From fc6dd134821b20304eaa14bdcce36518b9f699cd Mon Sep 17 00:00:00 2001
From: Jeff Linse <jeff@jefflinse.com>
Date: Fri, 9 May 2025 19:18:57 -0700
Subject: [PATCH] Add support for scanning Postgres tuples

---
 typeid/typeid-go/sql.go      | 34 ++++++++++++++++++++++++++++++----
 typeid/typeid-go/sql_test.go | 12 +++++++++---
 2 files changed, 39 insertions(+), 7 deletions(-)

diff --git a/typeid/typeid-go/sql.go b/typeid/typeid-go/sql.go
index be901538..07c47fff 100644
--- a/typeid/typeid-go/sql.go
+++ b/typeid/typeid-go/sql.go
@@ -3,8 +3,11 @@ package typeid
 import (
 	"database/sql/driver"
 	"fmt"
+	"strings"
 )
 
+const minTupleStringLength = 40 // (x,00000000-0000-0000-0000-000000000000)
+
 // Scan implements the sql.Scanner interface so the TypeIDs can be read from
 // databases transparently. Currently database types that map to string are
 // supported.
@@ -17,10 +20,33 @@ func (tid *TypeID[P]) Scan(src any) error {
 			return nil
 		}
 		return tid.UnmarshalText([]byte(obj))
-	// TODO: add support for []byte
-	// we don't just want to store the full string as a byte array. Instead
-	// we should encode using the UUID bytes. We could add support for
-	// Binary Marshalling and Unmarshalling at the same time.
+	case []byte:
+		if len(obj) == 0 {
+			return nil
+		}
+
+		// typeid-sql can store TypeIDs as tuples of the form (prefix,uuid).
+		if len(obj) < minTupleStringLength || obj[0] != '(' || obj[len(obj)-1] != ')' {
+			// TODO: add support for []byte
+			// we don't just want to store the full string as a byte array. Instead
+			// we should encode using the UUID bytes. We could add support for
+			// Binary Marshalling and Unmarshalling at the same time.
+			return fmt.Errorf("unsupported format for scan type %T", obj)
+		}
+
+		obj = obj[1 : len(obj)-1]
+		parts := strings.Split(string(obj), ",")
+		if len(parts) != 2 {
+			return fmt.Errorf("invalid TypeID format: %s", obj)
+		}
+
+		parsedID, err := fromUUID[TypeID[P]](parts[0], parts[1])
+		if err != nil {
+			return fmt.Errorf("invalid UUID: %s: %w", parts[1], err)
+		}
+
+		*tid = parsedID
+		return nil
 	default:
 		return fmt.Errorf("unsupported scan type %T", obj)
 	}
diff --git a/typeid/typeid-go/sql_test.go b/typeid/typeid-go/sql_test.go
index 221cc4ba..185abc22 100644
--- a/typeid/typeid-go/sql_test.go
+++ b/typeid/typeid-go/sql_test.go
@@ -8,18 +8,23 @@ import (
 )
 
 func TestScan(t *testing.T) {
+	t.Parallel()
+
 	testdata := []struct {
 		name     string
 		input    any
 		expected typeid.AnyID
 	}{
-		{"valid", "prefix_00041061050r3gg28a1c60t3gf", typeid.Must(typeid.FromString("prefix_00041061050r3gg28a1c60t3gf"))},
+		{"valid_text", "prefix_01jtvs4hppfp8azhhy9x703dc1", typeid.Must(typeid.FromString("prefix_01jtvs4hppfp8azhhy9x703dc1"))},
+		{"valid_tuple", []byte("(prefix,0196b792-46d6-7d90-afc6-3e4f4e01b581)"), typeid.Must(typeid.FromString("prefix_01jtvs4hppfp8azhhy9x703dc1"))},
 		{"nil", nil, typeid.AnyID{}},
 		{"empty string", "", typeid.AnyID{}},
 	}
 
 	for _, td := range testdata {
 		t.Run(td.name, func(t *testing.T) {
+			t.Parallel()
+
 			var scanned typeid.AnyID
 			err := scanned.Scan(td.input)
 			assert.NoError(t, err)
@@ -31,8 +36,9 @@ func TestScan(t *testing.T) {
 }
 
 func TestValuer(t *testing.T) {
-	expected := "prefix_00041061050r3gg28a1c60t3gf"
-	tid := typeid.Must(typeid.FromString("prefix_00041061050r3gg28a1c60t3gf"))
+	t.Parallel()
+	expected := "prefix_01jtvs4hppfp8azhhy9x703dc1"
+	tid := typeid.Must(typeid.FromString("prefix_01jtvs4hppfp8azhhy9x703dc1"))
 	actual, err := tid.Value()
 	assert.NoError(t, err)
 	assert.Equal(t, expected, actual)