chore(sdk): add missing tests for std.Duration (#4382)

Closes #2962

*By submitting this pull request, I confirm that my contribution is made under the terms of the [Wing Cloud Contribution License](https://github.com/winglang/wing/blob/main/CONTRIBUTION_LICENSE.md)*.

examples/tests/sdk_tests/std/duration.test.w

@@ -56,6 +56,94 @@ test "duration" {
   assert(3600s == 1h);
   assert(86400s == 1d);
   assert(31536000s == 1y);
-}
 
-// TODO: https://github.com/winglang/wing/issues/2785
+  // Conversion from milliseconds to all units
+  assert(duration.fromMilliseconds(1000).seconds == 1);
+  assert(duration.fromMilliseconds(1000).minutes == 1s.minutes);
+  assert(duration.fromMilliseconds(1000).hours == 1s.hours);
+  assert(duration.fromMilliseconds(1000).days == 1s.days);
+  assert(duration.fromMilliseconds(1000).months == 1s.months);
+  assert(duration.fromMilliseconds(1000).years == 1s.years);
+
+  // Conversion from seconds to all units
+  assert(duration.fromSeconds(60).milliseconds == 60s.milliseconds);
+  assert(duration.fromSeconds(60).minutes == 1);
+  assert(duration.fromSeconds(60).hours == 1m.hours);
+  assert(duration.fromSeconds(60).days == 1m.days);
+  assert(duration.fromSeconds(60).months == 1m.months);
+  assert(duration.fromSeconds(60).years == 1m.years);
+
+  // Conversion from minutes to all units
+  assert(duration.fromMinutes(60).milliseconds == 60m.milliseconds);
+  assert(duration.fromMinutes(60).seconds == 60m.seconds);
+  assert(duration.fromMinutes(60).hours == 1);
+  assert(duration.fromMinutes(60).days == 1h.days);
+  assert(duration.fromMinutes(60).months == 1h.months);
+  assert(duration.fromMinutes(60).years == 1h.years);
+
+  // Conversion from hours to all units
+  assert(duration.fromHours(24).milliseconds == 24h.milliseconds);
+  assert(duration.fromHours(24).seconds == 24h.seconds);
+  assert(duration.fromHours(24).minutes == 24h.minutes);
+  assert(duration.fromHours(24).days == 1);
+  assert(duration.fromHours(24).months == 1d.months);
+  assert(duration.fromHours(24).years == 1d.years);
+
+  // Conversion from days to all units
+  assert(duration.fromDays(365).milliseconds == 365d.milliseconds);
+  assert(duration.fromDays(365).seconds == 365d.seconds);
+  assert(duration.fromDays(365).minutes == 365d.minutes);
+  assert(duration.fromDays(365).hours == 365d.hours);
+  assert(duration.fromDays(365).months == 12);
+  assert(duration.fromDays(365).years == 1);
+
+  // Conversion from months to all units
+  assert(duration.fromMonths(12).milliseconds == 12mo.milliseconds);
+  assert(duration.fromMonths(12).seconds == 12mo.seconds);
+  assert(duration.fromMonths(12).minutes == 12mo.minutes);
+  assert(duration.fromMonths(12).hours == 12mo.hours);
+  assert(duration.fromMonths(12).days == 12mo.days);
+  assert(duration.fromMonths(12).years == 1);
+
+  // Conversion from years to all units
+  assert(duration.fromYears(1).milliseconds == 1y.milliseconds);
+  assert(duration.fromYears(1).seconds == 1y.seconds);
+  assert(duration.fromYears(1).minutes == 1y.minutes);
+  assert(duration.fromYears(1).hours == 1y.hours);
+  assert(duration.fromYears(1).days == 1y.days);
+  assert(duration.fromYears(1).months == 1y.months);
+
+  // Testing negative values
+  assert(-12ms.seconds == -12 / 1000);
+  assert(-12s.seconds == -12);
+  assert(-12m.seconds == -12 * 60);
+  assert(-12h.seconds == -12 * 60 * 60);
+  assert(-12d.seconds == -12 * 60 * 60 * 24);
+  assert(-12mo.seconds == (-12 * 60 * 60 * 24 * 365) / 12);
+  assert(-12y.seconds == -12 * 60 * 60 * 24 * 365);
+
+  assert(duration.fromMilliseconds(-10).seconds == -10ms.seconds);
+  assert(duration.fromMinutes(-10).seconds == -10m.seconds);
+  assert(duration.fromSeconds(-10).seconds == -10s.seconds);
+  assert(duration.fromHours(-10).seconds == -10h.seconds);
+  assert(duration.fromDays(-10).seconds == -10d.seconds);
+  assert(duration.fromMonths(-10).seconds == -10mo.seconds);
+  assert(duration.fromYears(-10).seconds == -10y.seconds);
+
+  // Testing zero
+  assert(0ms.seconds == 0);
+  assert(0s.seconds == 0);
+  assert(0m.seconds == 0);
+  assert(0h.seconds == 0);
+  assert(0d.seconds == 0);
+  assert(0mo.seconds == 0);
+  assert(0y.seconds == 0);
+
+  assert(duration.fromMilliseconds(0).seconds == 0ms.seconds);
+  assert(duration.fromMinutes(0).seconds == 0m.seconds);
+  assert(duration.fromSeconds(0).seconds == 0s.seconds);
+  assert(duration.fromHours(0).seconds == 0h.seconds);
+  assert(duration.fromDays(0).seconds == 0d.seconds);
+  assert(duration.fromMonths(0).seconds == 0mo.seconds);
+  assert(duration.fromYears(0).seconds == 0y.seconds);
+}