Update changelog and docs

CHANGELOG.md

@@ -1,8 +1,11 @@
 ### v2.1.4
-- Updated kotlin to 1.4.0.
+- Updated kotlin to 1.4.10.
 - Fixed layout issues with constrained width.
 - Fixed missing left and right margin in recurrence picker dialog for API <= 16.
 - Fixed dropdown widgets not wrapping width to content (introduced in 2.0.2).
+- Fixed some issues with weekly recurrence with no days set (aka on same day as start date).
+    - `Recurrence.toString()` now returns "on same day as start date" for this case.
+    - `RRuleFormatter` correctly formats this case which otherwise resulted in invalid RRule.
 
 ### v2.1.3
 - Introduced `rpListDialogMaxWidth` and `rpPickerDialogMaxWidth` attributes to limit the maximum size of dialogs on

lib/src/main/kotlin/com/maltaisn/recurpicker/Recurrence.kt

@@ -120,6 +120,8 @@ public class Recurrence private constructor(
      * Returns true only if recurrence happens on all of these days.
      * To get the number of days set use `Integer.bitCount(recurrence.byDay)  - 1`
      * (or `recurrence.byDay.countOneBits() - 1` in Kotlin).
+     * Note that if the weekly recurrence has no days set, meaning it happens on the same day as
+     * the start date's, this method will always return `false` since this day is unknown.
      * If period is [MONTHLY], checks if events happen on a certain day of the week specified
      * by a single flag set in [days].
      * @param days A bit field of [DaysOfWeek] values.
@@ -477,7 +479,8 @@ public class Recurrence private constructor(
         public const val FRIDAY: Int = 1 shl Calendar.FRIDAY
         public const val SATURDAY: Int = 1 shl Calendar.SATURDAY
 
-        public const val EVERY_DAY_OF_WEEK: Int = 0b11111111 // LSB is 1 to follow byDay layout so it can be used for comparison.
+        // LSB is 1 to follow byDay layout so it can be used for comparison.
+        public const val EVERY_DAY_OF_WEEK: Int = 0b11111111
 
         /** Date value used for no end date. */
         public const val DATE_NONE: Long = Long.MIN_VALUE