From 7c03bc6ba7af39439e96e87a6082cb8791b8dfcc Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Wed, 10 Jun 2026 00:32:32 +0000
Subject: [PATCH] Optimize yEnc decoding using bytes.translate and bytes.find

Co-authored-by: xbmc4lyfe <273732874+xbmc4lyfe@users.noreply.github.com>
---
 verify_nzb.py | 32 +++++++++++++++++++++++---------
 1 file changed, 23 insertions(+), 9 deletions(-)

diff --git a/verify_nzb.py b/verify_nzb.py
index 953dccd..4a28b36 100644
--- a/verify_nzb.py
+++ b/verify_nzb.py
@@ -115,19 +115,33 @@ def _parse_yenc_attrs(line: bytes) -> dict[str, str]:
     return attrs
 
 
+_YENC_DECODE_TABLE = bytes((i - 42) % 256 for i in range(256))
+
+
 def _decode_yenc_lines(lines: Iterable[bytes]) -> bytes:
     decoded = bytearray()
     for line in lines:
+        if b"=" not in line:
+            decoded.extend(line.translate(_YENC_DECODE_TABLE))
+            continue
+
         index = 0
-        while index < len(line):
-            byte = line[index]
-            if byte == 61:
-                index += 1
-                if index >= len(line):
-                    raise ValueError("dangling yEnc escape")
-                byte = (line[index] - 64) % 256
-            decoded.append((byte - 42) % 256)
-            index += 1
+        length = len(line)
+        while index < length:
+            pos = line.find(b"=", index)
+            if pos == -1:
+                decoded.extend(line[index:].translate(_YENC_DECODE_TABLE))
+                break
+
+            if pos > index:
+                decoded.extend(line[index:pos].translate(_YENC_DECODE_TABLE))
+
+            if pos + 1 >= length:
+                raise ValueError("dangling yEnc escape")
+
+            decoded.append((line[pos+1] - 106) % 256)
+            index = pos + 2
+
     return bytes(decoded)