SF #726446: raise ValueError if width <= 0.

diff --git a/Lib/textwrap.py b/Lib/textwrap.py
index 03fcbc053e9cbb5f9d8a9b0b21da51f862b4065c..fdb95d71637ad482e2e77ea3a3ddb5e69bf20e43 100644 (file)
--- a/Lib/textwrap.py
+++ b/Lib/textwrap.py
@@ -197,6 +197,8 @@ class TextWrapper:
         lines, but apart from that whitespace is preserved.
         """
         lines = []
+        if self.width <= 0:
+            raise ValueError("invalid width %r (must be > 0)" % self.width)
 
         while chunks: