@Test
void append() {

    var builder = new StringBuilder();
    filter.append(builder, "{}", 1);
    assertThat(builder.toString()).isEqualTo("1");
    builder = new StringBuilder();
    filter.append(builder, "{}-text", 1);
    assertThat(builder.toString()).isEqualTo("1-text");
    builder = new StringBuilder();
    filter.append(builder, "message, null={}, object={}, map={}, object[]={}, int[]={}, boolean[]={}, char[]={}", null,
            "string",
            Map.of("key", "value"),
            new Object[]{1, "string", null},
            new int[]{1, 2, 3},
            new boolean[]{true},
            new char[]{'1', '2'});
    assertThat(builder.toString()).contains("message,")
                                  .contains("null=null,")
                                  .contains("object=string,")
                                  .contains("map={key=value},")
                                  .contains("object[]=[1, string, null],")
                                  .contains("int[]=[1, 2, 3],")
                                  .contains("boolean[]=[true],")
                                  .contains("char[]=[1, 2]");
}