From cbdda631dbd68765203d1843f217f47c6e0c5c48 Mon Sep 17 00:00:00 2001
From: Andreas Rumpf <rumpf_a@web.de>
Date: Sun, 20 Sep 2020 00:05:41 +0200
Subject: [PATCH] base64: fixes the error message for an invalid base64 input
 character [backport:1.2]

---
 lib/pure/base64.nim | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/pure/base64.nim b/lib/pure/base64.nim
index 9495c4d56a..40c9af9056 100644
--- a/lib/pure/base64.nim
+++ b/lib/pure/base64.nim
@@ -230,11 +230,11 @@ proc decode*(s: string): string =
 
   template inputChar(x: untyped) =
     let x = int decodeTable[ord(s[inputIndex])]
-    inc inputIndex
     if x == invalidChar:
       raise newException(ValueError,
         "Invalid base64 format character `" & s[inputIndex] &
         "` (ord " & $s[inputIndex].ord & ") at location " & $inputIndex & ".")
+    inc inputIndex
 
   template outputChar(x: untyped) =
     result[outputIndex] = char(x and 255)