fix(stdlib): Properly resize empty Queue on push (#1865)

Author: spotandjake

compiler/test/stdlib/queue.test.gr

@@ -47,6 +47,11 @@ assert Queue.pop(queue) == Some(1)
 assert Queue.pop(queue) == Some(2)
 assert Queue.pop(queue) == Some(3)
 assert Queue.pop(queue) == None
+let queue = Queue.makeSized(0)
+Queue.push(0, queue)
+let queue2 = Queue.makeSized(1)
+Queue.push(0, queue2)
+assert queue == queue2
 
 // test that the "circular" behavior of the circular queue works as expected
 let queue = Queue.makeSized(4)

stdlib/queue.gr

@@ -94,7 +94,9 @@ provide let peek = queue => {
 provide let push = (value, queue) => {
   let arrLen = Array.length(queue.array)
   // expand the array if needed
-  if (queue.size == arrLen) {
+  if (arrLen == 0) {
+    queue.array = Array.make(1, None)
+  } else if (queue.size == arrLen) {
     let newArray = Array.make(arrLen * 2, None)
 
     newArray[0] = queue.array[queue.headIndex]