fix(diff): show in "Not in cache" if dir entry is missing (#10844)

dvc/repo/diff.py

@@ -45,6 +45,10 @@ def _diff(old, new, data_keys, with_missing=False):
         with_renames=True,
         meta_cmp_key=meta_cmp_key,
         roots=data_keys,
+        # we need to get unknown and unchanged entries to tell whether
+        # the object is missing from the cache or not.
+        with_unknown=with_missing,
+        with_unchanged=with_missing,
     ):
         if (change.old and change.old.isdir and not change.old.hash_info) or (
             change.new and change.new.isdir and not change.new.hash_info

tests/func/test_diff.py

@@ -265,12 +265,22 @@ def test_diff_no_cache(tmp_dir, scm, dvc):
 
     remove(dvc.cache.local.path)
 
-    # invalidate_dir_info to force cache loading
-    dvc.cache.local._dir_info = {}
+    diff = dvc.diff("v1")
+    assert diff["added"] == []
+    assert diff["deleted"] == []
+    assert first(diff["modified"])["path"] == os.path.join("dir", "")
+    assert diff["renamed"] == []
+    assert diff["not in cache"] == [
+        {
+            "hash": "61d9c7f006e1ae7138fec5e574676ee2.dir",
+            "path": os.path.join("dir", ""),
+        }
+    ]
 
     diff = dvc.diff("v1", "v2")
     assert diff["added"] == []
     assert diff["deleted"] == []
+    assert diff["renamed"] == []
     assert first(diff["modified"])["path"] == os.path.join("dir", "")
     assert diff["not in cache"] == []