Add parameterized benchmark largeSerialFormat to test parser structure formatting scalability.

Author: DmitryNekrasov

benchmarks/src/jmh/kotlin/ParserStructureConcatBenchmark.kt

@@ -21,6 +21,30 @@ import java.util.concurrent.*
 @Fork(1)
 open class ParserStructureConcatBenchmark {
 
+    @Param("1", "2", "4", "8", "16")
+    var n = 0
+
+    @Benchmark
+    fun largeSerialFormat(blackhole: Blackhole) {
+        val format = LocalDateTime.Format {
+            repeat(n) {
+                year()
+                char('-')
+                monthNumber()
+                char('-')
+                day()
+                char(' ')
+                hour()
+                char(':')
+                minute()
+                char(':')
+                second()
+                char('_')
+            }
+        }
+        blackhole.consume(format)
+    }
+
     @Benchmark
     fun buildPythonDateTimeFormat(blackhole: Blackhole) {
         val v = LocalDateTime.Format {