1 files changed, 21 insertions, 1 deletions
diff --git a/sphinx/util/docutils.py b/sphinx/util/docutils.py
index a745e058a..f4dd96158 100644
--- a/sphinx/util/docutils.py
+++ b/sphinx/util/docutils.py
@@ -18,7 +18,7 @@ from contextlib import contextmanager
 
 import docutils
 from docutils.languages import get_language
-from docutils.statemachine import ViewList
+from docutils.statemachine import StateMachine, ViewList
 from docutils.parsers.rst import directives, roles, convert_directive_function
 from docutils.utils import Reporter
 
@@ -33,6 +33,7 @@ if False:
     # For type annotation
     from typing import Any, Callable, Dict, Iterator, List, Tuple  # NOQA
     from docutils import nodes  # NOQA
+    from docutils.statemachine import State  # NOQA
     from sphinx.environment import BuildEnvironment  # NOQA
     from sphinx.io import SphinxFileInput  # NOQA
 
@@ -216,3 +217,22 @@ def directive_helper(obj, has_content=None, argument_spec=None, option_spec=None
             raise ExtensionError(__('when adding directive classes, no '
                                     'additional arguments may be given'))
         return obj
+
+
+@contextmanager
+def switch_source_input(state, content):
+    # type: (State, ViewList) -> None
+    """Switch current source input of state temporarily."""
+    try:
+        # remember the original ``get_source_and_line()`` method
+        get_source_and_line = state.memo.reporter.get_source_and_line
+
+        # replace it by new one
+        state_machine = StateMachine([], None)
+        state_machine.input_lines = content
+        state.memo.reporter.get_source_and_line = state_machine.get_source_and_line
+
+        yield
+    finally:
+        # restore the method
+        state.memo.reporter.get_source_and_line = get_source_and_line