Add tests

Author: cmdcolin

packages/core/src/util/jexl.ts

@@ -8,7 +8,9 @@ export default function JexlF(/* config?: any*/) {
   // ones passed in
 
   // below are core functions
-  j.addFunction('get', (feature: Feature, data: string) => feature?.get(data))
+  j.addFunction('get', (feature: Feature | undefined, data: string) =>
+    feature?.get(data),
+  )
   j.addFunction('parent', (feature: Feature) => feature.parent?.())
 
   j.addFunction('id', (feature: Feature) => feature.id())

plugins/linear-genome-view/src/BaseLinearDisplay/util.ts

@@ -1,4 +1,4 @@
-import { mergeIntervals, SimpleFeature } from '@jbrowse/core/util'
+import { SimpleFeature, mergeIntervals } from '@jbrowse/core/util'
 
 import type RpcManager from '@jbrowse/core/rpc/RpcManager'
 import type { Feature } from '@jbrowse/core/util'