Fix issue that MODIFIED events were issued for directories when auto-handling overflows

Author: sungshik

src/main/java/engineering/swat/watch/impl/overflows/MemorylessRescanner.java

@@ -89,14 +89,14 @@ public List<WatchEvent> getEvents() {
             return events;
         }
 
-        protected void addEvents(Path path, BasicFileAttributes attrs) {
+        private void addEvents(Path path, BasicFileAttributes attrs) {
             events.add(newEvent(WatchEvent.Kind.CREATED, path));
-            if (attrs.isDirectory() || attrs.size() > 0) {
+            if (attrs.isRegularFile() && attrs.size() > 0) {
                 events.add(newEvent(WatchEvent.Kind.MODIFIED, path));
             }
         }
 
-        protected WatchEvent newEvent(WatchEvent.Kind kind, Path fullPath) {
+        private WatchEvent newEvent(WatchEvent.Kind kind, Path fullPath) {
             var event = new WatchEvent(kind, fullPath);
             return watch.relativize(event);
         }

src/test/java/engineering/swat/watch/SingleDirectoryTests.java

@@ -157,7 +157,7 @@ void memorylessRescanOnOverflow() throws IOException, InterruptedException {
             await("Overflow should trigger created events")
                 .until(nCreated::get, Predicate.isEqual(6)); // 3 directories + 3 files
             await("Overflow should trigger modified events")
-                .until(nModified::get, Predicate.isEqual(5)); // 3 directories + 2 files (c.txt is still empty)
+                .until(nModified::get, Predicate.isEqual(2)); // 2 files (c.txt is still empty)
             await("Overflow should be visible to user-defined event handler")
                 .until(nOverflow::get, Predicate.isEqual(1));
         }