adds validate command

create.go

@@ -65,7 +65,7 @@ func Create(
 
 	version := now.Format(timestampFormat)
 	if opt.Sequential {
-		sources, err := Collect(osFS{}, dir, true, nil)
+		sources, err := collect(osFS{}, dir, true, nil)
 		if err != nil {
 			return "", err
 		}

fix.go

@@ -17,7 +17,7 @@ func Fix(dir string) ([]FixResult, error) {
 	if dir == "" {
 		return nil, fmt.Errorf("dir is required")
 	}
-	sources, err := Collect(osFS{}, dir, true, nil)
+	sources, err := collect(osFS{}, dir, true, nil)
 	if err != nil {
 		return nil, err
 	}

internal/cli/cmd_validate.go

@@ -11,6 +11,7 @@ import (
 	"text/tabwriter"
 
 	"github.com/peterbourgon/ff/v3/ffcli"
+	"github.com/pressly/goose/v4"
 	"github.com/pressly/goose/v4/internal/migrationstats"
 	"github.com/pressly/goose/v4/internal/migrationstats/migrationstatsos"
 )
@@ -48,9 +49,17 @@ func (c *validateCmd) Exec(ctx context.Context, args []string) error {
 	if dir == "" {
 		return fmt.Errorf("goose validate requires a migrations directory: %w", errNoDir)
 	}
-
-	filenames := []string{} // TODO(mf): fix me
-
+	sources, err := goose.Collect(dir, c.excludeFilenames)
+	if err != nil {
+		return err
+	}
+	if len(sources) == 0 {
+		return fmt.Errorf("goose: no migration sources found in %q", dir)
+	}
+	filenames := make([]string, 0, len(sources))
+	for _, src := range sources {
+		filenames = append(filenames, src.Fullpath)
+	}
 	fileWalker := migrationstatsos.NewFileWalker(filenames...)
 	stats, err := migrationstats.GatherStats(fileWalker, false)
 	if err != nil {

provider.go

@@ -48,7 +48,7 @@ func NewProvider(dbDialect Dialect, db *sql.DB, opt Options) (*Provider, error)
 	if opt.LockMode != LockModeNone && !store.CanLock() {
 		return nil, fmt.Errorf("locking is not supported for %s", dbDialect)
 	}
-	sources, err := Collect(opt.Filesystem, opt.Dir, true, opt.ExcludeFilenames)
+	sources, err := collect(opt.Filesystem, opt.Dir, true, opt.ExcludeFilenames)
 	if err != nil {
 		return nil, err
 	}

source.go

@@ -29,6 +29,7 @@ func (t SourceType) String() string {
 	}
 }
 
+// Source represents a single migration source file on disk.
 type Source struct {
 	// Full path to the migration file.
 	//
@@ -40,7 +41,12 @@ type Source struct {
 	Type SourceType
 }
 
-func Collect(fsys fs.FS, dir string, strict bool, excludes []string) ([]*Source, error) {
+// Collect returns a slice of Sources found in the given directory.
+func Collect(dir string, excludes []string) ([]*Source, error) {
+	return collect(osFS{}, dir, false, excludes)
+}
+
+func collect(fsys fs.FS, dir string, strict bool, excludes []string) ([]*Source, error) {
 	if _, err := fs.Stat(fsys, dir); errors.Is(err, fs.ErrNotExist) {
 		return nil, fmt.Errorf("directory does not exist: %s", dir)
 	}