extracts merge function into a helper module

app/engine/RowingEngine.test.js

@@ -9,7 +9,7 @@ import loglevel from 'loglevel'
 import rowerProfiles from '../../config/rowerProfiles.js'
 import { createRowingEngine } from './RowingEngine.js'
 import { replayRowingSession } from '../tools/RowingRecorder.js'
-import { deepMerge } from '../tools/ConfigManager.js'
+import { deepMerge } from '../tools/Helper.js'
 
 const log = loglevel.getLogger('RowingEngine.test')
 log.setLevel('warn')

app/tools/ConfigManager.js

@@ -5,6 +5,7 @@
   Merges the different config files and presents the configuration to the application
 */
 import defaultConfig from '../../config/default.config.js'
+import { deepMerge } from './Helper.js'
 
 async function getConfig () {
   let customConfig
@@ -15,27 +16,6 @@ async function getConfig () {
   return customConfig !== undefined ? deepMerge(defaultConfig, customConfig.default) : defaultConfig
 }
 
-export function deepMerge (...objects) {
-  const isObject = obj => obj && typeof obj === 'object'
-
-  return objects.reduce((prev, obj) => {
-    Object.keys(obj).forEach(key => {
-      const pVal = prev[key]
-      const oVal = obj[key]
-
-      if (Array.isArray(pVal) && Array.isArray(oVal)) {
-        prev[key] = pVal.concat(...oVal)
-      } else if (isObject(pVal) && isObject(oVal)) {
-        prev[key] = deepMerge(pVal, oVal)
-      } else {
-        prev[key] = oVal
-      }
-    })
-
-    return prev
-  }, {})
-}
-
 const config = await getConfig()
 
 export default config

app/tools/Helper.js

@@ -0,0 +1,28 @@
+'use strict'
+/*
+  Open Rowing Monitor, https://github.com/laberning/openrowingmonitor
+
+  Helper functions
+*/
+
+// deeply merges any number of objects into a new object
+export function deepMerge (...objects) {
+  const isObject = obj => obj && typeof obj === 'object'
+
+  return objects.reduce((prev, obj) => {
+    Object.keys(obj).forEach(key => {
+      const pVal = prev[key]
+      const oVal = obj[key]
+
+      if (Array.isArray(pVal) && Array.isArray(oVal)) {
+        prev[key] = pVal.concat(...oVal)
+      } else if (isObject(pVal) && isObject(oVal)) {
+        prev[key] = deepMerge(pVal, oVal)
+      } else {
+        prev[key] = oVal
+      }
+    })
+
+    return prev
+  }, {})
+}