From 3b66a68f198b0774dc4d3b3baa5be36552928471 Mon Sep 17 00:00:00 2001
From: Loic Huder <loic.huder@esrf.fr>
Date: Fri, 30 Apr 2021 11:50:11 +0200
Subject: [PATCH] Jsonize NaN and Infinity as strings

---
 jupyterlab_hdf/tests/test_data.py | 8 ++++++++
 jupyterlab_hdf/util.py            | 6 ++++++
 2 files changed, 14 insertions(+)

diff --git a/jupyterlab_hdf/tests/test_data.py b/jupyterlab_hdf/tests/test_data.py
index 146503d..6c63d89 100644
--- a/jupyterlab_hdf/tests/test_data.py
+++ b/jupyterlab_hdf/tests/test_data.py
@@ -22,6 +22,7 @@ def setUp(self):
             h5file["complex"] = COMPLEX
             h5file["scalar"] = SCALAR
             h5file["empty"] = h5py.Empty(">f8")
+            h5file["NaNs"] = [np.NaN, np.inf, np.NINF, 0]
 
     def test_oneD_dataset(self):
         response = self.tester.get(["data", "test_file.h5"], params={"uri": "/oneD_dataset"})
@@ -88,3 +89,10 @@ def test_empty_dataset(self):
         assert response.status_code == 200
         payload = response.json()
         assert payload is None
+
+    def test_dataset_with_NaNs(self):
+        response = self.tester.get(["data", "test_file.h5"], params={"uri": "/NaNs"})
+
+        assert response.status_code == 200
+        payload = response.json()
+        assert payload == ["NaN", "Infinity", "-Infinity", 0]
diff --git a/jupyterlab_hdf/util.py b/jupyterlab_hdf/util.py
index df2272e..01c6c6e 100644
--- a/jupyterlab_hdf/util.py
+++ b/jupyterlab_hdf/util.py
@@ -329,6 +329,12 @@ def jsonize(v):
         return [v.real, v.imag]
     if isinstance(v, h5py.Empty):
         return None
+    if isinstance(v, float) and np.isnan(v):
+        return "NaN"
+    if isinstance(v, float) and np.isposinf(v):
+        return "Infinity"
+    if isinstance(v, float) and np.isneginf(v):
+        return "-Infinity"
     return v