)

type Man struct {
	ID     int
	Age    int
	Name   string
	Detail string
}

// Panic-safe BeforeUpdate hook that checks for Changed("age")
func (m *Man) BeforeUpdate(tx *gorm.DB) (err error) {
	if !tx.Statement.Changed("age") {
		return nil
	}
	return nil
}

func TestSubModel(t *testing.T) {
	man := Man{Age: 18, Name: "random-name"}
	if err := DB.Create(&man).Error; err != nil {

	return clause.Expr{SQL: "DEFAULT"}
}

func (DummyDialector) Migrator(*gorm.DB) gorm.Migrator {
	return nil
}

func (DummyDialector) BindVarTo(writer clause.Writer, stmt *gorm.Statement, v interface{}) {
	writer.WriteByte('?')
}

func (DummyDialector) QuoteTo(writer clause.Writer, str string) {
	var (
		underQuoted, selfQuoted bool
		continuousBacktick      int8
		shiftDelimiter          int8

# Probando WebSockets { #testing-websockets }

Puedes usar el mismo `TestClient` para probar WebSockets.

Para esto, usas el `TestClient` en un statement `with`, conectándote al WebSocket:

{* ../../docs_src/app_testing/tutorial002_py39.py hl[27:31] *}

/// note | Nota

	}}

	for idx, result := range results {
		t.Run(fmt.Sprintf("case #%v", idx), func(t *testing.T) {
			user, _ := schema.Parse(&tests.User{}, &sync.Map{}, db.NamingStrategy)
			stmt := &gorm.Statement{DB: db, Table: user.Table, Schema: user, Clauses: map[string]clause.Clause{}}
			clause.Expr{SQL: result.SQL, Vars: result.Vars}.Build(stmt)
			if stmt.SQL.String() != result.Result {

    /** {@literal true} if the iterator has more elements. */
    protected boolean hasNext = true;

    /**
     * Returns an {@link Iterable} that wraps a {@link SingleValueIterator} for use in a for-each statement.
     *
     * @param <E> the element type
     * @param value the single value returned by the iterator
     * @return an {@link Iterable} wrapping a {@link SingleValueIterator}
     */

# Testing Events: lifespan and startup - shutdown { #testing-events-lifespan-and-startup-shutdown }

When you need `lifespan` to run in your tests, you can use the `TestClient` with a `with` statement:

{* ../../docs_src/app_testing/tutorial004_py39.py hl[9:15,18,27:28,30:32,41:43] *}


You can read more details about the ["Running lifespan in tests in the official Starlette documentation site."](https://www.starlette.dev/lifespan/#running-lifespan-in-tests)

    protected final T[] items;

    /** The index of the currently referenced element */
    protected int index = 0;

    /**
     * Returns an {@link Iterable} that wraps the array for use in a for-each statement.
     *
     * @param <T> the type of elements
     * @param items the array of elements to iterate (must not be {@literal null})
     * @return an {@link Iterable} wrapping the array
     */

   * sneaky checked exception.
   *
   * @return never; this method declares a return type of {@link Error} only so that callers can
   *     write {@code throw sneakyThrow(t);} to convince the compiler that the statement will always
   *     throw.
   */
  @CanIgnoreReturnValue
  static Error sneakyThrow(Throwable t) {
    throw new SneakyThrows<Error>().throwIt(t);
  }

		// enable prepare statement
		tx3 := DB.Session(&gorm.Session{PrepareStmt: true})
		if err := tx3.Transaction(func(tx4 *gorm.DB) error {
			// nested transaction
			return tx4.Transaction(func(tx5 *gorm.DB) error {
				return tx5.First(&User{}, "name = ?", "transaction-2").Error
			})
		}); err != nil {
			t.Fatalf("prepare statement and nested transaction coexist: %v", err)
		}
	})
}

			sql: "INNER JOIN `user` USING (`id`)",
		},
	}
	for _, result := range results {
		t.Run(result.name, func(t *testing.T) {
			user, _ := schema.Parse(&tests.User{}, &sync.Map{}, db.NamingStrategy)
			stmt := &gorm.Statement{DB: db, Table: user.Table, Schema: user, Clauses: map[string]clause.Clause{}}
			result.join.Build(stmt)
			if result.sql != stmt.SQL.String() {
				t.Errorf("want: %s, got: %s", result.sql, stmt.SQL.String())
			}
		})