I am creating a project in go. Since there is already a lot of things at the root of the repository of the project (doc, README.md...), I want all the source code to go in a folder src, and all the test code in a folder named test :
\go
\src
\github.com
\user
\my_project
\src
main.go
some_func.go
\test
test_main.go
test_some_func.go
\doc
README.md
But I have two issues :
I want all the source code to go in a folder src, and all the test code in a folder named test :
Go has a way that it organizes source code. Do not fight this. It is how the system works. Organize your code the way Go wants you to. Do not try to force Go to work the way you have learned working in some other language. Every language has its own ways of doing things. None of them are "correct." Like Java, Go has very specific ideas of what you're supposed to do. Do it that way. (This isn't an argument about whether Go is "right" or Go is "wrong." Go is Go, and it does things in the Go way.)
In particular, you should not create another "src" directory. There is already a "src" directory at the top of the "go" tree. If you create another, redundant, "src" directory, then the package name for your project is "github.com/user/my_project/src" which is likely not what you want.
To make the executable be named what you want, put it in a directory named what you want (probably "my_project"). Put test files with the files they test. This is how go works.
So your tree should look like:
\go
\src
\github.com
\user
\my_project
main.go
some_func.go
main_test.go
some_func_test.go
\doc
README.md
Attempts to do something other than this is going to blow up over and over again, and questions of "how do I make the build system do this other thing" will continually return "put your code in the way the build system expects."
For details on what Go expects, and how you should organize your code, see GOPATH environment variable in the Command Go documentation. Once you've built your system this way for a while, you will start to see where you can deviate from it (like creating other directories for test utilities, but not test cases). Don't start deviating until you've tried it the standard Go way.