Refactor Time library to use valueBefore/valueAfter (#4555)

Co-authored-by: Francisco <fg@frang.io>

test/helpers/iterate.js

@@ -0,0 +1,16 @@
+// Map values in an object
+const mapValues = (obj, fn) => Object.fromEntries(Object.entries(obj).map(([k, v]) => [k, fn(v)]));
+
+// Array of number or bigint
+const max = (...values) => values.slice(1).reduce((x, y) => (x > y ? x : y), values[0]);
+const min = (...values) => values.slice(1).reduce((x, y) => (x < y ? x : y), values[0]);
+
+// Cartesian product of a list of arrays
+const product = (...arrays) => arrays.reduce((a, b) => a.flatMap(ai => b.map(bi => [...ai, bi])), [[]]);
+
+module.exports = {
+  mapValues,
+  max,
+  min,
+  product,
+};