Add Extension class

6 files changed, 43 insertions, 38 deletions

diff --git a/sphinx/application.py b/sphinx/application.py
index 92176487e..7b6b0788e 100644
--- a/sphinx/application.py
+++ b/sphinx/application.py
@@ -58,6 +58,7 @@ if False:
     from sphinx.builders import Builder  # NOQA
     from sphinx.domains import Domain, Index  # NOQA
     from sphinx.environment.collectors import EnvironmentCollector  # NOQA
+    from sphinx.extensions import Extension  # NOQA
 
 builtin_extensions = (
     'sphinx.builders.applehelp',
@@ -112,8 +113,7 @@ class Sphinx(object):
                  parallel=0):
         # type: (unicode, unicode, unicode, unicode, unicode, Dict, IO, IO, bool, bool, List[unicode], int, int) -> None  # NOQA
         self.verbosity = verbosity
-        self._extensions = {}                   # type: Dict[unicode, Any]
-        self._extension_metadata = {}           # type: Dict[unicode, Dict[unicode, Any]]
+        self.extensions = {}                    # type: Dict[unicode, Extension]
         self._additional_source_parsers = {}    # type: Dict[unicode, Parser]
         self._setting_up_extension = ['?']      # type: List[unicode]
         self.domains = {}                       # type: Dict[unicode, Type[Domain]]
diff --git a/sphinx/builders/__init__.py b/sphinx/builders/__init__.py
index f7593020a..adb3a3b8a 100644
--- a/sphinx/builders/__init__.py
+++ b/sphinx/builders/__init__.py
@@ -17,6 +17,7 @@ try:
 except ImportError:
     multiprocessing = None
 
+from six import itervalues
 from docutils import nodes
 
 from sphinx.util import i18n, path_stabilize, logging, status_iterator
@@ -337,11 +338,10 @@ class Builder(object):
         self.parallel_ok = False
         if parallel_available and self.app.parallel > 1 and self.allow_parallel:
             self.parallel_ok = True
-            for extname, md in self.app._extension_metadata.items():
-                par_ok = md.get('parallel_write_safe', True)
-                if not par_ok:
+            for extension in itervalues(self.app.extensions):
+                if not extension.parallel_write_safe:
                     logger.warning('the %s extension is not safe for parallel '
-                                   'writing, doing serial write', extname)
+                                   'writing, doing serial write', extension.name)
                     self.parallel_ok = False
                     break
 
diff --git a/sphinx/environment/__init__.py b/sphinx/environment/__init__.py
index 014850f7f..45dfae8f5 100644
--- a/sphinx/environment/__init__.py
+++ b/sphinx/environment/__init__.py
@@ -43,6 +43,7 @@ from sphinx.util.matching import compile_matchers
 from sphinx.util.parallel import ParallelTasks, parallel_available, make_chunks
 from sphinx.util.websupport import is_commentable
 from sphinx.errors import SphinxError, ExtensionError
+from sphinx.locale import _
 from sphinx.transforms import SphinxTransformer
 from sphinx.versioning import add_uids, merge_doctrees
 from sphinx.deprecation import RemovedInSphinx17Warning, RemovedInSphinx20Warning
@@ -559,22 +560,20 @@ class BuildEnvironment(object):
         # check if we should do parallel or serial read
         par_ok = False
         if parallel_available and len(docnames) > 5 and self.app.parallel > 1:
-            par_ok = True
-            for extname, md in self.app._extension_metadata.items():
-                ext_ok = md.get('parallel_read_safe')
-                if ext_ok:
-                    continue
-                if ext_ok is None:
-                    logger.warning('the %s extension does not declare if it '
-                                   'is safe for parallel reading, assuming it '
-                                   'isn\'t - please ask the extension author to '
-                                   'check and make it explicit', extname)
+            for ext in itervalues(self.app.extensions):
+                if ext.parallel_read_safe is None:
+                    logger.warning(_('the %s extension does not declare if it is safe '
+                                     'for parallel reading, assuming it isn\'t - please '
+                                     'ask the extension author to check and make it '
+                                     'explicit'), ext.name)
                     logger.warning('doing serial read')
-                else:
-                    logger.warning('the %s extension is not safe for parallel '
-                                   'reading, doing serial read', extname)
-                par_ok = False
-                break
+                    break
+                elif ext.parallel_read_safe is False:
+                    break
+            else:
+                # all extensions support parallel-read
+                par_ok = True
+
         if par_ok:
             self._read_parallel(docnames, self.app, nproc=self.app.parallel)
         else:
diff --git a/sphinx/environment/adapters/indexentries.py b/sphinx/environment/adapters/indexentries.py
index 31ec58301..4eb1f8a32 100644
--- a/sphinx/environment/adapters/indexentries.py
+++ b/sphinx/environment/adapters/indexentries.py
@@ -13,10 +13,10 @@ import bisect
 import unicodedata
 from itertools import groupby
 
