Remove Goose rollback statements

goose.go

@@ -0,0 +1,15 @@
+package dinosql
+
+import "strings"
+
+// Remove all lines after a `-- +goose Down` comment
+func RemoveGooseRollback(contents string) string {
+	lines := strings.Split(contents, "\n")
+	for i, line := range lines {
+		if strings.HasPrefix(strings.TrimSpace(line), "-- +goose Down") {
+			lines = lines[:i]
+			break
+		}
+	}
+	return strings.Join(lines, "\n")
+}

goose_test.go

@@ -0,0 +1,26 @@
+package dinosql
+
+import (
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+const inputMigration = `
+-- +goose Up
+ALTER TABLE archived_jobs ADD COLUMN expires_at TIMESTAMP WITH TIME ZONE;
+
+-- +goose Down
+ALTER TABLE archived_jobs DROP COLUMN expires_at;
+`
+
+const outputMigration = `
+-- +goose Up
+ALTER TABLE archived_jobs ADD COLUMN expires_at TIMESTAMP WITH TIME ZONE;
+`
+
+func TestRemoveGooseRollback(t *testing.T) {
+	if diff := cmp.Diff(outputMigration, RemoveGooseRollback(inputMigration)); diff != "" {
+		t.Errorf("migration mismatch:\n%s", diff)
+	}
+}

parser.go

@@ -57,7 +57,8 @@ func ParseSchmea(dir string) (*postgres.Schema, error) {
 		if err != nil {
 			return nil, err
 		}
-		tree, err := pg.Parse(string(blob))
+		contents := RemoveGooseRollback(string(blob))
+		tree, err := pg.Parse(contents)
 		if err != nil {
 			return nil, err
 		}