When I start the Minecraft program it brings up the launcher. When I hit the play button it shows that it is loading files. When that is done instead of loading the game it goes back to the launcher and lists the following information under the game output tab:

[22:07:40] [Client thread/INFO]: Setting user: FionnPietsch
[22:07:40] [Client thread/INFO]: (Session ID is token:48f9b7c1b6304230b877cbf05ef91c73:571300eb35834617a0609ea577d03208)
Exception in thread "Client thread" com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_ARRAY but was STRING at line 1 column 1
at com.google.gson.Gson.fromJson(Gson.java:815)
at com.google.gson.Gson.fromJson(Gson.java:768)
at lu.b(SourceFile:151)
at lu.<init>(SourceFile:43)
at net.minecraft.server.MinecraftServer.<init>(SourceFile:155)
at bpp.<init>(SourceFile:41)
at avf.<init>(SourceFile:293)
at net.minecraft.client.main.Main.main(SourceFile:124)
Caused by: java.lang.IllegalStateException: Expected BEGIN_ARRAY but was STRING at line 1 column 1
at com.google.gson.stream.JsonReader.beginArray(JsonReader.java:338)
at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:79)
at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:60)
at com.google.gson.Gson.fromJson(Gson.java:803)
... 7 more
Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and will likely be removed in a future release

What I expected to happen was...:
I expect the game to launch and play

What actually happened was...:
I am unable to play the game.

Steps to Reproduce:
It happens every time I try to launch the game today