Instance paths are now moved into virtualenv/share/appname-instance if installed

flask/app.py

@@ -447,6 +447,23 @@ class Flask(_PackageBoundObject):
     error_handlers = property(_get_error_handlers, _set_error_handlers)
     del _get_error_handlers, _set_error_handlers
 
+    @locked_cached_property
+    def name(self):
+        """The name of the application.  This is usually the import name
+        with the difference that it's guessed from the run file if the
+        import name is main.  This name is used as a display name when
+        Flask needs the name of the application.  It can be set and overriden
+        to change the value.
+
+        .. versionadded:: 0.8
+        """
+        if self.import_name == '__main__':
+            fn = getattr(sys.modules['__main__'], '__file__', None)
+            if fn is None:
+                return 'unknown'
+            return os.path.splitext(os.path.basename(fn))[0]
+        return self.import_name
+
     @property
     def propagate_exceptions(self):
         """Returns the value of the `PROPAGATE_EXCEPTIONS` configuration
@@ -545,14 +562,26 @@ class Flask(_PackageBoundObject):
         .. versionadded:: 0.8
         """
         root_mod = sys.modules[self.import_name.split('.')[0]]
-        instance_path = None
+        # we're not using root_mod.__file__ here since the module could be
+        # virtual.  We're trusting the _PackageBoundObject to have calculated
+        # the proper name.
+        package_path = self.root_path
         if hasattr(root_mod, '__path__'):
-            package_dir = os.path.dirname(root_mod.__file__)
-            instance_path = os.path.join(package_dir, os.path.pardir)
+            package_path = os.path.dirname(package_path)
+        site_parent, site_folder = os.path.split(package_path)
+
+        py_prefix = os.path.abspath(sys.prefix)
+        if package_path.startswith(py_prefix):
+            base_dir = py_prefix
+        elif site_folder == 'site-packages':
+            parent, folder = os.path.split(site_parent)
+            if folder.lower() == 'lib':
+                base_dir = parent
+            else:
+                base_dir = site_parent
         else:
-            instance_path = os.path.dirname(root_mod.__file__)
-        basedir = os.path.normpath(os.path.abspath(instance_path))
-        return os.path.join(basedir, 'instance')
+            return os.path.join(package_path, 'instance')
+        return os.path.join(base_dir, 'share', self.name + '-instance')
 
     def open_instance_resource(self, resource, mode='rb'):
         """Opens a resource from the application's instance folder

flask/helpers.py

@@ -466,7 +466,7 @@ def send_from_directory(directory, filename, **options):
     return send_file(filename, conditional=True, **options)
 
 
-def _get_package_path(name):
+def get_package_path(name):
     """Returns the path to a package or cwd if that cannot be found."""
     try:
         return os.path.abspath(os.path.dirname(sys.modules[name].__file__))
@@ -512,7 +512,7 @@ class _PackageBoundObject(object):
         self.template_folder = template_folder
 
         #: Where is the app root located?
-        self.root_path = _get_package_path(self.import_name)
+        self.root_path = get_package_path(self.import_name)
 
         self._static_folder = None
         self._static_url_path = None

tests/flask_tests.py

@@ -1005,7 +1005,10 @@ class BasicFunctionalityTestCase(unittest.TestCase):
             rv = c.post('/foo', data={}, follow_redirects=True)
             self.assertEqual(rv.data, 'success')
 
-    def test_basic_instance_paths(self):
+
+class InstanceTestCase(unittest.TestCase):
+
+    def test_uninstalled_module_paths(self):
         here = os.path.abspath(os.path.dirname(__file__))
         app = flask.Flask(__name__)
         self.assertEqual(app.instance_path, os.path.join(here, 'instance'))
@@ -1020,9 +1023,60 @@ class BasicFunctionalityTestCase(unittest.TestCase):
         else:
             self.fail('Expected value error')
 
+    def test_uninstalled_package_paths(self):
         from blueprintapp import app
+        here = os.path.abspath(os.path.dirname(__file__))
         self.assertEqual(app.instance_path, os.path.join(here, 'instance'))
 
+    def test_installed_module_paths(self):
+        import types
+        expected_prefix = os.path.abspath('foo')
+        mod = types.ModuleType('myapp')
+        mod.__file__ = os.path.join(expected_prefix, 'lib',
+                                    'site-packages', 'myapp.py')
+        sys.modules['myapp'] = mod
+        try:
+            mod.app = flask.Flask(mod.__name__)
+            self.assertEqual(mod.app.instance_path,
+                             os.path.join(expected_prefix, 'share',
+                                          'myapp-instance'))
+        finally:
+            sys.modules['myapp'] = None
+
+    def test_installed_package_paths(self):
+        import types
+        expected_prefix = os.path.abspath('foo')
+        package_path = os.path.join(expected_prefix, 'lib',
+                                    'site-packages', 'myapp')
+        mod = types.ModuleType('myapp')
+        mod.__path__ = [package_path]
+        mod.__file__ = os.path.join(package_path, '__init__.py')
+        sys.modules['myapp'] = mod
+        try:
+            mod.app = flask.Flask(mod.__name__)
+            self.assertEqual(mod.app.instance_path,
+                             os.path.join(expected_prefix, 'share',
+                                          'myapp-instance'))
+        finally:
+            sys.modules['myapp'] = None
+
+    def test_prefix_installed_paths(self):
+        import types
+        expected_prefix = os.path.abspath(sys.prefix)
+        package_path = os.path.join(expected_prefix, 'lib',
+                                    'site-packages', 'myapp')
+        mod = types.ModuleType('myapp')
+        mod.__path__ = [package_path]
+        mod.__file__ = os.path.join(package_path, '__init__.py')
+        sys.modules['myapp'] = mod
+        try:
+            mod.app = flask.Flask(mod.__name__)
+            self.assertEqual(mod.app.instance_path,
+                             os.path.join(expected_prefix, 'share',
+                                          'myapp-instance'))
+        finally:
+            sys.modules['myapp'] = None
+
 
 class JSONTestCase(unittest.TestCase):
 
@@ -2114,6 +2168,7 @@ def suite():
     suite.addTest(unittest.makeSuite(SubdomainTestCase))
     suite.addTest(unittest.makeSuite(ViewTestCase))
     suite.addTest(unittest.makeSuite(DeprecationsTestCase))
+    suite.addTest(unittest.makeSuite(InstanceTestCase))
     if flask.json_available:
         suite.addTest(unittest.makeSuite(JSONTestCase))
     if flask.signals_available: