From: Robert Jordens <jordens@gmail.com>
Date: Sun, 17 Aug 2014 20:56:31 +0000 (-0600)
Subject: Signal.__getitem__: raise TypeError and IndexError when appropriate
X-Git-Tag: 24jan2021_ls180~2099^2~319
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=6036fffef2f8be0afb6b82203a4dd56489dbd178;p=litex.git

Signal.__getitem__: raise TypeError and IndexError when appropriate
---

diff --git a/migen/fhdl/structure.py b/migen/fhdl/structure.py
index 3edc2860..ba84dd85 100644
--- a/migen/fhdl/structure.py
+++ b/migen/fhdl/structure.py
@@ -81,17 +81,20 @@ class Value(HUID):
 	def __getitem__(self, key):
 		from migen.fhdl.bitcontainer import flen
 
+		n = flen(self)
 		if isinstance(key, int):
+			if key >= n:
+				raise IndexError
 			if key < 0:
-				key += flen(self)
+				key += n
 			return _Slice(self, key, key+1)
 		elif isinstance(key, slice):
-			start, stop, step = key.indices(flen(self))
+			start, stop, step = key.indices(n)
 			if step != 1:
 				return Cat(self[i] for i in range(start, stop, step))
 			return _Slice(self, start, stop)
 		else:
-			raise KeyError
+			raise TypeError
 	
 	def eq(self, r):
 		"""Assignment