Fix bug in _harmonize_inputs_to_dict (#563)

Author: gauravmanmode

src/optimagic/visualization/history_plots.py

@@ -172,7 +172,7 @@ def _harmonize_inputs_to_dict(results, names):
     if not isinstance(names, list) and names is not None:
         names = [names]
 
-    if isinstance(results, OptimizeResult):
+    if isinstance(results, (OptimizeResult, str, Path)):
         results = [results]
 
     if names is not None and len(names) != len(results):

tests/optimagic/visualization/test_history_plots.py

@@ -1,4 +1,5 @@
 import itertools
+from pathlib import Path
 
 import numpy as np
 import pytest
@@ -126,6 +127,7 @@ def test_criterion_plot_different_input_types():
     criterion_plot(results, stack_multistart=True)
     criterion_plot(results, monotone=True, stack_multistart=True)
     criterion_plot(results, show_exploration=True)
+    criterion_plot("test.db")
 
 
 def test_criterion_plot_wrong_inputs():
@@ -176,3 +178,12 @@ def test_harmonize_inputs_to_dict_invalid_names():
     names = ["a", "b"]
     with pytest.raises(ValueError):
         _harmonize_inputs_to_dict(results=results, names=names)
+
+
+def test_harmonize_inputs_to_dict_str_input():
+    assert _harmonize_inputs_to_dict(results="test.db", names=None) == {"0": "test.db"}
+
+
+def test_harmonize_inputs_to_dict_path_input():
+    path = Path("test.db")
+    assert _harmonize_inputs_to_dict(results=path, names=None) == {"0": path}