feat(rt): add MIN/MAX values to Instant (#719)

Author: lauzadis

.changes/3c662a11-98c2-48cc-8cf5-ca0b293db1f9.json

@@ -0,0 +1,5 @@
+{
+  "id": "3c662a11-98c2-48cc-8cf5-ca0b293db1f9",
+  "type": "feature",
+  "description": "add `MIN` and `MAX` accessors for the Instant type"
+}

runtime/runtime-core/common/src/aws/smithy/kotlin/runtime/time/Instant.kt

@@ -68,6 +68,16 @@ public expect class Instant : Comparable<Instant> {
          * Create an [Instant] from the current system time
          */
         public fun now(): Instant
+
+        /**
+         * Create an [Instant] with the minimum possible value
+         */
+        public val MIN_VALUE: Instant
+
+        /**
+         * Create an [Instant] with the maximum possible value
+         */
+        public val MAX_VALUE: Instant
     }
 }
 

runtime/runtime-core/jvm/src/aws/smithy/kotlin/runtime/time/InstantJVM.kt

@@ -125,6 +125,16 @@ public actual class Instant(internal val value: jtInstant) : Comparable<Instant>
          * Create an [Instant] from the current system time
          */
         public actual fun now(): Instant = Instant(jtInstant.now())
+
+        /**
+         * Create an [Instant] with the minimum possible value
+         */
+        public actual val MIN_VALUE: Instant = Instant(jtInstant.MIN)
+
+        /**
+         * Create an [Instant] with the maximum possible value
+         */
+        public actual val MAX_VALUE: Instant = Instant(jtInstant.MAX)
     }
 }