From a531041f3e1c6ae195485bbace3750630646633a Mon Sep 17 00:00:00 2001
From: Peter Dekkers <425971+PeterDekkers@users.noreply.github.com>
Date: Sat, 25 May 2024 09:48:29 +1200
Subject: [PATCH] Ensure that scipy/numpy output is JSON-serializable

---
 Lib/fontTools/varLib/interpolatableHelpers.py | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Lib/fontTools/varLib/interpolatableHelpers.py b/Lib/fontTools/varLib/interpolatableHelpers.py
index 2a3540fff..f71b32afd 100644
--- a/Lib/fontTools/varLib/interpolatableHelpers.py
+++ b/Lib/fontTools/varLib/interpolatableHelpers.py
@@ -143,6 +143,9 @@ def min_cost_perfect_bipartite_matching_scipy(G):
     n = len(G)
     rows, cols = linear_sum_assignment(G)
     assert (rows == list(range(n))).all()
+    # Convert numpy array and integer to Python types,
+    # to ensure that this is JSON-serializable.
+    cols = list(int(e) for e in cols)
     return list(cols), matching_cost(G, cols)