From 5964efa262fa03ea9866953d734f04be97d0b7c4 Mon Sep 17 00:00:00 2001
From: Mark Sagi-Kazar <mark.sagikazar@gmail.com>
Date: Mon, 24 Jun 2024 18:14:40 +0200
Subject: [PATCH] fix: do not allow overwriting the mapstructure output

Signed-off-by: Mark Sagi-Kazar <mark.sagikazar@gmail.com>
---
 viper.go | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/viper.go b/viper.go
index 6f472ec..d96e1d9 100644
--- a/viper.go
+++ b/viper.go
@@ -949,7 +949,6 @@ func (v *Viper) decodeStructKeys(input any, opts ...DecoderConfigOption) ([]stri
 func defaultDecoderConfig(output any, opts ...DecoderConfigOption) *mapstructure.DecoderConfig {
 	c := &mapstructure.DecoderConfig{
 		Metadata:         nil,
-		Result:           output,
 		WeaklyTypedInput: true,
 		DecodeHook: mapstructure.ComposeDecodeHookFunc(
 			mapstructure.StringToTimeDurationHookFunc(),
@@ -957,9 +956,14 @@ func defaultDecoderConfig(output any, opts ...DecoderConfigOption) *mapstructure
 			stringToWeakSliceHookFunc(","),
 		),
 	}
+
 	for _, opt := range opts {
 		opt(c)
 	}
+
+	// Do not allow overwriting the output
+	c.Result = output
+
 	return c
 }