From 0fb11403623c615f1236ada08e27dfd4edc3f71e Mon Sep 17 00:00:00 2001
From: Pedro Durek <pedro_hmd@hotmail.com>
Date: Wed, 9 Dec 2020 15:27:39 -0600
Subject: [PATCH] Fix issue which was defaulting TFunctionResult for t function
 (#1217)

---
 src/ts4.1/index.d.ts | 34 ++++++++++++++++++----------------
 1 file changed, 18 insertions(+), 16 deletions(-)

diff --git a/src/ts4.1/index.d.ts b/src/ts4.1/index.d.ts
index 9d50c81d4..a68710c2b 100644
--- a/src/ts4.1/index.d.ts
+++ b/src/ts4.1/index.d.ts
@@ -84,30 +84,32 @@ export type TFuncKey<N, T = Resources> = N extends (keyof T)[]
   ? Normalize<T[N]>
   : string;
 
-export type TFuncReturn<N, P, T = Resources> = N extends (keyof T)[]
-  ? NormalizeMultiReturn<T, P>
+export type TFuncReturn<N, TKeys, TDefaultResult, T = Resources> = [keyof Resources] extends [never]
+  ? TDefaultResult
+  : N extends (keyof T)[]
+  ? NormalizeMultiReturn<T, TKeys>
   : N extends keyof T
-  ? NormalizeReturn<T[N], P>
-  : TFunctionResult;
+  ? NormalizeReturn<T[N], TKeys>
+  : string;
 
 export interface TFunction<N extends Namespace = DefaultNamespace> {
   <
-    K extends TFuncKey<N> | TemplateStringsArray,
-    R extends TFuncReturn<N, K>,
-    I extends object = StringMap
+    TKeys extends TFuncKey<N> | TemplateStringsArray,
+    TDefaultResult extends TFunctionResult = string,
+    TInterpolationMap extends object = StringMap
   >(
-    key: K | K[],
-    options?: TOptions<I> | string,
-  ): R;
+    key: TKeys | TKeys[],
+    options?: TOptions<TInterpolationMap> | string,
+  ): TFuncReturn<N, TKeys, TDefaultResult>;
   <
-    K extends TFuncKey<N> | TemplateStringsArray,
-    R extends TFuncReturn<N, K>,
-    I extends object = StringMap
+    TKeys extends TFuncKey<N> | TemplateStringsArray,
+    TDefaultResult extends TFunctionResult = string,
+    TInterpolationMap extends object = StringMap
   >(
-    key: K | K[],
+    key: TKeys | TKeys[],
     defaultValue?: string,
-    options?: TOptions<I> | string,
-  ): R;
+    options?: TOptions<TInterpolationMap> | string,
+  ): TFuncReturn<N, TKeys, TDefaultResult>;
 }
 
 export interface TransProps<