[enhancement] LoadMigrations with a given path

[emicklei]

I am trying to use the package as a library.

For that, I created embedded FS and wanted to use LoadMigrations.

However, in github.com/jackc/tern/v2 v2.3.2 that function expects to find migrations in the current "." folder whereas my FS requires a path.

//go:embed services/content/db/migrations/*.sql
var content embed.FS

Would you consider adding another Load function that takes a path parameter?

[emicklei]

As a workaround? , I am using this FS implementation , LoadMigrations(NewSubFS(fs,path))

type SubFS struct {
	fs        embed.FS
	subfolder string
}

func NewSubFS(fs embed.FS, subfolder string) SubFS {
	return SubFS{
		fs:        fs,
		subfolder: subfolder,
	}
}

func (s SubFS) Open(name string) (fs.File, error) {
	f, err := s.fs.Open(filepath.Join(s.subfolder, name))
	if err != nil {
		return nil, err
	}
	return f, nil
}

func (s SubFS) ReadDir(name string) ([]fs.DirEntry, error) {
	entries, err := s.fs.ReadDir(filepath.Join(s.subfolder, name))
	if err != nil {
		return nil, err
	}
	return entries, nil
}

func (s SubFS) ReadFile(name string) ([]byte, error) {
	data, err := s.fs.ReadFile(filepath.Join(s.subfolder, name))
	if err != nil {
		return nil, err
	}
	return data, nil
}

[jackc]

That seems like a decent workaround.

[kernel-panic96]

+1 to the request.

Maybe a new function or change the existing one to recurse one level deep, if the only entry is a directory?

P.S: thank you for the workaround @emicklei

[jackc]

It appears the workaround is actually in the standard library: https://pkg.go.dev/io/fs#Sub