Tests for getDeviceAccountSettings()

webpack/resources/__tests__/selectors_test.ts

@@ -227,3 +227,17 @@ describe("maybeFindPlantById()", () => {
     expect(result).toBeUndefined();
   });
 });
+
+describe("getDeviceAccountSettings", () => {
+  it("crashes if < 1", () => {
+    pending();
+  });
+
+  it("crashes if > 1", () => {
+    pending();
+  });
+
+  it("returns exactly one device", () => {
+    pending();
+  });
+});

webpack/resources/selectors.ts

@@ -30,7 +30,7 @@ import {
   TaggedDevice,
   TaggedWebAppConfig
 } from "./tagged_resources";
-import { CowardlyDictionary, betterCompact, sortResourcesById } from "../util";
+import { CowardlyDictionary, betterCompact, sortResourcesById, bail } from "../util";
 import { isNumber } from "util";
 type StringMap = CowardlyDictionary<string>;
 
@@ -451,24 +451,16 @@ export function maybeGetDevice(index: ResourceIndex): TaggedDevice | undefined {
   return (dev && dev.kind === "Device") ?
     dev : undefined;
 }
-export function getDeviceAccountSettings(index: ResourceIndex) {
+export function getDeviceAccountSettings(index: ResourceIndex): TaggedDevice {
   const list = index.byKind.Device;
-  const uuid = list[0];
-  const device = index.references[uuid || -1];
-  if (list.length === 0) {
-    throw new Error(`Tried to load device before it was loaded.`);
-  }
-
-  if (list.length > 1) {
-    throw new Error(`PROBLEM: Expected getDeviceAccountSettings() to return
-    exactly 1 device. Found multiple devices.`);
-  }
-
-  if (device && device.kind === "Device") {
-    sanityCheck(device);
-    return device;
-  } else {
-    throw new Error("Malformed device resource");
+  const uuid = list[0] || "_";
+  const device = index.references[uuid];
+  switch (list.length) {
+    case 0: return bail(`Tried to load device before it was loaded.`);
+    case 1: return (device && device.kind === "Device" && sanityCheck(device))
+      ? device
+      : bail("Malformed device!");
+    default: return bail("Found more than 1 device");
   }
 }