Temporary symbol leaks into public context?

Question

This phenomenon has confused me a long time. Consider the following package example,

BeginPackage["temp`"];
test;
test2;
Begin["Private"];
f[x_]:=
    test_:>{x,test};
f2[x_]:=
    test2_:>{test2};
End[];
EndPackage[];

where test2 is for comparison.

Then in notebook evaluate the following test code with a fresh kernel,

<<temp`
Names["temp`*"]
??test$
??temp`test2$

It's weird that the temporary symbol test$ leaks into the public context temp` . Notice that:

• the leaked temporary symbol must have the same name as the public one;

• the local symbol x in the definition of f is necessary to repeat this behaviour.

Is this a bug?