practracker: handle empty files.

Previously practracker would fail on a file with no lines.

practracker: handle empty files.
Previously practracker would fail on a file with no lines.
03040903 · Nick Mathewson · 3a296457 · 03040903
Commit 03040903 authored Sep 02, 2019 by Nick Mathewson 🥄
--- a/scripts/maint/practracker/metrics.py
+++ b/scripts/maint/practracker/metrics.py
@@ -8,6 +8,7 @@ import re

 def get_file_len(f):
    """Get file length of file"""
+    i = -1
    for i, l in enumerate(f):
        pass
    return i + 1