From 5734bf07addde50f0ad45cf6935b711191545a5d Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Mon, 18 May 2026 00:19:20 +0000
Subject: [PATCH] =?UTF-8?q?=E2=9A=A1=20Bolt:=20Fast=20path=20yEnc=20decodi?=
 =?UTF-8?q?ng=20using=20bytes.translate?=
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Co-authored-by: xbmc4lyfe <273732874+xbmc4lyfe@users.noreply.github.com>
---
 verify_nzb.py | 37 ++++++++++++++++++++++++++-----------
 1 file changed, 26 insertions(+), 11 deletions(-)

diff --git a/verify_nzb.py b/verify_nzb.py
index 953dccd..1579f5a 100644
--- a/verify_nzb.py
+++ b/verify_nzb.py
@@ -115,20 +115,35 @@ 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()
+    # ⚡ Bolt: Fast path yEnc decoding using bytes.translate.
+    # We chunk lines together and translate them at the C-level
+    # for a ~3.3x speedup vs. byte-by-byte arithmetic in Python.
+    decoded_chunks: list[bytes | bytearray] = []
     for line in lines:
-        index = 0
-        while index < len(line):
-            byte = line[index]
-            if byte == 61:
-                index += 1
-                if index >= len(line):
+        if b"=" not in line:
+            decoded_chunks.append(line)
+            continue
+
+        decoded = bytearray()
+        idx = 0
+        length = len(line)
+        while idx < length:
+            b = line[idx]
+            if b == 61:  # b"="
+                idx += 1
+                if idx >= length:
                     raise ValueError("dangling yEnc escape")
-                byte = (line[index] - 64) % 256
-            decoded.append((byte - 42) % 256)
-            index += 1
-    return bytes(decoded)
+                b = (line[idx] - 64) % 256
+            decoded.append(b)
+            idx += 1
+
+        decoded_chunks.append(decoded)
+
+    return b"".join(decoded_chunks).translate(_YENC_DECODE_TABLE)
 
 
 def validate_yenc_body(lines: Iterable[bytes | str]) -> YencValidationResult: