Bug in data tags parsing in a "setblock" command but the same data tags works in a testfor command

I have a command-block with a setblock command that replace an other command block with a testfor command (to reset the signal). The command in the testfor works well but the command in the setblock give me the following error: "Data tag parsing failed" but I've checked and there is no error

Testfor command:
/testfor @a {SelectedItemSlot:1,Inventory:[{Slot:1b,id:"minecraft:paper",tag:{display:

{Name:"Fireball",Lore:["Hold this spell in your hand","to create a Fireball that youcan","shoot on your ennemies by clicking on it"]}

,ench:[

{id:0,lvl:0}

],HideFlags:1}}]}

Output: Found Julien008 (the command works)

Setblock command:
setblock ~-2 ~-1 ~ minecraft:command_block 0 replace {Command:"/testfor @a {SelectedItemSlot:1,Inventory:[{Slot:1b,id:"minecraft:paper",tag:{display:

{Name:"Fireball",Lore:["Hold this spell in your hand","to create a Fireball that youcan","shoot on your ennemies by clicking on it"]}

,ench:[

{id:0,lvl:0}

],HideFlags:1}}]}"}

Output: [20:13:28] Data tag parsing failed: Unexpected token 'm' at: minecraft:paper",tag:{display:

{Name:"Fireball",Lore:["Hold this spell in your hand","to create a Fireball that you can","shoot on your ennemies by clicking on it"]}

,ench:[

{id:0,lvl:0}

],HideFlags:1}}]}"

I think there is a problem with TileID integration