PayoutDetailsForm: helper functions to normalize US phone numbers

src/forms/PayoutDetailsForm/normalizePhoneNumberUS.js

@@ -0,0 +1,32 @@
+// Normalize US phone number
+// Stripe requires phone numbers for US companies and their owners
+
+/**
+ * Format a phone number: this is just an override for default formatting.
+ */
+export const format = value => (!value ? '' : value);
+
+/**
+ * Parser that strips non-digit characters away from a phone number
+ * string unless they are dashes in correct places.
+ *
+ * Returns the given US phone number in format: 202-555-0102
+ */
+export const parse = value => {
+  if (!value) {
+    return value;
+  }
+
+  const phoneNumber =
+    typeof value === 'string' && value.indexOf('+1') >= 0 ? value.substring(2) : value;
+
+  const onlyNums = phoneNumber.replace(/[^\d]/g, '');
+
+  if (onlyNums.length <= 3) {
+    return onlyNums;
+  } else if (onlyNums.length <= 7) {
+    return `${onlyNums.slice(0, 3)}-${onlyNums.slice(3, 7)}`;
+  } else {
+    return `${onlyNums.slice(0, 3)}-${onlyNums.slice(3, 6)}-${onlyNums.slice(6, 10)}`;
+  }
+};