Fix FileSnapshotTests for filesystem with high timestamp resolution

When filesystem timestamp resolution is very high some tests don't work
since runtime of the test setup is too long to reach a racily clean
FileSnapshot. Hence skip these tests when timestamp resolution is higher
than 10 millisecond.

Change-Id: Ie47dd10eda22037b5c1ebff6b6becce0654ea807
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/FileSnapshotTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/FileSnapshotTest.java
index f228fb330b008053a2ff1fe8968e78d80f051250..1dea47084806a1ba1865594f2f9ddcd94328adc3 100644 (file)
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/FileSnapshotTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/FileSnapshotTest.java
@@ -52,7 +52,9 @@ import java.nio.file.Path;
 import java.nio.file.StandardCopyOption;
 import java.nio.file.StandardOpenOption;
 import java.nio.file.attribute.FileTime;
+import java.time.Duration;
 import java.time.Instant;
+import java.util.concurrent.TimeUnit;
 
 import org.eclipse.jgit.util.FS;
 import org.eclipse.jgit.util.FileUtils;
@@ -66,12 +68,14 @@ public class FileSnapshotTest {
 
        private Path trash;
 
+       private Duration fsTimerResolution;
+
        @Before
        public void setUp() throws Exception {
                trash = Files.createTempDirectory("tmp_");
                // measure timer resolution before the test to avoid time critical tests
                // are affected by time needed for measurement
-               FS.getFsTimerResolution(trash.getParent());
+               fsTimerResolution = FS.getFsTimerResolution(trash.getParent());
        }
 
        @Before
@@ -114,10 +118,14 @@ public class FileSnapshotTest {
         */
        @Test
        public void testNewFileWithWait() throws Exception {
+               // if filesystem timestamp resolution is high the snapshot won't be
+               // racily clean
+               Assume.assumeTrue(
+                               fsTimerResolution.compareTo(Duration.ofMillis(10)) > 0);
                Path f1 = createFile("newfile");
                waitNextTick(f1);
                FileSnapshot save = FileSnapshot.save(f1.toFile());
-               Thread.sleep(1500);
+               TimeUnit.NANOSECONDS.sleep(fsTimerResolution.dividedBy(2).toNanos());
                assertTrue(save.isModified(f1.toFile()));
        }
 
@@ -128,6 +136,10 @@ public class FileSnapshotTest {
         */
        @Test
        public void testNewFileNoWait() throws Exception {
+               // if filesystem timestamp resolution is high the snapshot won't be
+               // racily clean
+               Assume.assumeTrue(
+                               fsTimerResolution.compareTo(Duration.ofMillis(10)) > 0);
                Path f1 = createFile("newfile");
                FileSnapshot save = FileSnapshot.save(f1.toFile());
                assertTrue(save.isModified(f1.toFile()));