Progress on plugins

1 files changed, 120 insertions, 7 deletions

diff --git a/tests/test_plugins.py b/tests/test_plugins.py
index 154f1a7d..d60ce77b 100644
--- a/tests/test_plugins.py
+++ b/tests/test_plugins.py
@@ -1,7 +1,11 @@
 """Tests for plugins."""
 
+import os.path
+
 import coverage
-from coverage.plugin import load_plugins
+from coverage.codeunit import CodeUnit
+from coverage.parser import CodeParser
+from coverage.plugin import Plugins, overrides
 
 from tests.coveragetest import CoverageTest
 
@@ -24,7 +28,7 @@ class FakeConfig(object):
 
 
 class PluginUnitTest(CoverageTest):
-    """Test load_plugins directly."""
+    """Test Plugins.load_plugins directly."""
 
     def test_importing_and_configuring(self):
         self.make_file("plugin1.py", """\
@@ -37,7 +41,7 @@ class PluginUnitTest(CoverageTest):
             """)
 
         config = FakeConfig("plugin1", {'a':'hello'})
-        plugins = load_plugins(["plugin1"], config)
+        plugins = list(Plugins.load_plugins(["plugin1"], config))
 
         self.assertEqual(len(plugins), 1)
         self.assertEqual(plugins[0].this_is, "me")
@@ -61,7 +65,7 @@ class PluginUnitTest(CoverageTest):
             """)
 
         config = FakeConfig("plugin1", {'a':'hello'})
-        plugins = load_plugins(["plugin1", "plugin2"], config)
+        plugins = list(Plugins.load_plugins(["plugin1", "plugin2"], config))
 
         self.assertEqual(len(plugins), 2)
         self.assertEqual(plugins[0].this_is, "me")
@@ -71,7 +75,7 @@ class PluginUnitTest(CoverageTest):
 
     def test_cant_import(self):
         with self.assertRaises(ImportError):
-            _ = load_plugins(["plugin_not_there"], None)
+            _ = Plugins.load_plugins(["plugin_not_there"], None)
 
     def test_ok_to_not_define_plugin(self):
         self.make_file("plugin2.py", """\
@@ -79,7 +83,7 @@ class PluginUnitTest(CoverageTest):
 
             Nothing = 0
             """)
-        plugins = load_plugins(["plugin2"], None)
+        plugins = list(Plugins.load_plugins(["plugin2"], None))
         self.assertEqual(plugins, [])
 
 
@@ -87,6 +91,7 @@ class PluginTest(CoverageTest):
     """Test plugins through the Coverage class."""
 
     def test_plugin_imported(self):
+        # Prove that a plugin will be imported.
         self.make_file("my_plugin.py", """\
             with open("evidence.out", "w") as f:
                 f.write("we are here!")
@@ -98,7 +103,115 @@ class PluginTest(CoverageTest):
         with open("evidence.out") as f:
             self.assertEqual(f.read(), "we are here!")
 
-    def test_bad_plugin_raises_import_error(self):
+    def test_missing_plugin_raises_import_error(self):
+        # Prove that a missing plugin will raise an ImportError.
         with self.assertRaises(ImportError):
             cov = coverage.Coverage(plugins=["foo"])
             cov.start()
+
+    def test_bad_plugin_isnt_hidden(self):
+        # Prove that a plugin with an error in it will raise the error.
+        self.make_file("plugin_over_zero.py", """\
+            1/0
+            """)
+        with self.assertRaises(ZeroDivisionError):
+            _ = coverage.Coverage(plugins=["plugin_over_zero"])
+
+    def test_importing_myself(self):
+        self.make_file("simple.py", """\
+            import try_xyz
+            a = 1
+            b = 2
+            """)
+        self.make_file("try_xyz.py", """\
+            c = 3
+            d = 4
+            """)
+
+        cov = coverage.Coverage(plugins=["tests.test_plugins"])
+
+        # Import the python file, executing it.
+        self.start_import_stop(cov, "simple")
+
+        _, statements, missing, _ = cov.analysis("simple.py")
+        self.assertEqual(statements, [1,2,3])
+        self.assertEqual(missing, [])
+        _, statements, _, _ = cov.analysis("/src/try_ABC.zz")
+        self.assertEqual(statements, [105, 106, 107, 205, 206, 207])
+
+
+class Plugin(coverage.CoveragePlugin):
+    def trace_judge(self, disp):
+        if "xyz.py" in disp.original_filename:
+            disp.trace = True
+            disp.source_filename = os.path.join(
+                "/src",
+                os.path.basename(
+                    disp.original_filename.replace("xyz.py", "ABC.zz")
+                )
+            )
+
+    def line_number_range(self, frame):
+        lineno = frame.f_lineno
+        return lineno*100+5, lineno*100+7
+
+    def code_unit_class(self, filename):
+        return PluginCodeUnit
+
+class PluginCodeUnit(CodeUnit):
+    def get_parser(self, exclude=None):
+        return PluginParser()
+
+class PluginParser(CodeParser):
+    def parse_source(self):
+        return set([105, 106, 107, 205, 206, 207]), set([])
+
+
+class OverridesTest(CoverageTest):
+    """Test plugins.py:overrides."""
+
+    run_in_temp_dir = False
+
+    def test_overrides(self):
+        class SomeBase(object):
+            """Base class, two base methods."""
+            def method1(self):
+                pass
+
+            def method2(self):
+                pass
+
+        class Derived1(SomeBase):
+            """Simple single inheritance."""
+            def method1(self):
+                pass
+
+        self.assertTrue(overrides(Derived1(), "method1", SomeBase))
+        self.assertFalse(overrides(Derived1(), "method2", SomeBase))
+
+        class FurtherDerived1(Derived1):
+            """Derive again from Derived1, inherit its method1."""
+            pass
+
+        self.assertTrue(overrides(FurtherDerived1(), "method1", SomeBase))
+        self.assertFalse(overrides(FurtherDerived1(), "method2", SomeBase))
+
+        class FurtherDerived2(Derived1):
+            """Override the overridden method."""
+            def method1(self):
+                pass
+
+        self.assertTrue(overrides(FurtherDerived2(), "method1", SomeBase))
+        self.assertFalse(overrides(FurtherDerived2(), "method2", SomeBase))
+
+        class Mixin(object):
+            """A mixin that overrides method1."""
+            def method1(self):
+                pass
+
+        class Derived2(Mixin, SomeBase):
+            """A class that gets the method from the mixin."""
+            pass
+
+        self.assertTrue(overrides(Derived2(), "method1", SomeBase))
+        self.assertFalse(overrides(Derived2(), "method2", SomeBase))