ldrrandgen: recursively check types for refcursor

This adjusts the ldr table generator to avoid generating random types
that contain a refcursor.

Release note: none
Fixes: 157026

Author: jeffswenson

pkg/crosscluster/ldrrandgen/logical.go

@@ -15,6 +15,30 @@ import (
 	"github.com/cockroachdb/cockroach/pkg/sql/types"
 )
 
+func isSupportedType(t *types.T) bool {
+	switch t.Family() {
+	case types.RefCursorFamily:
+		// We don't support RefCursor columns in LDR tables because they do not
+		// support equality.
+		return false
+	case types.ArrayFamily:
+		// We don't allow Arrays of bits because rand.LoadTable doesn't correctly identify their bit width.
+		if t.ArrayContents().Family() == types.BitFamily {
+			return false
+		}
+		return isSupportedType(t.ArrayContents())
+	case types.TupleFamily:
+		for _, elemType := range t.TupleContents() {
+			if !isSupportedType(elemType) {
+				return false
+			}
+		}
+		return true
+	default:
+		return true
+	}
+}
+
 func GenerateLDRTable(
 	ctx context.Context, rng *rand.Rand, tableName string, supportKVWriter bool,
 ) *tree.CreateTable {
@@ -31,21 +55,7 @@ func GenerateLDRTable(
 		randgen.WithPrimaryIndexRequired(),
 		randgen.WithSkipColumnFamilyMutations(),
 		randgen.WithColumnFilter(func(columnDef *tree.ColumnTableDef) bool {
-			// We don't allow Arrays of bits because rand.LoadTable doesn't correctly identify their bit width.
-			if columnDef.Type.(*types.T).Family() == types.ArrayFamily && columnDef.Type.(*types.T).ArrayContents().Family() == types.BitFamily {
-				return false
-			}
-			// We don't support RefCursor columns in LDR tables because they do not
-			// support equality.
-			if columnDef.Type.(*types.T).Family() == types.RefCursorFamily {
-				return false
-			}
-			// We don't allow the special '"char"' column because pgwire truncates the value to 1 byte.
-			// TODO(jeffswenson): remove this once #149427 is fixed.
-			if columnDef.Type.(*types.T).Family() == types.StringFamily && columnDef.Type.(*types.T).Width() == 1 {
-				return false
-			}
-			return true
+			return isSupportedType(columnDef.Type.(*types.T))
 		}),
 		randgen.WithPrimaryIndexFilter(func(indexDef *tree.IndexTableDef, columnDefs []*tree.ColumnTableDef) bool {
 			for _, col := range indexDef.Columns {