How to test only one benchmark function?

In my Go package there are several benchmark files like map1_benchmark_test.go and map2_benchmark_test.go. In every *_benchmark_test.go file, there is more than one benchmark function like func BenchmarkMapTravel(b *testing.B) and func BenchmarkMapGet(b *testing.B).

Question is, how can I test just one benchmark function?

I attempted to read some manuals, and got nothing about benchmark by running go help test.

> Description of testing flags
>
> -test.bench pattern
> Run benchmarks matching the regular expression.
> By default, no benchmarks run.
>
> -test.run pattern
> Run only those tests and examples matching the regular
> expression.
> For convenience, each of these -test.X flags of the test binary is
> also available as the flag -X in 'go test' itself.

For help,

$ go help testflag

For example,

go test -test.bench MapTravel
go test -test.bench MapGet

or

go test -bench MapTravel
go test -bench MapGet

To bypass test functions, include a -test.run pattern that filters out every single test. For example,

go test -test.bench MapTravel -test.run=thisexpressionwontmatchanytest

or

go test -bench MapTravel -run=^$

There is no flag you can provide, that will run only benchmarks (or only one benchmark). The only flags related to these are:

> -bench regexp
> Run benchmarks matching the regular expression.
> By default, no benchmarks run. To run all benchmarks,
> use '-bench .' or '-bench=.'.
>
> -run regexp
> Run only those tests and examples matching the regular
> expression.

So if you want only to run one benchmark, you can do this:

go test -bench=nameOfYourBenchmark -run=^a

This will cause to run only tests that starts with a. And because each test should be named Test<something>, there will be no tests to run.

To run only benchmarks:

go test -bench=. -run=^a

Test only TestFuncOne

$>> go test -run TestFuncOne

> stuff_to_test.go

TestFuncOne() {
}

TestFuncTwo() {
}