Allow placeholder images for products and line items without images

framework/spree/utils/validate-placeholder-image-url.ts

@@ -0,0 +1,15 @@
+const validatePlaceholderImageUrl = (
+  placeholderUrlOrFalse: unknown
+): string | false => {
+  if (!placeholderUrlOrFalse || placeholderUrlOrFalse === 'false') {
+    return false
+  }
+
+  if (typeof placeholderUrlOrFalse === 'string') {
+    return placeholderUrlOrFalse
+  }
+
+  throw new TypeError('placeholderUrlOrFalse must be a string or falsy.')
+}
+
+export default validatePlaceholderImageUrl