Add formatCreationWithNestedAlternativeParsing benchmark to test complex parser structures

Author: DmitryNekrasov

benchmarks/src/jmh/kotlin/ParallelFormatBenchmark.kt

@@ -41,4 +41,48 @@ open class ParallelFormatBenchmark {
         }
         blackhole.consume(format)
     }
+
+    @Benchmark
+    fun formatCreationWithNestedAlternativeParsing(blackhole: Blackhole) {
+        val format = LocalDateTime.Format {
+            repeat(n) { index ->
+                alternativeParsing(
+                    { monthNumber(); char('-'); day() },
+                    { day(); char('/'); monthNumber() },
+                    primaryFormat = { year(); char('-'); monthNumber(); char('-'); day() }
+                )
+
+                if (index % 2 == 0) {
+                    alternativeParsing(
+                        {
+                            alternativeParsing(
+                                { hour(); char(':'); minute() },
+                                { minute(); char(':'); second() },
+                                primaryFormat = { hour(); char(':'); minute(); char(':'); second() }
+                            )
+                        },
+                        primaryFormat = {
+                            year(); char('-'); monthNumber(); char('-'); day()
+                            char('T')
+                            hour(); char(':'); minute(); char(':'); second()
+                        }
+                    )
+                }
+
+                char('|')
+                if (index % 3 == 0) {
+                    char('|')
+                }
+
+                if (index < 8) {
+                    alternativeParsing(
+                        { char('Z') },
+                        { char('+'); hour(); char(':'); minute() },
+                        primaryFormat = { char('-'); hour(); char(':'); minute() }
+                    )
+                }
+            }
+        }
+        blackhole.consume(format)
+    }
 }