fix: form data with same key send only last one (#2606)

Co-authored-by: Andrew Bastin <andrewbastin.k@gmail.com>

packages/hoppscotch-app/helpers/functional/record.ts

@@ -1,3 +1,11 @@
+/**
+ * Converts an array of key-value tuples (for e.g ["key", "value"]), into a record.
+ * (for eg. output -> { "key": "value" })
+ * NOTE: This function will discard duplicate key occurances and only keep the last occurance. If you do not want that behaviour,
+ * use `tupleWithSamesKeysToRecord`.
+ * @param tuples Array of tuples ([key, value])
+ * @returns A record with value corresponding to the last occurance of that key
+ */
 export const tupleToRecord = <
   KeyType extends string | number | symbol,
   ValueType
@@ -5,5 +13,32 @@ export const tupleToRecord = <
   tuples: [KeyType, ValueType][]
 ): Record<KeyType, ValueType> =>
   tuples.length > 0
-    ? (Object.assign as any)(...tuples.map(([key, val]) => ({ [key]: val })))
+    ? (Object.assign as any)(...tuples.map(([key, val]) => ({ [key]: val }))) // This is technically valid, but we have no way of telling TypeScript it is valid. Hence the assertion
     : {}
+
+/**
+ * Converts an array of key-value tuples (for e.g ["key", "value"]), into a record.
+ * (for eg. output -> { "key": ["value"] })
+ * NOTE: If you do not want the array as values (because of duplicate keys) and want to instead get the last occurance, use `tupleToRecord`
+ * @param tuples Array of tuples ([key, value])
+ * @returns A Record with values being arrays corresponding to each key occurance
+ */
+export const tupleWithSameKeysToRecord = <
+  KeyType extends string | number | symbol,
+  ValueType
+>(
+  tuples: [KeyType, ValueType][]
+): Record<KeyType, ValueType[]> => {
+  // By the end of the function we do ensure this typing, this can't be infered now though, hence the assertion
+  const out = {} as Record<KeyType, ValueType[]>
+
+  for (const [key, value] of tuples) {
+    if (!out[key]) {
+      out[key] = [value]
+    } else {
+      out[key].push(value)
+    }
+  }
+
+  return out
+}