path=example.com/m version=v1.0.0 wantErr=found go.mod file not in module root directory -- example.com/m@v1.0.0/a.go -- package a -- example.com/m@v1.0.0/b/GO.MOD -- MODULE EXAMPLE.COM/M/B -- example.com/m@v1.0.0/b/b.go -- package b