Update: Drop dependency to deepmerge

Author: thomasthiebaud

package-lock.json

@@ -28,7 +28,6 @@
   "devDependencies": {
     "@semantic-release/changelog": "2.1.1",
     "@semantic-release/git": "6.0.1",
-    "@types/deepmerge": "2.1.0",
     "@types/dompurify": "0.0.31",
     "@types/enzyme": "3.1.11",
     "@types/jest": "23.1.4",
@@ -49,7 +48,6 @@
     "typescript": "2.9.2"
   },
   "dependencies": {
-    "deepmerge": "2.1.1",
     "dompurify": "1.0.5"
   },
   "peerDependencies": {

package.json

@@ -1,4 +1,24 @@
-import * as deepmerge from 'deepmerge'
+function isObject(item: any) {
+  return (item && typeof item === 'object' && !Array.isArray(item))
+}
+
+function deepMerge(target: any, source: any) {
+  const output = Object.assign({}, target)
+  if (isObject(target) && isObject(source)) {
+    Object.keys(source).forEach((key) => {
+      if (isObject(source[key])) {
+        if (!(key in target)) {
+          Object.assign(output, { [key]: source[key] })
+        } else {
+          output[key] = deepMerge(target[key], source[key])
+        }
+      } else {
+        Object.assign(output, { [key]: source[key] })
+      }
+    })
+  }
+  return output
+}
 
 export interface UserProfiles {
   html?: boolean
@@ -49,8 +69,8 @@ const defaultOptions: Options = {
 
 export function getOptions(options?: Partial<Options>): Options {
   if (options) {
-    return deepmerge.all<Options>([defaultOptions, options, mandatoryOptions])
+    return deepMerge(defaultOptions, deepMerge(options, mandatoryOptions))
   } else {
-    return deepmerge.all<Options>([defaultOptions, mandatoryOptions])
+    return deepMerge(defaultOptions, mandatoryOptions)
   }
 }