1 files changed, 81 insertions, 0 deletions
diff --git a/obnamlib/structurederror_finder.py b/obnamlib/structurederror_finder.py
new file mode 100644
index 00000000..1de04c65
--- /dev/null
+++ b/obnamlib/structurederror_finder.py
@@ -0,0 +1,81 @@
+#!/usr/bin/env python
+# Copyright 2014-2015  Lars Wirzenius
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# =*= License: GPL-3+ =*=
+
+
+# This module contains a fair bit of Python magic. Tread carefully.
+# Like all the worst magic, it has no automated tests, either. Treat
+# this module as if it were a sleeping dragon. Do not meddle in the
+# affairs of dragons, for they are cranky and you are good with
+# ketchup.
+
+
+import imp
+import inspect
+import os
+
+
+import obnamlib
+
+
+def find_structured_errors(top_module, plugin_manager):
+    modules = _find_modules(top_module)
+    modules += _find_plugin_modules(plugin_manager)
+    return _find_errors(modules)
+
+
+def _find_modules(top_module):
+    result = set()
+    queue = [top_module]
+    while queue:
+        module = queue.pop()
+        if module not in result:
+            result.add(module)
+            queue.extend(_get_submodules(module))
+    return list(result)
+
+
+def _get_submodules(module):
+    objs = [getattr(module, name) for name in dir(module)]
+    return [x for x in objs if inspect.ismodule(x)]
+
+
+def _find_plugin_modules(plugin_manager):
+    modules = []
+    for filename in plugin_manager.plugin_files:
+        module_name, ext = os.path.splitext(os.path.basename(filename))
+        with open(filename, 'rb') as f:
+            module = imp.load_module(
+                module_name, f, filename, ('.py', 'r', imp.PY_SOURCE))
+        modules.append(module)
+    return modules
+
+
+def _find_errors(modules):
+    result = set()
+    for module in modules:
+        for name in dir(module):
+            obj = getattr(module, name)
+            if _is_structured_error(obj):
+                result.add(obj)
+    return list(result)
+
+
+def _is_structured_error(obj):
+    return (type(obj) is type and
+            issubclass(obj, obnamlib.StructuredError) and
+            hasattr(obj, 'msg'))