Improve FormData.get

Author: nojaf

src/FetchAPI/FormData.res

@@ -31,13 +31,13 @@ external delete: (formData, string) => unit = "delete"
 [Read more on MDN](https://developer.mozilla.org/docs/Web/API/FormData/get)
 */
 @send
-external get: (formData, string) => file = "get"
+external get: (formData, string) => string = "get"
 
 /**
 [Read more on MDN](https://developer.mozilla.org/docs/Web/API/FormData/get)
 */
 @send
-external get2: (formData, string) => string = "get"
+external getFile: (formData, string) => file = "get"
 
 /**
 [Read more on MDN](https://developer.mozilla.org/docs/Web/API/FormData/getAll)

tests/FetchAPI/FormData__test.js

@@ -0,0 +1,7 @@
+/* This works when your form has an id of "myForm" */
+@scope(("document", "forms"))
+external myForm: DOMAPI.htmlFormElement = "myForm"
+
+let formData = FormData.make(~form=myForm)
+let phone = formData->FormData.get("phone")
+let image = formData->FormData.getFile("image")