Avoid overwriting settings by storing them separately on the configuration context

.travis.yml

@@ -1,43 +1,46 @@
 language: python
-python:
-  - 2.6
+python: 2.7
+sudo: false
 install: 
-  # Supposed to help get PIL to install on PyPi
-  # https://github.com/python-imaging/Pillow/issues/570
-  - sudo apt-get install python-tk
-
-  # To install external filter binaries, we first need to install
-  # RubyGems and Node/NPM. I'm not sure why, since it seems clear
-  # that NVM and RVM are pre-installed (see below).
-  - sudo apt-get install python-software-properties
-  - sudo apt-add-repository -y ppa:chris-lea/node.js
-  - sudo apt-get update
-  - sudo apt-get install nodejs rubygems
-  - sudo apt-get install npm
-  - npm install -g postcss autoprefixer
+  # Setup a virtualenv (to allow installing nodeenv)
+  - rm -rf py_env
+  - virtualenv py_env
+  - . py_env/bin/activate
+  - pip install nodeenv
 
-  # These are useful for debugging this mess.
-  #- env
-  #- gem env
-  #- rvm info
+  # Install and activate nodeenv (to get a current version of nodejs)
+  - rm -rf node_env
+  - source py_env/bin/activate 
+  - nodeenv node_env --node=4.0.0 --prebuilt
+  - source node_env/bin/activate
 
-  # Use non-http registry? https://github.com/n1k0/casperjs/issues/876
-  # Without this, installing doesn't work.  
-  - sudo npm config set registry http://registry.npmjs.org/
-
-  # Now install the external filter binaries, finally. 
-  # If we use sudo for this, ruby gems will not work: it seems they are
-  # then installed globally, but are then searched for in a RVM location.
-  # (Clearing GEM_HOME might be a way to fix this, if sudo where necessary).
+  # Install node requirements (inside the nodeenv)
   - sh requirements-dev.sh
 
-  # Install our test runner
+  # Install our test runner (inside the virtualenv)
   - pip install tox
 
-script: tox
-notifications:
-  email:
-    - [email protected]
+env: 
+  - TOX_ENV=py27
+  - TOX_ENV=py33 
+  - TOX_ENV=py34
+  - TOX_ENV=py35
+  - TOX_ENV=pypy
+  - TOX_ENV=no-glob2
+  - TOX_ENV=external-jsmin
+script: tox -e $TOX_ENV
 branches:
   only:
     - master
+addons:
+  apt:
+    sources:
+      - deadsnakes
+    packages:
+      - python3.3
+      - python3.4
+      - python3.5
+      - python-tk
+      - python-software-properties
+      - rubygems
+      - python-virtualenv

requirements-dev-2.x.pip

@@ -7,4 +7,4 @@ slimmer
 cssmin
 
 # Default rsmin package is not installable via pip
-http://michael.elsdoerfer.name/rjsmin/rjsmin-1.0.1-webassets.tar.gz
+rjsmin

requirements-dev.pip

@@ -13,7 +13,6 @@ mock
 Sphinx
 
 # Libs that are needed for some features
-PyYaml
 glob2
 
 # Libs that are needed by filters.
@@ -22,8 +21,4 @@ cssutils
 yuicompressor
 closure
 slimit==0.8.1
-ply==3.4 # https://github.com/rspivak/slimit/issues/76
-libsass==0.8.3
-
-# Python libs that requiring manual installation
-#cssprefixer
+ply==3.4 # https://github.com/rspivak/slimit/issues/76

requirements-dev.sh

@@ -18,3 +18,5 @@ npm install -g stylus
 npm install -g handlebars
 npm install -g typescript
 npm install -g [email protected]
+npm install -g autoprefixer
+npm install -g postcss-cli