-from six import text_type
+from six import text_type, iteritems
 
 from sphinx.locale import _
-from sphinx.util import iteritems, split_into, logging
+from sphinx.util import split_into, logging
 
 if False:
     # For type annotation
diff --git a/sphinx/extensions.py b/sphinx/extensions.py
index d51b6760d..8e929a48b 100644
--- a/sphinx/extensions.py
+++ b/sphinx/extensions.py
@@ -33,11 +33,20 @@ EXTENSION_BLACKLIST = {
 }  # type: Dict[unicode, unicode]
 
 
+class Extension(object):
+    def __init__(self, name, module, **kwargs):
+        self.name = name
+        self.module = module
+        self.version = kwargs.pop('version', 'unknown version')
+        self.parallel_read_safe = kwargs.pop('parallel_read_safe', None)
+        self.parallel_write_safe = kwargs.pop('parallel_read_safe', True)
+        self.metadata = kwargs
+
+
 def load(app, extname):
     # type: (Sphinx, unicode) -> None
     """Load a Sphinx extension."""
-    if extname in app._extensions:
-        # alread loaded
+    if extname in app.extensions:  # alread loaded
         return
     if extname in EXTENSION_BLACKLIST:
         logger.warning(_('the extension %r was already merged with Sphinx since '
@@ -78,9 +87,7 @@ def load(app, extname):
                          'its setup() function; it should return None or a '
                          'metadata dictionary'), extname)
 
-    metadata.setdefault('version', 'unknown version')
-    app._extensions[extname] = mod
-    app._extension_metadata[extname] = metadata
+    app.extensions[extname] = Extension(extname, mod, **metadata)
     app._setting_up_extension.pop()
 
 
@@ -91,15 +98,15 @@ def confirm(app, requirements):
         return
 
     for extname, reqversion in iteritems(requirements):
-        if extname not in app._extensions:
+        extension = app.extensions.get(extname)
+        if extension is None:
             logger.warning(_('needs_extensions config value specifies a '
                              'version requirement for extension %s, but it is '
                              'not loaded'), extname)
             continue
 
-        extversion = app._extension_metadata[extname].get('version')
-        if extversion == 'unknown version' or reqversion > extversion:
+        if extension.version == 'unknown version' or reqversion > extension.version:
             raise VersionRequirementError(_('This project needs the extension %s at least in '
                                             'version %s and therefore cannot be built with '
                                             'the loaded version (%s).') %
-                                          (extname, reqversion, extversion))
+                                          (extname, reqversion, extension.version))
diff --git a/sphinx/util/__init__.py b/sphinx/util/__init__.py
index a3823546d..adf526e06 100644
--- a/sphinx/util/__init__.py
+++ b/sphinx/util/__init__.py
@@ -22,7 +22,7 @@ from os import path
 from codecs import BOM_UTF8
 from collections import deque
 
-from six import iteritems, text_type, binary_type
+from six import text_type, binary_type
 from six.moves import range
 from six.moves.urllib.parse import urlsplit, urlunsplit, quote_plus, parse_qsl, urlencode
 from docutils.utils import relative_path
@@ -227,14 +227,13 @@ def save_traceback(app):
                    jinja2.__version__,  # type: ignore
                    last_msgs)).encode('utf-8'))
     if app is not None:
-        for extname, extmod in iteritems(app._extensions):
-            modfile = getattr(extmod, '__file__', 'unknown')
+        for ext in app.extensions:
+            modfile = getattr(ext.module, '__file__', 'unknown')
             if isinstance(modfile, bytes):
                 modfile = modfile.decode(fs_encoding, 'replace')
-            version = app._extension_metadata[extname]['version']
-            if version != 'builtin':
+            if ext.version != 'builtin':
                 os.write(fd, ('#   %s (%s) from %s\n' %
-                              (extname, version, modfile)).encode('utf-8'))
+                              (ext.name, ext.version, modfile)).encode('utf-8'))
     os.write(fd, exc_format.encode('utf-8'))
     os.close(fd)
     return path