From 356750cf50db14dd90d9d22a1c08d4ac04801d2b Mon Sep 17 00:00:00 2001
From: John Stilley <1831479+john-science@users.noreply.github.com>
Date: Mon, 30 Sep 2024 17:02:40 -0700
Subject: [PATCH] Alphabetizing Flags.toString results (#1912)

---
 armi/reactor/flags.py            |  3 ++-
 armi/reactor/tests/test_flags.py |  8 ++++++++
 doc/release/0.4.rst              | 13 +++++--------
 3 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/armi/reactor/flags.py b/armi/reactor/flags.py
index 14bcff7e8..3386772f9 100644
--- a/armi/reactor/flags.py
+++ b/armi/reactor/flags.py
@@ -185,7 +185,8 @@ def _toString(cls, typeSpec):
     -----
     This converts a flag from ``Flags.A|B`` to ``'A B'``
     """
-    return str(typeSpec).split("{}.".format(cls.__name__))[1].replace("|", " ")
+    strings = str(typeSpec).split("{}.".format(cls.__name__))[1]
+    return " ".join(sorted(strings.split("|")))
 
 
 class Flags(Flag):
diff --git a/armi/reactor/tests/test_flags.py b/armi/reactor/tests/test_flags.py
index bbc4c1cb8..7155cae95 100644
--- a/armi/reactor/tests/test_flags.py
+++ b/armi/reactor/tests/test_flags.py
@@ -38,6 +38,14 @@ def test_flagsToAndFromString(self):
         self.assertEqual(flags.Flags.toString(f), "FUEL")
         self.assertEqual(f, flags.Flags.fromString("FUEL"))
 
+    def test_toStringAlphabetical(self):
+        """Ensure that, for multiple flags, toString() returns them in alphabetical order."""
+        flagz = flags.Flags.AXIAL | flags.Flags.LOWER
+        self.assertEqual(flags.Flags.toString(flagz), "AXIAL LOWER")
+
+        flagz = flags.Flags.LOWER | flags.Flags.AXIAL
+        self.assertEqual(flags.Flags.toString(flagz), "AXIAL LOWER")
+
     def test_fromStringStrict(self):
         self._help_fromString(flags.Flags.fromString)
         with self.assertRaises(flags.InvalidFlagsError):
diff --git a/doc/release/0.4.rst b/doc/release/0.4.rst
index 45f7dba34..cda3e8ffd 100644
--- a/doc/release/0.4.rst
+++ b/doc/release/0.4.rst
@@ -14,17 +14,15 @@ New Features
 #. Allow merging a component with zero area into another component (`PR#1858 <https://github.com/terrapower/armi/pull/1858>`_)
 #. Provide utilities for determining location of a rotated object in a hexagonal lattice (``getIndexOfRotatedCell``). (`PR#1846 <https://github.com/terrapower/armi/1846`)
 #. Allow merging a component with zero area into another component. (`PR#1858 <https://github.com/terrapower/armi/pull/1858>`_)
-#. Provide ``Parameter.hasCategory`` for quickly checking if a parameter is defined with a given category.
-   (`PR#1899 <https://github.com/terrapower/armi/pull/1899>`_)
-#. Provide ``ParameterCollection.where`` for efficient iteration over parameters who's definition.
-   matches a given condition. (`PR#1899 <https://github.com/terrapower/armi/pull/1899>`_)
-#. Plugins can provide the ``getAxialExpansionChanger`` hook to customize axial expansion.
-   (`PR#1870 <https://github.com/terrapower/armi/pull/1870`_)
+#. Provide ``Parameter.hasCategory`` for quickly checking if a parameter is defined with a given category. (`PR#1899 <https://github.com/terrapower/armi/pull/1899>`_)
+#. Provide ``ParameterCollection.where`` for efficient iteration over parameters who's definition matches a given condition. (`PR#1899 <https://github.com/terrapower/armi/pull/1899>`_)
+#. Plugins can provide the ``getAxialExpansionChanger`` hook to customize axial expansion. (`PR#1870 <https://github.com/terrapower/armi/pull/1870`_)
 #. TBD
 
 API Changes
 -----------
 #. Removing flags ``CORE`` and ``REACTOR``. (`PR#1835 <https://github.com/terrapower/armi/pull/1835>`_)
+#. Alphabetizing ``Flags.toString()`` results. (`PR#1912 <https://github.com/terrapower/armi/pull/1912>`_)
 #. Moving ``settingsValidation`` from ``operators`` to ``settings``. (`PR#1895 <https://github.com/terrapower/armi/pull/1895>`_)
 #. Removing deprecated method ``prepSearch``. (`PR#1845 <https://github.com/terrapower/armi/pull/1845>`_)
 #. Removing unused function ``SkippingXsGen_BuChangedLessThanTolerance``. (`PR#1845 <https://github.com/terrapower/armi/pull/1845>`_)
@@ -42,8 +40,7 @@ Bug Fixes
 #. Changed data type of ``thKernel`` setting from ``bool`` to ``str`` in ``ThermalHydraulicsPlugin``. (`PR#1855 <https://github.com/terrapower/armi/pull/1855>`_)
 #. Rotate hexagonal assembly patches correctly on facemap plots. (`PR#1883 <https://github.com/terrapower/armi/pull/1883>`_)
 #. Update height of fluid components after axial expansion (`PR#1828 <https://github.com/terrapower/armi/pull/1828>`_)
-#. Material theoretical density is serialized to and read from database.
-   (`PR#1852 <https://github.com/terrapower/armi/pull/1852>`_)
+#. Material theoretical density is serialized to and read from database. (`PR#1852 <https://github.com/terrapower/armi/pull/1852>`_)
 #. TBD
 
 Quality Work