scripts: codemap[d3].py: Added -e/--error-on-recursion

Might as well, since we already need to find this to calculate stack
info.

I've been considering adding -z/--depth to these scripts as well, but
that would require quite a bit more work. It's probably not worth the
added complexity/headache. Depth termination would need to happen on the
javascript side, and we'd still need cycle detection anyways.

But an error code is easy to add.

scripts/codemap.py

@@ -1247,6 +1247,10 @@ def main_(f, paths, *,
         line = canvas.draw(row)
         f.writeln(line)
 
+    if (args.get('error_on_recursion')
+            and mt.isinf(totals.get('stack', 0))):
+        sys.exit(2)
+
 
 def main(paths, *,
         height=None,
@@ -1496,6 +1500,10 @@ if __name__ == "__main__":
             '--no-label',
             action='store_true',
             help="Don't render any labels.")
+    parser.add_argument(
+            '-e', '--error-on-recursion',
+            action='store_true',
+            help="Error if any functions are recursive.")
     parser.add_argument(
             '--code-path',
             type=lambda x: x.split(),