adding default folder, addressing nits

Author: cpeddecord

checkout/javascript/cart-checkout-validation/.gitignore renamed to checkout/javascript/cart-checkout-validation/default/.gitignore

@@ -0,0 +1,44 @@
+{%- if flavor contains "vanilla-js" -%}
+// @ts-check
+
+/**
+ * @typedef {import("../generated/api").InputQuery} InputQuery
+ * @typedef {import("../generated/api").FunctionResult} FunctionResult
+ */
+
+export default /**
+ * @param {InputQuery} input
+ * @returns {FunctionResult}
+ */
+(input) => {
+  const errors = input.cart.lines
+    .filter(({ quantity }) => quantity > 1)
+    .map(() => ({
+      localizedMessage: "Not possible to order more than one of each",
+      target: "cart",
+    }));
+
+  return {
+    errors
+  }
+};
+{%- elsif flavor contains "typescript" -%}
+import {
+  InputQuery,
+  FunctionResult,
+  FunctionError,
+} from "../generated/api";
+
+export default (input: InputQuery): FunctionResult => {
+  const errors: FunctionError[] = input.cart.lines
+    .filter(({ quantity }) => quantity > 1)
+    .map(() => ({
+      localizedMessage: "Not possible to order more than one of each",
+      target: "cart",
+    }));
+
+  return {
+    errors
+  }
+};
+{%- endif -%}