e2e: add some comments

android/build.gradle

@@ -3,10 +3,12 @@
 buildscript {
     ext {
         buildToolsVersion = "28.0.3"
+        // detox requires at least version 18
         minSdkVersion = 18
         compileSdkVersion = 28
         targetSdkVersion = 28
         supportLibVersion = "28.0.0"
+        // detox instrumentation app uses kotlin
         kotlinVersion = "1.3.0"
     }
     repositories {
@@ -15,6 +17,7 @@ buildscript {
     }
     dependencies {
         classpath 'com.android.tools.build:gradle:3.3.1'
+        // detox instrumentation app uses kotlin
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlinVersion"
 
         // NOTE: Do not place your application dependencies here; they belong

e2e/init.js

@@ -10,16 +10,21 @@ const adb = new ADB()
 jest.setTimeout(120000)
 jasmine.getEnv().addReporter(adapter)
 
-// This takes care of generating status logs on a per-spec basis. By default, jest only reports at file-level.
-// This is strictly optional.
+// This takes care of generating status logs on a per-spec basis. By default,
+// jest only reports at file-level.  This is strictly optional.
 jasmine.getEnv().addReporter(specReporter)
 
 beforeAll(async () => {
   const configs = detoxConfig.configurations
+
+  // TODO figure out iOS configs
   const newConfigs = detoxConfig.configurations = {
     'ios.sim.debug': configs['ios.sim.debug']
   }
 
+  // detox device configurations are generated dynamically here after querying
+  // ADB for android devices and emulator, instead of hardcoding in package.json
+
   try {
     const devices = await adb.devices()
     devices.forEach(device => {

e2e/utils.ts

@@ -1,6 +1,10 @@
 import { expect } from 'detox'
 
-// courtsey of https://github.com/wix/detox/issues/445#issuecomment-514801808
+/**
+ * @async
+ * @desc Given a testID of a <Text> element, returns the visible text in it
+ *       courtsey of https://github.com/wix/detox/issues/445#issuecomment-514801808
+ */
 export const readVisibleText = async (testID: string) => {
   try {
     await expect(element(by.id(testID))).toHaveText('_you_cant_possible_have_this_text_')