Fixed #24098 -- Added no-op attributes to RunPython and RunSQL

Thanks Loïc Bistuer and Tim Graham for the discussion and review.

2 files changed, 21 insertions, 0 deletions

diff --git a/docs/ref/migration-operations.txt b/docs/ref/migration-operations.txt
index 46b87f44c4..dcac7f26a6 100644
--- a/docs/ref/migration-operations.txt
+++ b/docs/ref/migration-operations.txt
@@ -245,6 +245,14 @@ operation that adds that field and so will try to run it again).
     The ability to pass parameters to the ``sql`` and ``reverse_sql`` queries
     was added.
 
+.. attribute:: RunSQL.noop
+
+    .. versionadded:: 1.8
+
+    Pass the ``RunSQL.noop`` attribute to ``sql`` or ``reverse_sql`` when you
+    want the operation not to do anything in the given direction. This is
+    especially useful in making the operation reversible.
+
 .. _sqlparse: https://pypi.python.org/pypi/sqlparse
 
 RunPython
@@ -321,6 +329,14 @@ set ``atomic=False``.
     ``schema_editor.connection.alias``, where ``schema_editor`` is the second
     argument to your function).
 
+.. staticmethod:: RunPython.noop
+
+    .. versionadded:: 1.8
+
+    Pass the ``RunPython.noop`` method to ``code`` or ``reverse_code`` when
+    you want the operation not to do anything in the given direction. This is
+    especially useful in making the operation reversible.
+
 SeparateDatabaseAndState
 ------------------------
 
diff --git a/docs/releases/1.8.txt b/docs/releases/1.8.txt
index 3a522ee741..427ec5d493 100644
--- a/docs/releases/1.8.txt
+++ b/docs/releases/1.8.txt
@@ -457,6 +457,11 @@ Migrations
 * A :ref:`generic mechanism to handle the deprecation of model fields
   <migrations-removing-model-fields>` was added.
 
+* The :attr:`RunPython.noop <django.db.migrations.operations.RunPython.noop>`
+  and :meth:`RunSQL.noop() <django.db.migrations.operations.RunSQL.noop>` class
+  attribute/method were added to ease in making ``RunPython`` and ``RunSQL``
+  operations reversible.
+
 Models
 ^^^^^^