More-serious plugin support

4 files changed, 75 insertions, 22 deletions

diff --git a/coverage/config.py b/coverage/config.py
index 1826e5c2..c671ef75 100644
--- a/coverage/config.py
+++ b/coverage/config.py
@@ -37,6 +37,13 @@ class HandyConfigParser(configparser.RawConfigParser):
         section = self.section_prefix + section
         return configparser.RawConfigParser.options(self, section)
 
+    def get_section(self, section):
+        """Get the contents of a section, as a dictionary."""
+        d = {}
+        for opt in self.options(section):
+            d[opt] = self.get(section, opt)
+        return d
+
     def get(self, section, *args, **kwargs):
         """Get a value, replacing environment variables also.
 
@@ -163,6 +170,9 @@ class CoverageConfig(object):
         # Defaults for [paths]
         self.paths = {}
 
+        # Options for plugins
+        self.plugin_options = {}
+
     def from_environment(self, env_var):
         """Read configuration from the `env_var` environment variable."""
         # Timidity: for nose users, read an environment variable.  This is a
@@ -200,17 +210,22 @@ class CoverageConfig(object):
         self.config_files.extend(files_read)
 
         for option_spec in self.CONFIG_FILE_OPTIONS:
-            self.set_attr_from_config_option(cp, *option_spec)
+            self._set_attr_from_config_option(cp, *option_spec)
 
         # [paths] is special
         if cp.has_section('paths'):
             for option in cp.options('paths'):
                 self.paths[option] = cp.getlist('paths', option)
 
+        # plugins can have options
+        for plugin in self.plugins:
+            if cp.has_section(plugin):
+                self.plugin_options[plugin] = cp.get_section(plugin)
+
         return True
 
     CONFIG_FILE_OPTIONS = [
-        # These are *args for set_attr_from_config_option:
+        # These are *args for _set_attr_from_config_option:
         #   (attr, where, type_="")
         #
         #   attr is the attribute to set on the CoverageConfig object.
@@ -250,9 +265,13 @@ class CoverageConfig(object):
         ('xml_output', 'xml:output'),
         ]
 
-    def set_attr_from_config_option(self, cp, attr, where, type_=''):
+    def _set_attr_from_config_option(self, cp, attr, where, type_=''):
         """Set an attribute on self if it exists in the ConfigParser."""
         section, option = where.split(":")
         if cp.has_option(section, option):
             method = getattr(cp, 'get'+type_)
             setattr(self, attr, method(section, option))
+
+    def get_plugin_options(self, plugin):
+        """Get a dictionary of options for the plugin named `plugin`."""
+        return self.plugin_options.get(plugin, {})
diff --git a/coverage/control.py b/coverage/control.py
index deb4e00f..6d232e5b 100644
--- a/coverage/control.py
+++ b/coverage/control.py
@@ -135,8 +135,8 @@ class Coverage(object):
         self.debug = DebugControl(self.config.debug, debug_file or sys.stderr)
 
         # Load plugins
-        tracer_classes = load_plugins(self.config.plugins, "tracer")
-        self.tracer_plugins = [cls() for cls in tracer_classes]
+        plugins = load_plugins(self.config.plugins, self.config)
+        self.tracer_plugins = []#[cls() for cls in tracer_classes]
 
         self.auto_data = auto_data
 
@@ -282,10 +282,10 @@ class Coverage(object):
 
         # Try the plugins, see if they have an opinion about the file.
         for tracer in self.tracer_plugins:
-            ext_disp = tracer.should_trace(canonical)
-            if ext_disp:
-                ext_disp.extension = tracer
-                return ext_disp
+            plugin_disp = tracer.should_trace(canonical)
+            if plugin_disp:
+                plugin_disp.plugin = tracer
+                return plugin_disp
 
