feat(stdlib): Add fromArray to Queue module (#1932)

Co-authored-by: Blaine Bublitz <blaine.bublitz@gmail.com>

Author: spotandjake

compiler/test/stdlib/queue.test.gr

@@ -126,6 +126,15 @@ let queue4 = Queue.copy(queue3)
 Queue.pop(queue4)
 assert Queue.toArray(queue4) == [> 2, 3]
 
+// Queue.fromArray
+let qa1 = Queue.makeSized(8)
+Queue.push(1, qa1)
+Queue.push(2, qa1)
+Queue.push(3, qa1)
+Queue.push(4, qa1)
+assert Queue.fromArray([> 1, 2, 3, 4]) == qa1
+assert Queue.fromArray([>]) == Queue.makeSized(16)
+
 module Immutable {
   from Queue use { module Immutable as Queue }
 

stdlib/queue.gr

@@ -201,6 +201,30 @@ provide let toArray = queue => {
   }, arr)
 }
 
+/**
+ * Creates a queue from an array.
+ *
+ * @param arr: The array to convert
+ * @returns A queue containing all values from the array
+ *
+ * @since v0.6.0
+ */
+provide let fromArray = arr => {
+  let size = Array.length(arr)
+  let contents = if (size == 0) {
+    Array.make(16, None)
+  } else {
+    Array.init(size * 2, i => {
+      if (i < size) {
+        Some(arr[i])
+      } else {
+        None
+      }
+    })
+  }
+  { size, array: contents, headIndex: 0, tailIndex: size }
+}
+
 /**
  * An immutable queue implementation.
  */

stdlib/queue.md

@@ -269,6 +269,31 @@ Returns:
 |----|-----------|
 |`Array<a>`|An array containing all values from the given queue|
 
+### Queue.**fromArray**
+
+<details disabled>
+<summary tabindex="-1">Added in <code>next</code></summary>
+No other changes yet.
+</details>
+
+```grain
+fromArray : (arr: Array<a>) => Queue<a>
+```
+
+Creates a queue from an array.
+
+Parameters:
+
+|param|type|description|
+|-----|----|-----------|
+|`arr`|`Array<a>`|The array to convert|
+
+Returns:
+
+|type|description|
+|----|-----------|
+|`Queue<a>`|A queue containing all values from the array|
+
 ## Queue.Immutable
 
 An immutable queue implementation.