From 5202755231cb95e66434da194ea79078de2313ec Mon Sep 17 00:00:00 2001
From: James Hadfield <hadfield.james@gmail.com>
Date: Fri, 19 Mar 2021 09:14:31 +1300
Subject: [PATCH] Ensure metadata.display_defaults exists

A bug was introduced in PR #1280 where datasets which did not
define `metadata.display_defaults` would crash, as the code assumed
its existence. This property is optional in the dataset
JSON.

This commit ensures `display_defaults` exists in redux state after
a dataset is loaded, thus allowing code to rely on its presence.
This was preferred to checking for `display_defaults` in (all) the
relevant sections of code, now and in future.

(Using TypeScript, or expanding our smoke tests, would be approaches
to avoiding these kinds of bugs in future.)
---
 CHANGELOG.md                       | 4 ++--
 src/actions/recomputeReduxState.js | 2 ++
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 80dcdd563..9c753f744 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,9 +2,9 @@
 title: Changelog
 ---
 
-## version 2.24.0 - 2021/03/17
-
+* [bugfix] Fixes a bug introduced in v2.24.0 where certain datasets wouldn't load
 
+## version 2.24.0 - 2021/03/17
 
 * Frequencies are no longer normalized when the data is lacking.
 See [PR 1278](https://github.com/nextstrain/auspice/pull/1278) for more.
diff --git a/src/actions/recomputeReduxState.js b/src/actions/recomputeReduxState.js
index d479ff0b4..a1fc7a42b 100644
--- a/src/actions/recomputeReduxState.js
+++ b/src/actions/recomputeReduxState.js
@@ -241,6 +241,8 @@ const modifyStateViaMetadata = (state, metadata) => {
         }
       }
     }
+  } else {
+    metadata.displayDefaults = {}; // allows code to rely on `displayDefaults` existing
   }
 
   if (metadata.panels) {