Deduplicate code in scripts/helpers and test/helpers/iterate (#4895)

Co-authored-by: ernestognw <ernestognw@gmail.com>

scripts/helpers.js

@@ -1,31 +1,10 @@
-function chunk(array, size = 1) {
-  return Array.range(Math.ceil(array.length / size)).map(i => array.slice(i * size, i * size + size));
-}
-
-function range(start, stop = undefined, step = 1) {
-  if (!stop) {
-    stop = start;
-    start = 0;
-  }
-  return start < stop ? Array.from({ length: Math.ceil((stop - start) / step) }, (_, i) => start + i * step) : [];
-}
-
-function unique(array, op = x => x) {
-  return array.filter((obj, i) => array.findIndex(entry => op(obj) === op(entry)) === i);
-}
-
-function zip(...args) {
-  return Array.from({ length: Math.max(...args.map(arg => arg.length)) }, (_, i) => args.map(arg => arg[i]));
-}
-
-function capitalize(str) {
-  return str.charAt(0).toUpperCase() + str.slice(1);
-}
+const iterate = require('../test/helpers/iterate');
 
 module.exports = {
-  chunk,
-  range,
-  unique,
-  zip,
-  capitalize,
+  // Capitalize the first char of a string
+  // Example: capitalize('uint256') → 'Uint256'
+  capitalize: str => str.charAt(0).toUpperCase() + str.slice(1),
+
+  // Iterate tools for the test helpers
+  ...iterate,
 };