From 1eee03c8bdb6c0815b2eaecd8b68013f15bf9917 Mon Sep 17 00:00:00 2001
From: Raymond Julin <raymond.julin@gmail.com>
Date: Sun, 9 Aug 2020 23:34:14 +0200
Subject: [PATCH] Safeguard against a JS error when a non-existant entity is
 used

---
 package.json        | 1 -
 src/filterEntity.js | 3 +++
 src/index.js        | 2 +-
 3 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/package.json b/package.json
index 0428ad4..7216b8a 100644
--- a/package.json
+++ b/package.json
@@ -17,7 +17,6 @@
     "@babel/core": "^7.10.3",
     "@babel/register": "^7.10.3",
     "@rollup/plugin-commonjs": "^13.0.0",
-    "@ava/babel-preset-stage-4": "^4.0.0",
     "ava": "^3.9.0",
     "husky": "^4.2.5",
     "prettier": "^1.18.2",
diff --git a/src/filterEntity.js b/src/filterEntity.js
index 48a0eba..448bf77 100644
--- a/src/filterEntity.js
+++ b/src/filterEntity.js
@@ -38,6 +38,9 @@ function compareValue(expect, real) {
 // And the entire HASS state tree
 // this function will determine if the passed entity passes filtering rules or not
 function filterEntity(config, allStates) {
+  if (!allStates.hasOwnProperty(config.entity)) {
+    return false;
+  }
   if (config.when) {
     const { state: expect, entity = config.entity, attributes } =
       typeof config.when === "string" ? { state: config.when } : config.when;
diff --git a/src/index.js b/src/index.js
index de320f0..c28a088 100644
--- a/src/index.js
+++ b/src/index.js
@@ -97,7 +97,7 @@ class BannerCard extends LitElement {
     this._hass = hass;
 
     // Parse new state values for _entities_
-    this.entityValues = this.entities
+    this.entityValues = (this.entities || [])
       .filter(conf => filterEntity(conf, hass.states))
       .map(conf => this.parseEntity(conf));
   }