         # If the user specified source or include, then that's authoritative
         # about the outer bound of what to measure and we don't have to apply
diff --git a/coverage/plugin.py b/coverage/plugin.py
index 0b557106..8e26ae6b 100644
--- a/coverage/plugin.py
+++ b/coverage/plugin.py
@@ -1,20 +1,30 @@
 """Plugin management for coverage.py"""
 
-def load_plugins(modules, name):
-    """Load plugins from `modules`, finding them by `name`.
+import sys
 
-    Yields the loaded plugins.
+
+class CoveragePlugin(object):
+    """Base class for coverage.py plugins."""
+    def __init__(self, options):
+        self.options = options
+
+
+def load_plugins(modules, config):
+    """Load plugins from `modules`.
+
+    Returns a list of loaded and configured plugins.
 
     """
+    plugins = []
 
     for module in modules:
-        try:
-            __import__(module)
-            mod = sys.modules[module]
-        except ImportError:
-            blah()
-            continue
-
-        entry = getattr(mod, name, None)
-        if entry:
-            yield entry
+        __import__(module)
+        mod = sys.modules[module]
+
+        plugin_class = getattr(mod, "Plugin", None)
+        if plugin_class:
+            options = config.get_plugin_options(module)
+            plugin = plugin_class(options)
+            plugins.append(plugin)
+
+    return plugins
diff --git a/tests/test_config.py b/tests/test_config.py
index 7409f4aa..bf84423d 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -1,6 +1,8 @@
 # -*- coding: utf-8 -*-
 """Test the config file handling for coverage.py"""
 
+import sys, os
+
 import coverage
 from coverage.misc import CoverageException
 
@@ -125,6 +127,12 @@ class ConfigTest(CoverageTest):
 class ConfigFileTest(CoverageTest):
     """Tests of the config file settings in particular."""
 
+    def setUp(self):
+        super(ConfigFileTest, self).setUp()
+        # Parent class saves and restores sys.path, we can just modify it.
+        # Add modules to the path so we can import plugins.
+        sys.path.append(self.nice_file(os.path.dirname(__file__), 'modules'))
+
     # This sample file tries to use lots of variation of syntax...
     # The {section} placeholder lets us nest these settings in another file.
     LOTSA_SETTINGS = """\
@@ -136,6 +144,9 @@ class ConfigFileTest(CoverageTest):
         cover_pylib = TRUE
         parallel = on
         include = a/   ,    b/
+        plugins =
+            plugins.a_plugin
+            plugins.another
 
         [{section}report]
         ; these settings affect reporting.
@@ -174,6 +185,10 @@ class ConfigFileTest(CoverageTest):
 
         other = other, /home/ned/other, c:\\Ned\\etc
 
+        [{section}plugins.a_plugin]
+        hello = world
+        ; comments still work.
+        names = Jane/John/Jenny
         """
 
     # Just some sample setup.cfg text from the docs.
@@ -212,6 +227,9 @@ class ConfigFileTest(CoverageTest):
         self.assertEqual(cov.config.partial_always_list,
             ["if 0:", "while True:"]
             )
+        self.assertEqual(cov.config.plugins,
+            ["plugins.a_plugin", "plugins.another"]
+            )
         self.assertTrue(cov.config.show_missing)
         self.assertEqual(cov.config.html_dir, r"c:\tricky\dir.somewhere")
         self.assertEqual(cov.config.extra_css, "something/extra.css")
@@ -224,6 +242,12 @@ class ConfigFileTest(CoverageTest):
             'other': ['other', '/home/ned/other', 'c:\\Ned\\etc']
             })
 
+        self.assertEqual(cov.config.get_plugin_options("plugins.a_plugin"), {
+            'hello': 'world',
+            'names': 'Jane/John/Jenny',
+            })
+        self.assertEqual(cov.config.get_plugin_options("plugins.another"), {})
+
     def test_config_file_settings(self):
         self.make_file(".coveragerc", self.LOTSA_SETTINGS.format(section=""))
         cov = coverage.coverage()