fix of #27

src/commonMain/kotlin/dev/inmo/krontab/StringParser.kt

@@ -57,13 +57,13 @@ typealias KrontabTemplate = String
  * * "0/5,L * * * *" for every five seconds triggering and on 59 second
  * * "0/15 30 * * *" for every 15th seconds in a half of each hour
  * * "0/15 30 * * * 500ms" for every 15th seconds in a half of each hour when milliseconds equal to 500
- * * "1 2 3 F,4,L 5" for triggering in near first second of second minute of third hour of fourth day of may
+ * * "1 2 3 F,4,L 5" for triggering in near first second of second minute of third hour of first, fifth and last days of may
- * * "1 2 3 F,4,L 5 60o" for triggering in near first second of second minute of third hour of fourth day of may with timezone UTC+01:00
+ * * "1 2 3 F,4,L 5 60o" for triggering in near first second of second minute of third hour of first, fifth and last days of may with timezone UTC+01:00
- * * "1 2 3 F,4,L 5 60o 0-2w" for triggering in near first second of second minute of third hour of fourth day of may in case if it will be in Sunday-Tuesday week days with timezone UTC+01:00
+ * * "1 2 3 F,4,L 5 60o 0-2w" for triggering in near first second of second minute of third hour of first, fifth and last days of may in case if it will be in Sunday-Tuesday week days with timezone UTC+01:00
- * * "1 2 3 F,4,L 5 2021" for triggering in near first second of second minute of third hour of fourth day of may of 2021st year
+ * * "1 2 3 F,4,L 5 2021" for triggering in near first second of second minute of third hour of first, fifth and last days of may of 2021st year
- * * "1 2 3 F,4,L 5 2021 60o" for triggering in near first second of second minute of third hour of fourth day of may of 2021st year with timezone UTC+01:00
+ * * "1 2 3 F,4,L 5 2021 60o" for triggering in near first second of second minute of third hour of first, fifth and last days of may of 2021st year with timezone UTC+01:00
- * * "1 2 3 F,4,L 5 2021 60o 0-2w" for triggering in near first second of second minute of third hour of fourth day of may of 2021st year if it will be in Sunday-Tuesday week days with timezone UTC+01:00
+ * * "1 2 3 F,4,L 5 2021 60o 0-2w" for triggering in near first second of second minute of third hour of first, fifth and last days of may of 2021st year if it will be in Sunday-Tuesday week days with timezone UTC+01:00
- * * "1 2 3 F,4,L 5 2021 60o 0-2w 500ms" for triggering in near first second of second minute of third hour of fourth day of may of 2021st year if it will be in Sunday-Tuesday week days with timezone UTC+01:00 when milliseconds will be equal to 500
+ * * "1 2 3 F,4,L 5 2021 60o 0-2w 500ms" for triggering in near first second of second minute of third hour of first, fifth and last days of may of 2021st year if it will be in Sunday-Tuesday week days with timezone UTC+01:00 when milliseconds will be equal to 500
  *
  * @return In case when offset parameter is absent in [incoming] will be used [createSimpleScheduler] method and
  * returned [CronDateTimeScheduler]. In case when offset parameter there is in [incoming] [KrontabTemplate] will be used

src/commonMain/kotlin/dev/inmo/krontab/internal/CronDateTime.kt

@@ -8,7 +8,7 @@ import dev.inmo.krontab.KronScheduler
  * @param daysOfWeek 0-6
  * @param years any int
  * @param months 0-11
- * @param daysOfMonth 0-31
+ * @param daysOfMonth 0-30
  * @param hours 0-23
  * @param minutes 0-59
  * @param seconds 0-59

src/commonMain/kotlin/dev/inmo/krontab/internal/NearDateTimeCalculator.kt

@@ -103,12 +103,13 @@ internal fun NearDateTimeCalculatorDays(
     times,
     { it.dayOfMonth.toByte() },
     { dateTime, newOne ->
-        (if (newOne < dateTime.dayOfMonth) {
+        val dateTime = (if (newOne < dateTime.dayOfMonth) {
             dateTime.plus(1.months)
         } else {
             dateTime
-        }).copy(
+        })
-            dayOfMonth = min(dateTime.month.days(dateTime.year), newOne.toInt() + 1), // index1
+        dateTime.copy(
+            dayOfMonth = min(dateTime.month.days(dateTime.year) - 1, newOne.toInt()), // index1
             hour = 0,
             minute = 0,
             second = 0,

src/commonTest/kotlin/dev/inmo/krontab/utils/InfinityLoopCheckTest.kt

@@ -0,0 +1,14 @@
+package dev.inmo.krontab.utils
+
+import dev.inmo.krontab.buildSchedule
+import kotlin.test.Test
+import kotlin.test.assertNotNull
+
+class InfinityLoopCheckTest {
+    @Test
+    fun absenceOfInfinityLoopCheckTest() {
+        runTest {
+            assertNotNull(buildSchedule("0 0 0 1 *").next())
+        }
+    }
+}