updating tests

src/corner/core.py

@@ -71,10 +71,11 @@ def corner_impl(
             # a default for when quantiles not supplied.
             title_quantiles = [0.16, 0.5, 0.84]
 
-    assert len(title_quantiles) == 3, (
-        "title_quantiles must contain three values -- "
-        "please pass a length-3 list or array using the title_quantiles kwarg"
-    )
+    if show_titles and len(title_quantiles) != 3:
+        raise ValueError(
+            "'title_quantiles' must contain exactly three values; "
+            "pass a length-3 list or array using the 'title_quantiles' argument"
+        )
 
     # Deal with 1D sample lists.
     xs = _parse_input(xs)

tests/test_corner.py

@@ -79,11 +79,39 @@ def test_labels():
 def test_quantiles():
     _run_corner(quantiles=[0.16, 0.5, 0.84])
 
+
 @image_comparison(
-    baseline_images=["quantiles"], remove_text=False extensions=["png"]
+    baseline_images=["title_quantiles"], remove_text=False, extensions=["png"]
 )
-def test_quantiles():
-    _run_corner(quantiles=[0.16, 0.5, 0.84], title_quantiles=None)
+def test_title_quantiles():
+    _run_corner(
+        quantiles=[0.16, 0.5, 0.84],
+        title_quantiles=[0.05, 0.5, 0.95],
+        show_titles=True,
+    )
+
+
+@image_comparison(
+    baseline_images=["title_quantiles_default"],
+    remove_text=False,
+    extensions=["png"],
+)
+def test_title_quantiles_default():
+    _run_corner(quantiles=[0.16, 0.5, 0.84], show_titles=True)
+
+
+@image_comparison(
+    baseline_images=["title_quantiles_raises"],
+    remove_text=False,
+    extensions=["png"],
+)
+def test_title_quantiles_raises():
+    with pytest.raises(ValueError):
+        _run_corner(quantiles=[0.05, 0.16, 0.5, 0.84, 0.95], show_titles=True)
+
+    # This one shouldn't raise since show_titles isn't provided
+    _run_corner(quantiles=[0.05, 0.16, 0.5, 0.84, 0.95])
+
 
 @image_comparison(
     baseline_images=["color"], remove_text=True, extensions=["png"]