1.8.9 Tesfor specific player at a specific xyz

Question

I'm trying to make this command work:

/testfor mastermc123 [x=506,y=4,z=-879,r=1] 

But I get this error:

Data tag parsing failed: Ivalid tag encountered expected { as first char

So, I tried:

/testfor mastermc123 {x=506,y=4,z=-879,r=1}

But I get this error:

Data tag parsing failed: unable too locate name/value separator for string x=506,y=4,z=-879,r=1

What is wrong here?

Answer 1

Selector arguments can only be used with a selector (@p, @a, @r, or @e). There must also be no space between the selector and the selector arguments:

/testfor @a[x=506,y=4,z=-879,r=1]

If you want to include a name, you can use the name= selector argument:

/testfor @a[x=506,y=4,z=-879,r=1,name=mastermc123]