feat: add uniqueArray helper function

1 files changed, 29 insertions, 0 deletions

diff --git a/lib/helpers.js b/lib/helpers.js
index 68e895e7..4ecdaab3 100644
--- a/lib/helpers.js
+++ b/lib/helpers.js
@@ -216,6 +216,35 @@ var Helpers = function (faker) {
   };
 
   /**
+   * takes an array of strings or function that returns a string
+   * and outputs a unique array of strings based on that source
+   * @example uniqueArray(faker.random.word, 50)
+   * @example uniqueArray(faker.definitions.name.first_name, 6)
+   * @example uniqueArray(["Hello", "World", "Goodbye"], 2)
+   * @method faker.helpers.uniqueArray
+   * @param {string[] | function => string} source
+   * @param {number} length
+   * @returns {string[]}
+  */
+  self.uniqueArray = function(source, length) {
+    if (Array.isArray(source)) {
+      const set = new Set(source);
+      const array = Array.from(set);
+      return faker.helpers.shuffle(array).splice(0, length);
+    }
+    const set = new Set();
+    try {
+      if (typeof source === "function") {
+        while (set.size < length) {
+          set.add(source());
+        }
+      }
+    } finally {
+      return Array.from(set);
+    }
+  };
+
+  /**
    * mustache
    *
    * @method faker.helpers.mustache