Question: Error, (in type/algext) too many levels of recursion

I made a typo below, I did not mean to put [...] around the solution. But why Maple throws an error on this only?

restart;
ode:=diff(y(x),x) = exp(x)*sin(x)+y(x)*cot(x);
my_sol:=[sin(x)*(exp(x)+_C1)];
odetest( y(x)=my_sol,ode) assuming x::real

          Error, (in type/algext) too many levels of recursion

But on other ODE's, it works

restart;
ode:=diff(y(x),x) = y(x);
my_sol:=[_C1*exp(x)];
odetest( y(x)=my_sol,ode) assuming x::real

                [0]

I'll correct my type and remove the []. But the question is, should Maple have thrown an error? And why only on this one? Would this be considered a bug?

Removing the [] from the first example above, the error is gone and 0 is returned.

Maple 2019.1, Physics V 395 on windows 10