NullPointerException in ShellImpl.testCmd

[hemisphire]

Looks like testCmd doesn't check for a non null result returned from fastCmd before using split()

FATAL EXCEPTION: main
Process: com.topjohnwu.magisk, PID: 23379
java.lang.ExceptionInInitializerError
at com.topjohnwu.magisk.database.SuDatabaseHelper.openDatabase(Unknown Source)
at com.topjohnwu.magisk.database.SuDatabaseHelper.(Unknown Source)
at com.topjohnwu.magisk.database.SuDatabaseHelper.getInstance(Unknown Source)
at com.topjohnwu.magisk.MagiskManager.onCreate(Unknown Source)
at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1036)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:6321)
at android.app.ActivityThread.access$1800(ActivityThread.java:222)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1861)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:158)
at android.app.ActivityThread.main(ActivityThread.java:7229)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String[] java.lang.String.split(java.lang.String)' on a null object reference
at com.topjohnwu.superuser.internal.ShellImpl.testCmd(Unknown Source)
at com.topjohnwu.superuser.io.SuFile.testShell(Unknown Source)
at com.topjohnwu.superuser.io.SuFile.(Unknown Source)
at com.topjohnwu.magisk.utils.Const.(Unknown Source)
at com.topjohnwu.magisk.database.SuDatabaseHelper.openDatabase(Unknown Source) 
at com.topjohnwu.magisk.database.SuDatabaseHelper.(Unknown Source) 
at com.topjohnwu.magisk.database.SuDatabaseHelper.getInstance(Unknown Source) 
at com.topjohnwu.magisk.MagiskManager.onCreate(Unknown Source) 
at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:1036) 
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:6321) 
at android.app.ActivityThread.access$1800(ActivityThread.java:222) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1861) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:158) 
at android.app.ActivityThread.main(ActivityThread.java:7229) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)