From 348e2f4ed1ea10722346c1fb5e76abe12a408368 Mon Sep 17 00:00:00 2001
From: jan <jan@orange.mpxd.net>
Date: Wed, 30 Mar 2022 23:57:31 -0700
Subject: [PATCH] Raise an exception if a layer is both a metal and a via

---
 snarl/utils.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/snarl/utils.py b/snarl/utils.py
index 339c6be..82747ef 100644
--- a/snarl/utils.py
+++ b/snarl/utils.py
@@ -14,6 +14,8 @@ def connectivity2layers(
         if via is not None:
             via_layers.add(via)
 
-    # TODO verify no overlap between metal and via layer specifications
+    both = metal_layers.intersection(via_layers)
+    if both:
+        raise Exception(f'The following layers are both vias and metals!? {both}')
 
     return metal_layers, via_layers