Document how --releasever, --releasever_{major,minor} affect each other

Upstream commit: e931960

Author: evan-goode

dnf/conf/config.py

@@ -425,6 +425,12 @@ def releasever(self):
     @releasever.setter
     def releasever(self, val):
         # :api
+        """
+        Sets the releasever variable and sets releasever_major and
+        releasever_minor accordingly. releasever_major is set to the part of
+        $releasever before the first ".". releasever_minor is set to the part
+        after the first ".".
+        """
         if val is None:
             self.substitutions.pop('releasever', None)
             return
@@ -438,6 +444,11 @@ def releasever_major(self):
     @releasever_major.setter
     def releasever_major(self, val):
         # :api
+        """
+        Override the releasever_major variable, which is usually derived from
+        the releasever variable. This setter does not update the value of
+        $releasever.
+        """
         if val is None:
             self.substitutions.pop('releasever_major', None)
             return
@@ -446,6 +457,11 @@ def releasever_major(self, val):
     @property
     def releasever_minor(self):
         # :api
+        """
+        Override the releasever_minor variable, which is usually derived from
+        the releasever variable. This setter does not update the value of
+        $releasever.
+        """
         return self.substitutions.get('releasever_minor')
 
     @releasever_minor.setter

doc/command_ref.rst

@@ -337,10 +337,12 @@ Options
 ``--releasever_major=<major version>``
     Override the releasever_major variable, which is usually automatically
     detected or taken from the part of ``$releasever`` before the first ``.``.
+    This option does not affect the ``$releasever`` variable.
 
 ``--releasever_minor=<minor version>``
     Override the releasever_minor variable, which is usually automatically
     detected or taken from the part of ``$releasever`` after the first ``.``.
+    This option does not affect the ``$releasever`` variable.
 
 .. _repofrompath_options-label:
 

tests/test_config.py

@@ -149,15 +149,18 @@ def test_ranges(self):
     def test_releasever_major_minor(self):
         conf = Conf()
         conf.releasever = '1.2'
+        self.assertEqual(conf.releasever, '1.2')
         self.assertEqual(conf.releasever_major, '1')
         self.assertEqual(conf.releasever_minor, '2')
 
         # override releasever_major
         conf.releasever_major = '3'
+        self.assertEqual(conf.releasever, '1.2')
         self.assertEqual(conf.releasever_major, '3')
         self.assertEqual(conf.releasever_minor, '2')
 
         # override releasever_minor
         conf.releasever_minor = '4'
+        self.assertEqual(conf.releasever, '1.2')
         self.assertEqual(conf.releasever_major, '3')
         self.assertEqual(conf.releasever_minor, '4')