Merge pull request #2824 from daniel-beck/JENKINS-43228

[FIX JENKINS-43228] Consider time zone for cron validation

core/src/main/java/hudson/scheduler/CronTab.java

@@ -532,4 +532,17 @@ public final class CronTab {
             return null;
         }
     }
+
+    /**
+     * Returns the configured time zone, or null if none is configured
+     *
+     * @return the configured time zone, or null if none is configured
+     * @since TODO
+     */
+    @CheckForNull public TimeZone getTimeZone() {
+        if (this.specTimezone == null) {
+            return null;
+        }
+        return TimeZone.getTimeZone(this.specTimezone);
+    }
 }

core/src/main/java/hudson/scheduler/CronTabList.java

@@ -131,7 +131,7 @@ public final class CronTabList {
     public @CheckForNull Calendar previous() {
         Calendar nearest = null;
         for (CronTab tab : tabs) {
-            Calendar scheduled = tab.floor(Calendar.getInstance());
+            Calendar scheduled = tab.floor(tab.getTimeZone() == null ? Calendar.getInstance() : Calendar.getInstance(tab.getTimeZone()));
             if (nearest == null || nearest.before(scheduled)) {
                 nearest = scheduled;
             }
@@ -143,7 +143,7 @@ public final class CronTabList {
     public @CheckForNull Calendar next() {
         Calendar nearest = null;
         for (CronTab tab : tabs) {
-            Calendar scheduled = tab.ceil(Calendar.getInstance());
+            Calendar scheduled = tab.ceil(tab.getTimeZone() == null ? Calendar.getInstance() : Calendar.getInstance(tab.getTimeZone()));
             if (nearest == null || nearest.after(scheduled)) {
                 nearest = scheduled;
             }

core/src/test/java/hudson/triggers/TimerTriggerTest.java

@@ -24,9 +24,14 @@
 package hudson.triggers;
 
 import antlr.ANTLRException;
+import hudson.scheduler.CronTabList;
+import hudson.scheduler.Hash;
+import org.junit.Assert;
 import org.junit.Test;
 import org.jvnet.hudson.test.Issue;
 
+import java.util.TimeZone;
+
 /**
  * @author Kanstantsin Shautsou
  */
@@ -36,4 +41,22 @@ public class TimerTriggerTest {
     public void testNoNPE() throws ANTLRException {
         new TimerTrigger("").run();
     }
+
+    @Issue("JENKINS-43328")
+    @Test
+    public void testTimeZoneOffset() throws Exception {
+        TimeZone defaultTz = TimeZone.getDefault();
+        TimeZone.setDefault(TimeZone.getTimeZone("Europe/Berlin"));
+        try {
+            String cron = "TZ=GMT\nH 0 * * *";
+            CronTabList ctl = CronTabList.create(cron, Hash.from("whatever"));
+            Assert.assertEquals("previous occurrence is in GMT", "GMT", ctl.previous().getTimeZone().getID());
+
+            cron = "TZ=America/Denver\nH 0 * * *";
+            ctl = CronTabList.create(cron, Hash.from("whatever"));
+            Assert.assertEquals("next occurrence is in America/Denver", "America/Denver", ctl.next().getTimeZone().getID());
+        } finally {
+            TimeZone.setDefault(defaultTz);
+        }
+    }
 }