[9.0] test: Python 3.14 and matplotlib 3.11 compatibility in test suite

src/DIRAC/tests/Utilities/plots.py

@@ -1,6 +1,8 @@
 # pylint: disable=protected-access
+import glob
 import math
 import operator
+import os
 from functools import reduce
 
 from PIL import Image
@@ -24,3 +26,37 @@ def compare(file1Path, file2Path):
     h2 = image2.histogram()
     rms = math.sqrt(reduce(operator.add, map(lambda a, b: (a - b) ** 2, h1, h2)) / len(h1))
     return rms
+
+
+def referenceImages(directory, stem):
+    """Return every reference image available for a given plot.
+
+    The primary reference is ``<stem>.png``. Additional references may be added
+    as ``<stem>.<tag>.png`` (for example ``histogram1.mpl-3.10.png``) when a new
+    matplotlib version renders a plot slightly differently. Keeping several
+    references side by side means a plot is accepted against any supported
+    plotting-stack version, so an upgrade only needs an extra reference image
+    rather than replacing the existing one (which would break older versions).
+
+    :param str directory: Directory holding the reference images.
+    :param str stem: Base name of the plot, without extension.
+    :return: Sorted list of reference image paths.
+    """
+    paths = glob.glob(os.path.join(directory, f"{stem}.png"))
+    paths += glob.glob(os.path.join(directory, f"{stem}.*.png"))
+    return sorted(paths)
+
+
+def compareToReferences(generatedPath, referencePaths):
+    """Compare a generated plot against several candidate reference images.
+
+    :param str generatedPath: Path to the freshly generated plot.
+    :param referencePaths: Iterable of reference image paths to compare against.
+
+    :return: The smallest RMS obtained against any of the references, so a plot
+        is accepted as soon as it is identical (rms == 0.0) to one of them.
+    """
+    referencePaths = list(referencePaths)
+    if not referencePaths:
+        raise ValueError(f"No reference images provided for {generatedPath}")
+    return min(compare(generatedPath, reference) for reference in referencePaths)

tests/Integration/AccountingSystem/Test_Plots.py

@@ -11,7 +11,7 @@
     generateNoDataPlot,
     generatePiePlot,
 )
-from DIRAC.tests.Utilities.plots import compare
+from DIRAC.tests.Utilities.plots import compareToReferences, referenceImages
 
 plots_directory = os.path.join(os.path.dirname(__file__), "plots")
 filename = "plot.png"
@@ -25,21 +25,21 @@ def test_histogram():
     res = generateHistogram(filename, [2, 2, 3, 4, 5, 5], {})
     assert res["OK"] is True
 
-    res = compare(filename, os.path.join(plots_directory, "histogram1.png"))
+    res = compareToReferences(filename, referenceImages(plots_directory, "histogram1"))
     assert res == 0.0
 
     res = generateHistogram(
         filename, [{"a": [1, 2, 3, 1, 2, 2, 4, 2]}, {"b": [2, 2, 2, 4, 4, 1, 1]}], {"plot_grid": "2:1"}
     )
     assert res["OK"] is True
 
-    res = compare(filename, os.path.join(plots_directory, "histogram2.png"))
+    res = compareToReferences(filename, referenceImages(plots_directory, "histogram2"))
     assert res == 0.0
 
     res = generateHistogram(filename, [{"a": [1]}, {"b": [2, 3, 3, 5, 5]}], {})
     assert res["OK"] is True
 
-    res = compare(filename, os.path.join(plots_directory, "histogram3.png"))
+    res = compareToReferences(filename, referenceImages(plots_directory, "histogram3"))
     assert res == 0.0
 
 
@@ -50,7 +50,7 @@ def test_piechartplot():
     res = generatePiePlot(filename, {"a": 16.0, "b": 56.0, "c": 15, "d": 20}, {})
     assert res["OK"] is True
 
-    res = compare(filename, os.path.join(plots_directory, "piechart.png"))
+    res = compareToReferences(filename, referenceImages(plots_directory, "piechart"))
     assert res == 0.0
 
 
@@ -61,7 +61,7 @@ def test_nodataplot():
 
     res = generateNoDataPlot(filename, {}, {"title": "Test plot"})
     assert res["OK"] is True
-    res = compare(filename, os.path.join(plots_directory, "nodata.png"))
+    res = compareToReferences(filename, referenceImages(plots_directory, "nodata"))
     assert res == 0.0
 
 
@@ -74,5 +74,5 @@ def test_error():
     with open(filename, "wb") as out:
         out.write(res)
 
-    res = compare(filename, os.path.join(plots_directory, "error.png"))
+    res = compareToReferences(filename, referenceImages(plots_directory, "error"))
     assert res == 0.0

tests/Integration/DataManagementSystem/Test_UserMetadata.py

@@ -110,8 +110,8 @@ def test_metaIndex(self):
         # meta show
         result = self.fc.getMetadataFields()
         self.assertTrue(result["OK"])
-        self.assertDictContainsSubset({"MetaInt6": "INT"}, result["Value"]["FileMetaFields"])
-        self.assertDictContainsSubset({"TestDirectory6": "INT"}, result["Value"]["DirectoryMetaFields"])
+        self.assertLessEqual({"MetaInt6": "INT"}.items(), result["Value"]["FileMetaFields"].items())
+        self.assertLessEqual({"TestDirectory6": "INT"}.items(), result["Value"]["DirectoryMetaFields"].items())
 
         # meta set
         metaDict6 = {"MetaInt6": 13}
@@ -135,15 +135,15 @@ def test_metaIndex(self):
         # API call only
         result = self.fc.getFileUserMetadata(self.lfn5)
         self.assertTrue(result["OK"])
-        self.assertDictContainsSubset({"MetaInt6": 13}, result["Value"])
+        self.assertLessEqual({"MetaInt6": 13}.items(), result["Value"].items())
         # file: expect a failure
         result = self.fc.getDirectoryUserMetadata(self.lfn5)
         self.assertFalse(result["OK"])
 
         # directory
         result = self.fc.getDirectoryUserMetadata(self.dir5)
         self.assertTrue(result["OK"])
-        self.assertDictContainsSubset({"TestDirectory6": 126}, result["Value"])
+        self.assertLessEqual({"TestDirectory6": 126}.items(), result["Value"].items())
 
         # finally remove
         # meta remove lfn5 MetaInt6