Use int.from_bytes instead of implementing the conversion ourselves.

anntzer · anntzer · commit 907f0b75b374 · 2023-11-08T20:30:15.000+01:00
int.from_bytes has been around since Python 3.2.
diff --git a/lib/matplotlib/dviread.py b/lib/matplotlib/dviread.py
@@ -392,16 +392,10 @@ def _read(self):
 
     def _arg(self, nbytes, signed=False):
         """
-        Read and return an integer argument *nbytes* long.
+        Read and return a big-endian integer *nbytes* long.
         Signedness is determined by the *signed* keyword.
         """
-        buf = self.file.read(nbytes)
-        value = buf[0]
-        if signed and value >= 0x80:
-            value = value - 0x100
-        for b in buf[1:]:
-            value = 0x100*value + b
-        return value
+        return int.from_bytes(self.file.read(nbytes), "big", signed=signed)
 
     @_dispatch(min=0, max=127, state=_dvistate.inpage)
     def _set_char_immediate(self, char):
