unit testing - How to test the main package functions in golang? -

i want test few functions included in main package, tests don't appear able access functions.

my sample main.go file looks like:

package main  import (     "log" )  func main() {     log.printf(foo()) }  func foo() string {     return "foo" } 

and main_test.go file looks like:

package main  import (     "testing" )  func foo(t testing.t) {     t.error(foo()) } 

when run go test main_test.go get

# command-line-arguments .\main_test.go:8: undefined: foo fail    command-line-arguments [build failed] 

as understand, if moved test file elsewhere , tried importing main.go file, couldn't import it, since it's package main.

what correct way of structuring such tests? should remove main package asides simple main function run , test functions in own package, or there way me call functions main file during testing?

when specify files on command line, have specify of them

here's run:

$ ls main.go     main_test.go $ go test *.go ok      command-line-arguments  0.003s 

note, in version, ran both main.go , main_test.go on command line

also, _test file not quite right, need test function called testxxx , take pointer testing.t

here's modified verison:

package main  import (     "testing" )  func testfoo(t *testing.t) {     t.error(foo()) } 

and modified output:

$ go test *.go --- fail: testfoo (0.00s)     main_test.go:8: foo fail fail    command-line-arguments  0.003s