fix: 🐛 Config array merging (#391)

* fix: 🐛 Overwrite default array options

* 🚨 tslint auto-fix

.ci.percy.yml

@@ -1,5 +1,6 @@
 version: 1
 snapshot:
+  widths: [375, 1200]
   percy-css: |
     .percy-only-css-global {
       height: 300px;

src/services/image-snapshot-service.ts

@@ -150,6 +150,6 @@ export default class ImageSnapshotService extends PercyClientService {
     await this.buildService.finalize()
 
     // if an error occurred, exit with non-zero
-    if (error) process.exit(1)
+    if (error) { process.exit(1) }
   }
 }

src/utils/configuration.ts

@@ -81,5 +81,9 @@ export default function config({ config, ...flags }: any, args: any = {}) {
     logger.debug(`Using config: ${inspect(overrides, { depth: null })}`)
   }
 
-  return merge.all([DEFAULT_CONFIGURATION, overrides].filter(Boolean)) as Configuration
+  return merge.all(
+    [DEFAULT_CONFIGURATION, overrides].filter(Boolean),
+    // overwrite default arrays, do not merge
+    { arrayMerge: (_, arr) => arr },
+  ) as Configuration
 }