fix: Initialize DirHandle generation correctly to prevent spurious invalidations

The tests were failing because new DirHandles started with generation=0,
but the directory might already have a non-zero generation from prior
modifications. This caused the handle to immediately think it was out
of date and reset its position, leading to missing entries in readdir.

Changes:
- Initialize generation when creating new DirHandles
- Reset generation to current when seeking to offset 0
- Ensure consistent generation tracking across all handle creation paths

This fixes the test failures where directory listings were returning
incomplete results.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: ovaistariq

core/cluster_fs.go

@@ -430,6 +430,7 @@ func (fs *ClusterFs) readDir(handleId fuseops.HandleID, offset fuseops.DirOffset
 		dh.lastExternalOffset = 0
 		dh.lastInternalOffset = 0
 		dh.lastName = ""
+		dh.generation = atomic.LoadUint64(&dh.inode.dir.generation)
 	}
 
 	for {

core/cluster_fs_fuse.go

@@ -550,7 +550,10 @@ func (fs *ClusterFsFuse) OpenDir(ctx context.Context, op *fuseops.OpenDirOp) (er
 
 			// 2nd phase
 			fs.Goofys.mu.Lock()
-			dh := &DirHandle{inode: inode}
+			dh := &DirHandle{
+				inode:      inode,
+				generation: atomic.LoadUint64(&inode.dir.generation),
+			}
 			fs.Goofys.dirHandles[fuseops.HandleID(resp.HandleId)] = dh
 			fs.Goofys.mu.Unlock()
 

core/dir.go

@@ -93,7 +93,10 @@ type DirHandle struct {
 }
 
 func NewDirHandle(inode *Inode) (dh *DirHandle) {
-	dh = &DirHandle{inode: inode}
+	dh = &DirHandle{
+		inode:      inode,
+		generation: atomic.LoadUint64(&inode.dir.generation),
+	}
 	return
 }
 
@@ -775,6 +778,7 @@ func (dh *DirHandle) Seek(newOffset fuseops.DirOffset) {
 		dh.lastExternalOffset = 0
 		dh.lastInternalOffset = 0
 		dh.lastName = ""
+		dh.generation = atomic.LoadUint64(&dh.inode.dir.generation)
 	}
 }