Returns a persistent vector of the items in vector from
   start (inclusive) to end (exclusive).  If end is not supplied,
@@ -3264,7 +3273,7 @@ reduces them without incurring seq initialization"
   ([v start]
      (subvec v start (count v)))
   ([v start end]
-     (Subvec. nil v start end nil)))
+     (build-subvec nil v start end nil)))
 
 (defn- tv-ensure-editable [edit node]
   (if (identical? edit (.-edit node))
diff --git a/test/cljs/cljs/core_test.cljs b/test/cljs/cljs/core_test.cljs
index bf425d0..99ef397 100644
--- a/test/cljs/cljs/core_test.cljs
+++ b/test/cljs/cljs/core_test.cljs
@@ -1007,13 +1007,14 @@
     (assert (= 94 (peek stack2))))
 
   ;; subvec
-  (let [v (vec (range 10))
-        s (subvec v 2 8)]
+  (let [v1 (vec (range 10))
+        v2 (vec (range 5))
+        s (subvec v1 2 8)]
     (assert (= s
-               (-> v
+               (-> v1
                    (subvec 2)
                    (subvec 0 6))
-               (->> v
+               (->> v1
                     (drop 2)
                     (take 6))))
     (assert (= 6 (count s)))
@@ -1024,7 +1025,13 @@
                (conj s 1)))
     (assert (= 27 (reduce + s)))
     (assert (= s (vec s))) ; pour into plain vector
-    (let [m {:x 1}] (assert (= m (meta (with-meta s m))))))
+    (let [m {:x 1}] (assert (= m (meta (with-meta s m)))))
+    ;; go outside ranges
+    (assert (= :fail (try (subvec v2 0 6) (catch js/Error e :fail))))
+    (assert (= :fail (try (subvec v2 6 10) (catch js/Error e :fail))))
+    (assert (= :fail (try (subvec v2 6 10) (catch js/Error e :fail))))
+    (assert (= :fail (try (subvec v2 3 6) (catch js/Error e :fail))))
+    )
 
   ;; TransientVector
   (let [v1 (vec (range 15 48))
-- 
1.7.9.5