Prevent error when all lines are blank in _strip_blank_lines.

dbieber · copybara-github · commit f01aad347632 · 2019-08-05T15:38:17.000-07:00
PiperOrigin-RevId: 261784747
Change-Id: I40ac24b553b2b4fa081de3fe0b1250472e1011a7
diff --git a/fire/docstrings.py b/fire/docstrings.py
@@ -212,7 +212,8 @@ def _strip_blank_lines(lines):
   """
   # Find the first non-blank line.
   start = 0
-  while lines and _is_blank(lines[start]):
+  num_lines = len(lines)
+  while lines and start < num_lines and _is_blank(lines[start]):
     start += 1
 
   lines = lines[start:]
