NamedParameterUtils has broken square brackets handling

[artembilan]

This is a simple unit test which passes with the 5.3.x but fails with the current 6.0 milestones:

	@Test
	void namedParamMapReference() {
		String insert = "insert into foos (id) values (:headers[id])";
		class Foo {

			final Map<String, Object> headers = new HashMap<>();

			public Foo() {
				this.headers.put("id", UUID.randomUUID());
			}

			public Map<String, Object> getHeaders() {
				return this.headers;
			}

		}

		Foo foo = new Foo();

		Object[] params =
				NamedParameterUtils.buildValueArray(NamedParameterUtils.parseSqlStatement(insert),
						new BeanPropertySqlParameterSource(foo), null);

		assertThat(params[0]).isEqualTo(foo.getHeaders().get("id"));
	}

The point is that we may have a reference for the value from nested Map property.

The typical use case is messaging, for example with Spring Integration, where a Message<?> in the request is used as a source for parameter values.

We even advertise this in the docs: https://docs.spring.io/spring-integration/docs/current/reference/html/jdbc.html#jdbc-outbound-channel-adapter.

I suspect that the cause for breaking change is this fix: 64b6bee. Or the previous one: 86eda27.

Thanks

[quaff]

parameterName is changed from headers[id] to headers after commit 64b6bee

[rstoyanchev]

Maybe consider #17773 as well for potential improvement to the parsing algorithm.

[jhoeller]

With some custom treatment, we can restore the original intent of #27716 as well as preserve square brackets for index/key expressions. Finally making it into RC2...