为什么不引发“ go test -run testThatDoesNotExist”错误？

I just stumbled over a situation that made me curious. I spent half an hour to figure out why go test -run testWrittenWithSmallT is not executing my test. Except that I spelled it with a small t instead of T I noticed that go test passes if the given test method does not exist.

Little background: Initially I was wondering why my tests are not printing fmt.Println to stdout, or at least I thought that was the error. Only after a while I found out that the test is not executed at all.

So I am wondering, is there any reason why that should pass silently?

Examples go file:

package helloworld

import(
  "fmt"
  "testing"
)

func testWithSmallT(t *testing.T) {
    fmt.Println("test with small t executed")
}

func TestWithCapitalT(t *testing.T) {
    fmt.Println("test with capital T executed")
}

Test results:

$go test -run testWithSmallT
PASS
ok      starsheriff.net/helloworld  0.004s

$go test -run TestWithCapitalT
test with capital T executed
PASS
ok      starsheriff.net/helloworld  0.003s

$go test -run TestDoesNotExist
PASS
ok      starsheriff.net/helloworld  0.004s