When placing a item frame in your 14w18a world, the game crashes. I got a crash error, it is showed below.

It could also be possible that your world could be corrupted, making the words "Snapshots can corrupt your world, please backup and/or run them in a different folder from your main worlds." serious.

How to reproduce:
1.Get a item frame
2.Place the item frame
3.CRASH!

Crash Report:
---- Minecraft Crash Report ----
// I let you down. Sorry

Time: 4/30/14 8:40 PM
Description: Rendering entity in world

java.lang.NullPointerException: Rendering entity in world
at cce.a(SourceFile:79)
at cce.a(SourceFile:53)
at cce.a(SourceFile:24)
at cbt.a(SourceFile:219)
at cbt.a(SourceFile:199)
at cbt.a(SourceFile:176)
at bxs.a(SourceFile:495)
at bxl.a(SourceFile:1146)
at bxl.b(SourceFile:935)
at bjf.ai(SourceFile:828)
at bjf.f(SourceFile:755)
at net.minecraft.client.main.Main.main(SourceFile:121)

A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

– Head –
Stacktrace:
at cce.a(SourceFile:79)
at cce.a(SourceFile:53)
at cce.a(SourceFile:24)

– Entity being rendered –
Details:
Entity Type: ItemFrame (uh)
Entity ID: 4
Entity Name: entity.ItemFrame.name
Entity's Exact location: -871.50, 62.50, 984.97
Entity's Block location: -872.00,62.00,984.00 - World: (-872,62,984), Chunk: (at 8,3,8 in -55,61; contains blocks -880,0,976 to -865,255,991), Region: (-2,1; contains chunks -64,32 to -33,63, blocks -1024,0,512 to -513,255,1023)
Entity's Momentum: 0.00, 0.00, 0.00
Entity's Rider: ~_ERROR~ NullPointerException: null
Entity's Vehicle: ~_ERROR~ NullPointerException: null

– Renderer details –
Details:
Assigned renderer: cce@5d8f794f
Location: -0.09,0.50,2.04 - World: (-1,0,2), Chunk: (at 15,0,2 in -1,0; contains blocks -16,0,0 to -1,255,15), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Rotation: 180.0
Delta: 0.056967735
Stacktrace:
at cbt.a(SourceFile:219)
at cbt.a(SourceFile:199)
at cbt.a(SourceFile:176)
at bxs.a(SourceFile:495)
at bxl.a(SourceFile:1146)

– Affected level –
Details:
Level name: MpServer
All players: 1 total; [bxb['OceanTotato'/32, l='MpServer', x=-871.41, y=62.00, z=982.92]]
Chunk stats: MultiplayerChunkCache: 170, 170
Level seed: 0
Level generator: ID 01 - flat, ver 0. Features enabled: false
Level generator options:
Level spawn location: -863.00,4.00,964.00 - World: (-863,4,964), Chunk: (at 1,0,4 in -54,60; contains blocks -864,0,960 to -849,255,975), Region: (-2,1; contains chunks -64,32 to -33,63, blocks -1024,0,512 to -513,255,1023)
Level time: 50776 game time, 48376 day time
Level dimension: 0
Level storage version: 0x00000 - Unknown?
Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: false
Forced entities: 12 total; [yj['Pig'/0, l='MpServer', x=-887.22, y=62.00, z=1022.88], yj['Pig'/1, l='MpServer', x=-883.50, y=62.00, z=1055.50], yj['Pig'/2, l='MpServer', x=-882.18, y=62.00, z=1054.33], yb['Cow'/3, l='MpServer', x=-882.50, y=62.00, z=1051.50], uh['entity.ItemFrame.name'/4, l='MpServer', x=-871.50, y=62.50, z=984.97], bxb['OceanTotato'/32, l='MpServer', x=-871.41, y=62.00, z=982.92], up['Painting'/5, l='MpServer', x=-872.00, y=64.00, z=990.97], yj['Pig'/6, l='MpServer', x=-876.19, y=62.00, z=1025.44], yj['Pig'/7, l='MpServer', x=-875.19, y=62.00, z=1059.75], yj['Pig'/11, l='MpServer', x=-846.00, y=62.00, z=1021.94], yj['Pig'/14, l='MpServer', x=-823.16, y=62.00, z=999.38], up['Painting'/5, l='MpServer', x=-872.00, y=64.00, z=990.97]]
Retry entities: 0 total; []
Server brand: vanilla
Server type: Integrated singleplayer server
Stacktrace:
at buw.a(SourceFile:308)
at bjf.b(SourceFile:2069)
at bjf.f(SourceFile:764)
at net.minecraft.client.main.Main.main(SourceFile:121)

– System Details –
Details:
Minecraft Version: 14w18a
Operating System: Mac OS X (x86_64) version 10.9.2
Java Version: 1.6.0_65, Apple Inc.
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
Memory: 74237056 bytes (70 MB) / 195485696 bytes (186 MB) up to 1065025536 bytes (1015 MB)
JVM Flags: 1 total; -Xmx1G
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
Launched Version: 14w18a
LWJGL: 2.9.1
OpenGL: Intel HD Graphics 3000 OpenGL Engine GL version 2.1 INTEL-8.24.11, Intel Inc.
GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because ARB_framebuffer_object is supported and separate blending is supported.
Anisotropic filtering is supported and maximum anisotropy is 16.
Shaders are available because OpenGL 2.1 is supported.

Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: []
Current Language: English (US)
Profiler Position: N/A (disabled)
Anisotropic Filtering: Off (1)