Goa is awesome, but we have seen an issue which occures when doing:

	dsl.Files("/mysuperduperapi.json", "a/b/c/openapi3.json")

The code does produces ([code])(https://github.com/goadesign/examples/blob/master/basic/gen/http/calc/server/server.go#L56)

	fileSystemPkgGenHTTPOpenapi3JSON = appendPrefix(fileSystemPkgGenHTTPOpenapi3JSON, "/a/b/c")

but if the a/b/c/ is dropped, e.g. dsl.Files("/mysuperduperapi.json", "openapi3.json")

Goa does not generate the appendPrefix which does not result in selecting the openapi3.json but trying to access mysuperduperapi.json (instead of openapi.json)
So I think appendPrefix should always be generate even if its with "." to select the openapi3.json.

P.S. Maybe this is also intended behavior, but its kind of odd, because only

• dsl.Files("/openapi3.json", "openapi3.json") works
• dsl.Files("/openapi.json", "openapi3.json") does not work

This is triggered by this line basically