Deprecate unused and untested sphinx.util functions

sphinx.util.attrdict: Last use removed in
b09e628b0f.

sphinx.util.PeekableIterator: Last use removed in
85b8a451a6.

CHANGES

@@ -50,9 +50,11 @@ Deprecated
 * ``sphinx.ext.doctest.doctest_encode()``
 * ``sphinx.io.SphinxRSTFileInput``
 * ``sphinx.testing.util.remove_unicode_literal()``
+* ``sphinx.util.attrdict``
 * ``sphinx.util.force_decode()``
 * ``sphinx.util.get_matching_docs()`` is deprecated
 * ``sphinx.util.osutil.walk()``
+* ``sphinx.util.PeekableIterator``
 * ``sphinx.util.pycompat.u``
 * ``sphinx.writers.latex.LaTeXTranslator.babel_defmacro()``
 * ``sphinx.writers.latex.TextTranslator._make_visit_admonition()``

doc/extdev/index.rst

@@ -162,6 +162,11 @@ The following is a list of deprecated interfaces.
      - 4.0
      - N/A
 
+   * - ``sphinx.util.attrdict``
+     - 2.0
+     - 4.0
+     - N/A
+
    * - ``sphinx.util.force_decode()``
      - 2.0
      - 4.0
@@ -182,6 +187,11 @@ The following is a list of deprecated interfaces.
      - 4.0
      - N/A
 
+   * - ``sphinx.util.PeekableIterator``
+     - 2.0
+     - 4.0
+     - N/A
+
    * - ``sphinx.application.Sphinx._setting_up_extension``
      - 2.0
      - 3.0

sphinx/util/__init__.py

@@ -499,6 +499,11 @@ def force_decode(string, encoding):
 
 
 class attrdict(dict):
+    def __init__(self, *args, **kwargs):
+        super(attrdict, self).__init__(*args, **kwargs)
+        warnings.warn('The attrdict class is deprecated.',
+                      RemovedInSphinx40Warning, stacklevel=2)
+
     def __getattr__(self, key):
         # type: (unicode) -> unicode
         return self[key]
@@ -573,6 +578,8 @@ class PeekableIterator:
         # type: (Iterable) -> None
         self.remaining = deque()  # type: deque
         self._iterator = iter(iterable)
+        warnings.warn('PeekableIterator is deprecated.',
+                      RemovedInSphinx40Warning, stacklevel=2)
 
     def __iter__(self):
         # type: () -> PeekableIterator