Locale Timestamp (#170)

* Specify Locale.ROOT when calling dateTimeNowString()

* Add test

* Add comment

* Update test

Author: dennisdeng2002

core/src/main/java/com/segment/analytics/kotlin/core/utilities/DateTimeUtils.kt

@@ -12,8 +12,10 @@ import java.util.*
  * dateTimeNowString(): 2023-04-19T04:03:46.880Z
  */
 fun dateTimeNowString(): String {
-    val sdf = SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'.'Szzz")
+    // Note, we should specify locale = Locale.ROOT, otherwise the timestamp returned will use
+    // the default locale, which may not be what we want.
+    val sdf = SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'.'Szzz", Locale.ROOT)
     val utc = TimeZone.getTimeZone("UTC");
     sdf.timeZone = utc;
     return sdf.format(Date()).replace("UTC", "Z")
-}
+}

core/src/test/kotlin/com/segment/analytics/kotlin/core/utilities/DateTimeUtilsTest.kt

@@ -0,0 +1,15 @@
+package com.segment.analytics.kotlin.core.utilities
+
+import org.junit.jupiter.api.Assertions.assertNotNull
+import org.junit.jupiter.api.Test
+import java.time.format.DateTimeFormatter.ISO_DATE_TIME
+
+class DateTimeUtilsTest {
+
+    @Test
+    fun `dateTimeNowString() produces a string in the correct ISO8601 format`() {
+        val dateTimeNowString = dateTimeNowString()
+        val date = ISO_DATE_TIME.parse(dateTimeNowString)
+        assertNotNull(date)
+    }
+}