Fix S3 delete for non-empty directory markers (#8740)

* Fix S3 delete for non-empty directory markers

* Address review feedback on directory marker deletes

* Stabilize FUSE concurrent directory operations

weed/mount/filehandle_test.go

@@ -0,0 +1,52 @@
+package mount
+
+import (
+	"testing"
+
+	"github.com/seaweedfs/seaweedfs/weed/util"
+)
+
+func TestFileHandleFullPathFallsBackAfterForget(t *testing.T) {
+	wfs := &WFS{
+		inodeToPath: NewInodeToPath(util.FullPath("/"), 0),
+	}
+
+	fullPath := util.FullPath("/worker_0/subdir_0/test.txt")
+	inode := wfs.inodeToPath.Lookup(fullPath, 1, false, false, 0, true)
+
+	fh := &FileHandle{
+		inode: inode,
+		wfs:   wfs,
+	}
+	fh.RememberPath(fullPath)
+
+	wfs.inodeToPath.Forget(inode, 1, nil)
+
+	if got := fh.FullPath(); got != fullPath {
+		t.Fatalf("FullPath() after forget = %q, want %q", got, fullPath)
+	}
+}
+
+func TestFileHandleFullPathUsesSavedRenamePathAfterForget(t *testing.T) {
+	wfs := &WFS{
+		inodeToPath: NewInodeToPath(util.FullPath("/"), 0),
+	}
+
+	oldPath := util.FullPath("/worker_0/subdir_0/test.txt")
+	newPath := util.FullPath("/worker_0/subdir_1/test.txt")
+	inode := wfs.inodeToPath.Lookup(oldPath, 1, false, false, 0, true)
+
+	fh := &FileHandle{
+		inode: inode,
+		wfs:   wfs,
+	}
+	fh.RememberPath(oldPath)
+
+	wfs.inodeToPath.MovePath(oldPath, newPath)
+	fh.RememberPath(newPath)
+	wfs.inodeToPath.Forget(inode, 1, nil)
+
+	if got := fh.FullPath(); got != newPath {
+		t.Fatalf("FullPath() after rename+forget = %q, want %q", got, newPath)
+	}
+}