Make Python bindings more Pythonic

3 files changed, 44 insertions, 7 deletions

diff --git a/NEWS b/NEWS
index 41f286a..f1a93be 100644
--- a/NEWS
+++ b/NEWS
@@ -8,8 +8,9 @@ lilv (0.24.5) unstable;
   * Fix unit tests on Windows
   * Add more strict error detection when storing plugin state properties
   * Fix memory errors and Python 3.4+ compatibility in Python bindings
+  * Make Python bindings more Pythonic
 
- -- David Robillard <d@drobilla.net>  Mon, 21 Oct 2019 17:19:31 +0000
+ -- David Robillard <d@drobilla.net>  Mon, 21 Oct 2019 19:50:13 +0000
 
 lilv (0.24.4) stable;
 
diff --git a/bindings/python/lilv.py b/bindings/python/lilv.py
index 6fdd790..bfff997 100644
--- a/bindings/python/lilv.py
+++ b/bindings/python/lilv.py
@@ -946,9 +946,17 @@ class Plugins(Collection):
     def __getitem__(self, key):
         if type(key) == int:
             return super(Plugins, self).__getitem__(key)
-        return self.get_by_uri(key)
+
+        plugin = self.get_by_uri(key)
+        if plugin is None:
+            raise KeyError
+
+        return plugin
 
     def get_by_uri(self, uri):
+        if type(uri) == str:
+            uri = self.world.new_uri(uri)
+
         return Plugin.wrap(
             self.world, c.plugins_get_by_uri(self.collection, uri.node)
         )
@@ -985,9 +993,17 @@ class PluginClasses(Collection):
     def __getitem__(self, key):
         if type(key) == int:
             return super(PluginClasses, self).__getitem__(key)
-        return self.get_by_uri(key)
+
+        klass = self.get_by_uri(key)
+        if klass is None:
+            raise KeyError
+
+        return klass
 
     def get_by_uri(self, uri):
+        if type(uri) == str:
+            uri = self.world.new_uri(uri)
+
         plugin_class = c.plugin_classes_get_by_uri(self.collection, uri.node)
         return PluginClass(self.world, plugin_class) if plugin_class else None
 
@@ -1027,9 +1043,17 @@ class UIs(Collection):
     def __getitem__(self, key):
         if type(key) == int:
             return super(UIs, self).__getitem__(key)
-        return self.get_by_uri(key)
+
+        ui = self.get_by_uri(key)
+        if ui is None:
+            raise KeyError
+
+        return ui
 
     def get_by_uri(self, uri):
+        if type(uri) == str:
+            uri = self.world.new_uri(uri)
+
         ui = c.uis_get_by_uri(self.collection, uri.node)
         return UI(self.world, ui) if ui else None
 
@@ -1324,7 +1348,11 @@ class World(Structure):
 
     def new_uri(self, uri):
         """Create a new URI node."""
-        return Node.wrap(self, c.new_uri(self.world, uri))
+        c_node = c.new_uri(self.world, uri)
+        if not c_node:
+            raise ValueError("Invalid URI '%s'" % uri)
+
+        return Node.wrap(self, c_node)
 
     def new_file_uri(self, host, path):
         """Create a new file URI node.  The host may be None."""
diff --git a/bindings/test/python/test_api.py b/bindings/test/python/test_api.py
index c3e0752..59fc201 100644
--- a/bindings/test/python/test_api.py
+++ b/bindings/test/python/test_api.py
@@ -63,8 +63,8 @@ class UriTests(unittest.TestCase):
         self.world.load_all()
 
     def testInvalidURI(self):
-        self.plugin_uri = self.world.new_uri("invalid_uri")
-        self.assertIsNone(self.plugin_uri)
+        with self.assertRaises(ValueError):
+            self.plugin_uri = self.world.new_uri("invalid_uri")
 
     def testNonExistentURI(self):
         self.plugin_uri = self.world.new_uri("exist:does_not")
@@ -116,6 +116,8 @@ class PluginClassesTests(unittest.TestCase):
         self.assertGreater(len(classes), 1)
         self.assertIsNotNone(classes[0])
         self.assertIsNotNone(classes[pclass.get_uri()])
+        with self.assertRaises(KeyError):
+            classes["http://example.org/notaclass"].get_uri()
 
 
 class LoadTests(unittest.TestCase):
@@ -151,6 +153,9 @@ class PluginTests(unittest.TestCase):
         self.assertTrue(self.plugin in self.plugins)
         self.assertTrue(self.plugin.get_uri() in self.plugins)
         self.assertEqual(self.plugins[self.plugin.get_uri()], self.plugin)
+        with self.assertRaises(KeyError):
+            self.plugins["http://example.org/notaplugin"].get_uri()
+
         self.assertIsNotNone(
             self.plugin,
             msg="Test plugin not found at location: '" + location + "'",
@@ -386,6 +391,9 @@ class UITests(unittest.TestCase):
         )
         self.assertEqual(1, len(uis))
         self.assertEqual(str(uis[0]), str(ui_uri))
+        with self.assertRaises(KeyError):
+            uis["http://example.org/notaui"].get_uri()
+
         self.assertEqual(uis[0], str(ui_uri))
         self.assertEqual(uis[0].get_uri(), ui_uri)
         self.assertEqual(uis[0].get_bundle_uri(), self.bundle_uri)