I am attempting to understand how to structure a go project into sub modules stored in separate source code repositories (on host example.com), however when I do, I am not sure how to run the tests that are within a module. What am doing wrong in the following example, any help is much appreciated!!
mkdir -p src/example.com/john/tool
echo "package tool" >> src/example.com/john/tool/book.go
echo "" >> src/example.com/john/tool/book.go
echo "type Book struct {" >> src/example.com/john/tool/book.go
echo " Title string" >> src/example.com/john/tool/book.go
echo "}" >> src/example.com/john/tool/book.go
echo "" >> src/example.com/john/tool/book.go
echo "package tool" >> src/example.com/john/tool/book_test.go
echo "" >> src/example.com/john/tool/book_test.go
echo "import (" >> src/example.com/john/tool/book_test.go
echo " \"tool\"" >> src/example.com/john/tool/book_test.go
echo " \"testing\"" >> src/example.com/john/tool/book_test.go
echo ")" >> src/example.com/john/tool/book_test.go
echo "" >> src/example.com/john/tool/book_test.go
echo "func TestBook(t *testing.T) { }" >> src/example.com/john/tool/book_test.go
echo "" >> src/example.com/john/tool/book_test.go
export GOPATH=`pwd`
go test example.com/john/tool
When I run this test, this is the error I am seeing:
# example.com/john/tool
src/example.com/john/tool/book_test.go:4:3: cannot find package "tool" in any of:
/usr/local/go/src/tool (from $GOROOT)
/Users/john/app/src/tool (from $GOPATH)
FAIL example.com/john/tool [setup failed]
Obviously book_test.go can't import the "tool" package, an you could probably put in the full path, but when I look in github, no one does that in their modules. So I don't understand what I am doing wrong.
Your line
import "tool"
is the offender. There is no package tool in the standard library and your package tool has an import path of example.com/john/tool.
Just drop that import. There is no need to import the current package (and it is impossible as this would be a (degenerated) import cycle).