fix: bugs occurring on daylight saving day (#291)

* fix: am/am being shown on daylight saving day

* fix: daylight saving hour wheel missing/extra hour

android/src/main/java/com/henninghall/date_picker/wheels/AmPmWheel.java

@@ -20,6 +20,9 @@ public class AmPmWheel extends Wheel {
     @Override
     public ArrayList<String> getValues() {
         Calendar cal = Calendar.getInstance();
+        // Getting the hours from a date that will never have daylight saving to be sure
+        // cal.add() will work properly.
+        cal.set(2000,0,0,0,0,0);
         ArrayList<String> values = new ArrayList<>();
 
         cal.set(Calendar.HOUR_OF_DAY, 0);

android/src/main/java/com/henninghall/date_picker/wheels/HourWheel.java

@@ -19,6 +19,10 @@ public class HourWheel extends Wheel {
     @Override
     public ArrayList<String> getValues() {
         Calendar cal = Calendar.getInstance();
+        // Getting the hours from a date that doesn't have daylight saving to be sure
+        // cal.add() will work properly.
+        cal.set(2000,0,0,0,0,0);
+
         ArrayList<String> values = new ArrayList<>();
         int numberOfHours = state.derived.usesAmPm() ? 12 : 24;
 

examples/manual-tests/daylight-saving.md

@@ -0,0 +1,19 @@
+# Daylight saving testing
+
+I haven't found an automatic way to change the time on the emulator to be able to run these tests automatically.
+
+## Test: AM/PM wheel should have proper values
+
+1. Set the timezone to GMT-07:00 Pacific Standard Time.
+1. Set the time to 2020-11-01
+1. Set 24h setting to false. (AM/PM=true)
+1. Go to time or datetime picker
+1. Expect: Both AM and PM being in visible in AM/PM wheel.
+
+## Test: Hour wheel should have proper values
+
+1. Set the timezone to GMT-07:00 Pacific Standard Time.
+1. Set the time to 2020-10-31 8:00 PM
+1. Set 24h setting to false. (AM/PM=true)
+1. Go to time or datetime picker.
+1. Expect: All hours to exist on hour wheel and no hour missing.