src/webassets/env.py

@@ -435,10 +435,17 @@ def _get_debug(self):
     def _set_cache(self, enable):
         self._storage['cache'] = enable
     def _get_cache(self):
-        cache = get_cache(self._storage['cache'], self)
-        if cache != self._storage['cache']:
-            self._storage['cache'] = cache
-        return cache
+        """ Instantiate the cache once and store it on the context.
+            If the underlying setting changes, reinstantiate the cache.
+        """
+        if hasattr(self, '_cache'):
+            stored_setting, stored_cache = self._cache
+            if stored_setting == self._storage['cache']:
+                return stored_cache
+
+        new_cache = get_cache(self._storage['cache'], self)
+        self._cache = (self._storage['cache'], new_cache)
+        return new_cache
     cache = property(_get_cache, _set_cache, doc=
     """Controls the behavior of the cache. The cache will speed up rebuilding
     of your bundles, by caching individual filter results. This can be
@@ -480,10 +487,24 @@ def _get_auto_build(self):
     def _set_manifest(self, manifest):
         self._storage['manifest'] = manifest
     def _get_manifest(self):
-        manifest = get_manifest(self._storage['manifest'], env=self)
-        if manifest != self._storage['manifest']:
-            self._storage['manifest'] = manifest
-        return manifest
+        """ Instantiate the manifest once and store it on the context.
+            If the underlying setting changes, reinstantiate the manifest.
+        """
+        if hasattr(self, '_manifest'):
+            stored_setting, stored_manifest = self._manifest
+            if stored_setting == self._storage['manifest']:
+                return stored_manifest
+
+        try:
+            new_manifest = get_manifest(self._storage['manifest'], env=self)
+        except ValueError:
+            new_manifest = get_manifest(
+                # abspath() is important, or this will be considered
+                # relative to Environment.directory.
+                "file:%s" % os.path.abspath(self._storage['manifest']),
+                env=self)
+        self._manifest = (self._storage['manifest'], new_manifest)
+        return new_manifest
     manifest = property(_get_manifest, _set_manifest, doc=
     """A manifest persists information about the versions bundles
     are at.
@@ -530,10 +551,17 @@ def _get_manifest(self):
     def _set_versions(self, versions):
         self._storage['versions'] = versions
     def _get_versions(self):
-        versions = get_versioner(self._storage['versions'])
-        if versions != self._storage['versions']:
-            self._storage['versions'] = versions
-        return versions
+        """ Instantiate the versioner once and store it on the context.
+            If the underlying setting changes, reinstantiate the versioner.
+        """
+        if hasattr(self, '_versions'):
+            stored_setting, stored_versions = self._versions
+            if stored_setting == self._storage['versions']:
+                return stored_versions
+
+        new_versions = get_versioner(self._storage['versions'])
+        self._versions = (self._storage['versions'], new_versions)
+        return new_versions
     versions = property(_get_versions, _set_versions, doc=
     """Defines what should be used as a Bundle ``version``.
 
@@ -563,10 +591,17 @@ def _get_versions(self):
     def set_updater(self, updater):
         self._storage['updater'] = updater
     def get_updater(self):
-        updater = get_updater(self._storage['updater'])
-        if updater != self._storage['updater']:
-            self._storage['updater'] = updater
-        return updater
+        """ Instantiate the updater once and store it on the context.
+            If the underlying setting changes, reinstantiate the updater.
+        """
+        if hasattr(self, '_updater'):
+            stored_setting, stored_updater = self._updater
+            if stored_setting == self._storage['updater']:
+                return stored_updater
+
+        new_updater = get_updater(self._storage['updater'])
+        self._updater = (self._storage['updater'], new_updater)
+        return new_updater
     updater = property(get_updater, set_updater, doc=
     """Controls how the ``auto_build`` option should determine
     whether a bundle needs to be rebuilt.

src/webassets/script.py

@@ -95,16 +95,7 @@ def __call__(self, bundles=None, output=None, directory=None, no_cache=None,
             # TODO: Reset again (refactor commands to be classes)
             self.environment.debug = False
 
-        # TODO: Oh how nice it would be to use the future options stack.
         if manifest is not None:
-            try:
-                manifest = get_manifest(manifest, env=self.environment)
-            except ValueError:
-                manifest = get_manifest(
-                    # abspath() is important, or this will be considered
-                    # relative to Environment.directory.
-                    "file:%s" % os.path.abspath(manifest),
-                    env=self.environment)
             self.environment.manifest = manifest
 
         # Use output as a dict.

tox.ini

@@ -18,6 +18,10 @@ deps26 =
 deps3 =
     -r{toxinidir}/requirements-dev.pip
 
+[testenv:py35]
+basepython = python3.5
+deps =
+    {[base]deps3}
 
 [testenv:py33]
 basepython = python3.3
@@ -68,11 +72,3 @@ deps =
     pytest==2.5.2
     mock==0.8.0
     jsmin==2.0.2
-
-[testenv:external-rjsmin]
-basepython = python2.7
-deps =
-    nose==1.0.0
-    pytest==2.5.2
-    mock==0.8.0
-    http://michael.elsdoerfer.name/rjsmin/rjsmin-1.0.1-webassets.tar.gz