Add bounds check to pickRandom nbItems (#128)

Co-authored-by: Robert Davidson <[email protected]>

Author: RobertJohnDavidson

src/methods/selecting/pickRandomItems.ts

@@ -10,6 +10,13 @@ export default function pickRandomItems(
     seed?: number,
     verbose = false
 ): SimpleDataItem[] {
+    if (nbItems <= 0) {
+        throw new Error("You must choose a number of items greater than 0")
+    }
+    if (nbItems > data.length) {
+        nbItems = data.length
+    }
+
     const shuffle = seed ? shuffler(randomLcg(seed)) : shuffler(randomLcg())
     const randomizedData = shuffle(data).slice(0, nbItems)
     const nbRemoved = data.length - nbItems

test/unit/methods/selecting/pickRandomItems.test.ts

@@ -27,3 +27,15 @@ describe("pickRandomItems", function () {
         ])
     })
 })
+
+describe("pickRandomItems", function () {
+    it("should return an error because a negative value is given", function () {
+        const data = [
+            { key1: 0, key2: 2 },
+            { key1: 1, key2: 2 },
+            { key1: 2, key2: 4 },
+            { key1: 2, key2: 6 },
+        ]
+        assert.throws(() => pickRandomItems(data, -1), Error)
+    })
+})