Force sorted order in plots rendering (#6601)

* Force sorted order in plots

* Fix type hint

* Fixed mypy

* Updates test_plots

* Removed reduntant test

* Removed unused import

dvc/render/utils.py

@@ -1,13 +1,14 @@
 import os.path
-from typing import Dict, List, Set
+from typing import Dict, List
 
 
-def get_files(data: Dict) -> Set:
+def get_files(data: Dict) -> List:
     files = set()
     for rev in data.keys():
         for file in data[rev].get("data", {}).keys():
             files.add(file)
-    return files
+    sorted_files = sorted(files)
+    return sorted_files
 
 
 def group_by_filename(plots_data: Dict) -> List[Dict]:

tests/unit/test_plots.py

@@ -28,9 +28,9 @@ def test_plots_order(tmp_dir, dvc):
             name="stage2",
         )
 
-    assert get_files(dvc.plots.show()) == {
+    assert get_files(dvc.plots.show()) == [
         "p.json",
-        os.path.join("sub", "p4.json"),
         "p1.json",
         os.path.join("sub", "p3.json"),
-    }
+        os.path.join("sub", "p4.json"),
+    ]