plots: handle NoRemoteError for dirs (#5976)

dvc/repo/plots/__init__.py

@@ -51,6 +51,7 @@ class Plots:
             }}}
         Data parsing is postponed, since it's affected by props.
         """
+        from dvc.config import NoRemoteError
         from dvc.fs.repo import RepoFileSystem
         from dvc.utils.collections import ensure_list
 
@@ -71,10 +72,21 @@ class Plots:
 
                 if fs.isdir(path_info):
                     plot_files = []
-                    for pi in fs.walk_files(path_info):
-                        plot_files.append(
-                            (pi, relpath(pi, self.repo.root_dir))
+                    try:
+                        for pi in fs.walk_files(path_info):
+                            plot_files.append(
+                                (pi, relpath(pi, self.repo.root_dir))
+                            )
+                    except NoRemoteError:
+                        logger.debug(
+                            (
+                                "Could not find cache for directory '%s' on "
+                                "'%s'. Files inside will not be plotted."
+                            ),
+                            path_info,
+                            rev,
                         )
+                        continue
                 else:
                     plot_files = [
                         (path_info, relpath(path_info, self.repo.root_dir))

tests/func/plots/test_show.py

@@ -828,6 +828,11 @@ def test_show_dir_plots(tmp_dir, dvc, run_copy_metrics):
     result = dvc.plots.show(targets=[p1])
     assert set(result.keys()) == {p1}
 
+    remove(dvc.odb.local.cache_dir)
+    remove(subdir)
+    with pytest.raises(NoMetricsParsedError):
+        dvc.plots.show()
+
 
 def test_ignore_binary_file(tmp_dir, dvc, run_copy_metrics):
     with open("file", "wb") as fobj: