plugable: Move plugin base class and override logic to API

Each API object now maintains its own view of registered plugins. This change
removes the need to register plugin base classes.

This reverts commit 2db741e847.

https://fedorahosted.org/freeipa/ticket/3090
https://fedorahosted.org/freeipa/ticket/5073

Reviewed-By: Martin Babinsky <mbabinsk@redhat.com>

ipatests/test_ipalib/test_plugable.py

@@ -287,9 +287,9 @@ class test_Plugin(ClassChecker):
         assert e.argv == (paths.BIN_FALSE,)
 
 
-def test_Registry():
+def test_Registrar():
     """
-    Test the `ipalib.plugable.Registry` class
+    Test the `ipalib.plugable.Registrar` class
     """
     class Base1(object):
         pass
@@ -304,47 +304,8 @@ def test_Registry():
     class plugin3(Base3):
         pass
 
-    # Test creation of Registry:
-    register = plugable.Registry()
-    def b(klass):
-        register.base()(klass)
-    def r(klass, override=False):
-        register(override=override)(klass)
-
-    # Check that TypeError is raised trying to register base that isn't
-    # a class:
-    p = Base1()
-    e = raises(TypeError, b, p)
-    assert str(e) == 'plugin base must be a class; got %r' % p
-
-    # Check that base registration works
-    b(Base1)
-    i = tuple(register.iter(Base1))
-    assert len(i) == 1
-    assert i[0][0] is Base1
-    assert not i[0][1]
-
-    # Check that DuplicateError is raised trying to register exact class
-    # again:
-    e = raises(errors.PluginDuplicateError, b, Base1)
-    assert e.plugin is Base1
-
-    # Test that another base can be registered:
-    b(Base2)
-    i = tuple(register.iter(Base2))
-    assert len(i) == 1
-    assert i[0][0] is Base2
-    assert not i[0][1]
-
-    # Test iter:
-    i = tuple(register.iter(Base1, Base2))
-    assert len(i) == 2
-    assert i[0][0] is Base1
-    assert not i[0][1]
-    assert i[1][0] is Base2
-    assert not i[1][1]
-    e = raises(TypeError, register.iter, Base1, Base2, Base3)
-    assert str(e) == 'unknown plugin base %r' % Base3
+    # Test creation of Registrar:
+    r = plugable.Registrar()
 
     # Check that TypeError is raised trying to register something that isn't
     # a class:
@@ -352,59 +313,33 @@ def test_Registry():
     e = raises(TypeError, r, p)
     assert str(e) == 'plugin must be a class; got %r' % p
 
-    # Check that SubclassError is raised trying to register a class that is
-    # not a subclass of an allowed base:
-    e = raises(errors.PluginSubclassError, r, plugin3)
-    assert e.plugin is plugin3
-
     # Check that registration works
     r(plugin1)
-    i = tuple(register.iter(Base1))
-    assert len(i) == 1
-    assert i[0][0] is Base1
-    assert i[0][1] == {plugin1}
+    assert len(r) == 1
+    assert plugin1 in r
+    assert r[plugin1] == dict(override=False)
 
     # Check that DuplicateError is raised trying to register exact class
     # again:
     e = raises(errors.PluginDuplicateError, r, plugin1)
     assert e.plugin is plugin1
 
-    # Check that OverrideError is raised trying to register class with same
-    # name and same base:
+    # Check that overriding works
     orig1 = plugin1
     class base1_extended(Base1):
         pass
     class plugin1(base1_extended):  # pylint: disable=function-redefined
         pass
-    e = raises(errors.PluginOverrideError, r, plugin1)
-    assert e.base == 'Base1'
-    assert e.name == 'plugin1'
-    assert e.plugin is plugin1
-
-    # Check that overriding works
     r(plugin1, override=True)
-    i = tuple(register.iter(Base1))
-    assert len(i) == 1
-    assert i[0][0] is Base1
-    assert i[0][1] == {plugin1}
-
-    # Check that MissingOverrideError is raised trying to override a name
-    # not yet registerd:
-    e = raises(errors.PluginMissingOverrideError, r, plugin2, override=True)
-    assert e.base == 'Base2'
-    assert e.name == 'plugin2'
-    assert e.plugin is plugin2
+    assert len(r) == 2
+    assert plugin1 in r
+    assert r[plugin1] == dict(override=True)
 
     # Test that another plugin can be registered:
-    i = tuple(register.iter(Base2))
-    assert len(i) == 1
-    assert i[0][0] is Base2
-    assert not i[0][1]
     r(plugin2)
-    i = tuple(register.iter(Base2))
-    assert len(i) == 1
-    assert i[0][0] is Base2
-    assert i[0][1] == {plugin2}
+    assert len(r) == 3
+    assert plugin2 in r
+    assert r[plugin2] == dict(override=False)
 
     # Setup to test more registration:
     class plugin1a(Base1):
@@ -423,14 +358,6 @@ def test_Registry():
         pass
     r(plugin2b)
 
-    # Again test iter:
-    i = tuple(register.iter(Base1, Base2))
-    assert len(i) == 2
-    assert i[0][0] is Base1
-    assert i[0][1] == {plugin1, plugin1a, plugin1b}
-    assert i[1][0] is Base2
-    assert i[1][1] == {plugin2, plugin2a, plugin2b}
-
 
 class test_API(ClassChecker):
     """
@@ -445,15 +372,11 @@ class test_API(ClassChecker):
         """
         assert issubclass(plugable.API, plugable.ReadOnly)
 
-        register = plugable.Registry()
-
         # Setup the test bases, create the API:
-        @register.base()
         class base0(plugable.Plugin):
             def method(self, n):
                 return n
 
-        @register.base()
         class base1(plugable.Plugin):
             def method(self, n):
                 return n + 1
@@ -461,30 +384,31 @@ class test_API(ClassChecker):
         api = plugable.API([base0, base1], [])
         api.env.mode = 'unit_test'
         api.env.in_tree = True
+        r = api.register
 
-        @register()
         class base0_plugin0(base0):
             pass
+        r(base0_plugin0)
 
-        @register()
         class base0_plugin1(base0):
             pass
+        r(base0_plugin1)
 
-        @register()
         class base0_plugin2(base0):
             pass
+        r(base0_plugin2)
 
-        @register()
         class base1_plugin0(base1):
             pass
+        r(base1_plugin0)
 
-        @register()
         class base1_plugin1(base1):
             pass
+        r(base1_plugin1)
 
-        @register()
         class base1_plugin2(base1):
             pass
+        r(base1_plugin2)
 
         # Test API instance:
         assert api.isdone('bootstrap') is False