Refactored; Initialize imagedir at init() method

sphinx/builders/__init__.py

@@ -44,10 +44,6 @@ class Builder(object):
     versioning_method = 'none'
     # allow parallel write_doc() calls
     allow_parallel = False
-    # basename of images directory
-    imagedir = ""
-    # relative path to image directory from current docname (used at writing docs)
-    imgpath = ""
 
     def __init__(self, app):
         self.env = app.env
@@ -74,6 +70,10 @@ class Builder(object):
 
         # images that need to be copied over (source -> dest)
         self.images = {}
+        # basename of images directory
+        imagedir = ""
+        # relative path to image directory from current docname (used at writing docs)
+        imgpath = ""
 
         # these get set later
         self.parallel_ok = False

sphinx/builders/html.py

@@ -73,7 +73,6 @@ class StandaloneHTMLBuilder(Builder):
     link_suffix = '.html'  # defaults to matching out_suffix
     indexer_format = js_index
     indexer_dumps_unicode = True
-    imagedir = '_images'
     supported_image_types = ['image/svg+xml', 'image/png',
                              'image/gif', 'image/jpeg']
     searchindex_filename = 'searchindex.js'
@@ -96,6 +95,8 @@ class StandaloneHTMLBuilder(Builder):
         # a hash of all config values that, if changed, cause a full rebuild
         self.config_hash = ''
         self.tags_hash = ''
+        # basename of images directory
+        self.imagedir = '_images'
         # section numbers for headings in the currently visited document
         self.secnumbers = {}
         # currently written docname
@@ -1030,6 +1031,7 @@ class SerializingHTMLBuilder(StandaloneHTMLBuilder):
     def init(self):
         self.config_hash = ''
         self.tags_hash = ''
+        self.imagedir = '_images'
         self.theme = None       # no theme necessary
         self.templates = None   # no template bridge necessary
         self.init_translator_class()