add @require_module('module') that skip a test if the module can not be imported

2 files changed, 52 insertions, 8 deletions

diff --git a/decorators.py b/decorators.py
index 7ed4554..71cd325 100644
--- a/decorators.py
+++ b/decorators.py
@@ -167,3 +167,18 @@ def require_version(version):
             return f
     return check_require_version
 
+def require_module(module):
+    """ Check if the given module is loaded. Skip the test if not.
+    """
+    def check_require_module(f):
+        try:
+            __import__(module)
+            #print module, 'imported'
+            return f
+        except ImportError:
+            #print module, 'can not be imported'
+            def new_f(self, *args, **kwargs):
+                self.skip('%s can not be imported.' % module)
+            new_f.__name__ = f.__name__
+            return new_f
+    return check_require_module
diff --git a/test/unittest_decorators.py b/test/unittest_decorators.py
index 4a8b588..855f242 100644
--- a/test/unittest_decorators.py
+++ b/test/unittest_decorators.py
@@ -1,6 +1,6 @@
 import sys
-from logilab.common.testlib import TestCase, unittest_main
-from logilab.common.decorators import require_version
+from logilab.common.testlib import TestCase, unittest_main, TestSuite
+from logilab.common.decorators import require_version, require_module
 
 class DecoratorsTC(TestCase):
     def test_require_version_good(self):
@@ -13,9 +13,9 @@ class DecoratorsTC(TestCase):
         compare = ('2.4', '2.5', '2.5.4', '2.5.5')
         for version in compare: 
             decorator = require_version(version)
-            self.assertEquals(func, decorator(func), '%s =< %s : function return by \
-                  the decorator should be the same.' % (version, 
-                  '.'.join([str(element) for element in current])))
+            self.assertEquals(func, decorator(func), '%s =< %s : function \
+                return by the decorator should be the same.' % (version, 
+                '.'.join([str(element) for element in current])))
 
     def test_require_version_bad(self):
         """ should return a different function : skipping test
@@ -27,9 +27,9 @@ class DecoratorsTC(TestCase):
         compare = ('2.5.6', '2.6', '2.6.5')
         for version in compare: 
             decorator = require_version(version)
-            self.assertNotEquals(func, decorator(func), '%s >= %s : function return by  \
-                  the decorator should NOT be the same.' % ('.'.join([str(element) for
-                  element in current]), version))
+            self.assertNotEquals(func, decorator(func), '%s >= %s : function \
+                 return by the decorator should NOT be the same.' 
+                 % ('.'.join([str(element) for element in current]), version))
 
     def test_require_version_exception(self):
         """ should throw a ValueError exception
@@ -41,5 +41,34 @@ class DecoratorsTC(TestCase):
             decorator = require_version(version)
             self.assertRaises(ValueError, decorator, func)
 
+    def test_require_module_good(self):
+        """ should return the same function
+        """
+        def func() :
+            pass
+        module = 'sys'
+        decorator = require_module(module)
+        self.assertEquals(func, decorator(func), 'module %s exists : function \
+            return by the decorator should be the same.' % module)
+
+    def test_require_module_bad(self):
+        """ should return a different function : skipping test
+        """
+        def func() :
+            pass
+        modules = ('bla', 'blo', 'bli')
+        for module in modules:
+            try:
+                __import__(module)
+                pass
+            except ImportError:
+                decorator = require_module(module)
+                self.assertNotEquals(func, decorator(func), 'module %s does \
+                    not exist : function return by the decorator should \
+                    NOT be the same.' % module)
+                return
+        print 'all modules in %s exist. Could not test %s' % (', '.join(modules), 
+            sys._getframe().f_code.co_name)
+
 if __name__ == '__main__':
     unittest_main()