snapshot of https://github.com/golang-migrate/migrate.git (master, 2026-09-15; blobs > 131072B omitted)

database/multistmt/parse.go

@@ -0,0 +1,46 @@
+// Package multistmt provides methods for parsing multi-statement database migrations
+package multistmt
+
+import (
+	"bufio"
+	"bytes"
+	"io"
+)
+
+// StartBufSize is the default starting size of the buffer used to scan and parse multi-statement migrations
+var StartBufSize = 4096
+
+// Handler handles a single migration parsed from a multi-statement migration.
+// It's given the single migration to handle and returns whether or not further statements
+// from the multi-statement migration should be parsed and handled.
+type Handler func(migration []byte) bool
+
+func splitWithDelimiter(delimiter []byte) func(d []byte, atEOF bool) (int, []byte, error) {
+	return func(d []byte, atEOF bool) (int, []byte, error) {
+		// SplitFunc inspired by bufio.ScanLines() implementation
+		if atEOF {
+			if len(d) == 0 {
+				return 0, nil, nil
+			}
+			return len(d), d, nil
+		}
+		if i := bytes.Index(d, delimiter); i >= 0 {
+			return i + len(delimiter), d[:i+len(delimiter)], nil
+		}
+		return 0, nil, nil
+	}
+}
+
+// Parse parses the given multi-statement migration
+func Parse(reader io.Reader, delimiter []byte, maxMigrationSize int, h Handler) error {
+	scanner := bufio.NewScanner(reader)
+	scanner.Buffer(make([]byte, 0, StartBufSize), maxMigrationSize)
+	scanner.Split(splitWithDelimiter(delimiter))
+	for scanner.Scan() {
+		cont := h(scanner.Bytes())
+		if !cont {
+			break
+		}
+	}
+	return scanner.Err()
+}