CPack: Change CPACK_PRODUCTBUILD_DOMAINS default to true (CMP0161)

Fixes: #23351

4 files changed, 45 insertions, 2 deletions

diff --git a/Help/cpack_gen/productbuild.rst b/Help/cpack_gen/productbuild.rst
index 48a9b44..ee8a03f 100644
--- a/Help/cpack_gen/productbuild.rst
+++ b/Help/cpack_gen/productbuild.rst
@@ -91,8 +91,9 @@ macOS using ProductBuild:
  .. versionadded:: 3.23
 
  This option enables more granular control over where the product may be
- installed. When it is set to true, a ``domains`` element of the following
- form will be added to the productbuild Distribution XML:
+ installed. When it is set to true (see policy :policy:`CMP0161`), a
+ ``domains`` element of the following form will be added to the
+ productbuild Distribution XML:
 
  .. code-block:: xml
 
diff --git a/Help/manual/cmake-policies.7.rst b/Help/manual/cmake-policies.7.rst
index d37c855..bb6cfd4 100644
--- a/Help/manual/cmake-policies.7.rst
+++ b/Help/manual/cmake-policies.7.rst
@@ -57,6 +57,7 @@ Policies Introduced by CMake 3.29
 .. toctree::
    :maxdepth: 1
 
+   CMP0161: CPACK_PRODUCTBUILD_DOMAINS defaults to true. </policy/CMP0161>
    CMP0160: More read-only target properties now error when trying to set them. </policy/CMP0160>
    CMP0159: file(STRINGS) with REGEX updates CMAKE_MATCH_<n>. </policy/CMP0159>
    CMP0158: add_test() honors CMAKE_CROSSCOMPILING_EMULATOR only when cross-compiling. </policy/CMP0158>
diff --git a/Help/policy/CMP0161.rst b/Help/policy/CMP0161.rst
new file mode 100644
index 0000000..34bb64c
--- /dev/null
+++ b/Help/policy/CMP0161.rst
@@ -0,0 +1,36 @@
+CMP0161
+-------
+
+.. versionadded:: 3.29
+
+The :variable:`CPACK_PRODUCTBUILD_DOMAINS` variable defaults to true.
+
+Before CMake 3.29, the :variable:`CPACK_PRODUCTBUILD_DOMAINS` variable is
+unset by default.  When using the :cpack_gen:`CPack productbuild Generator`,
+this disables the use of the ``domains`` attribute in the productbuild
+Distribution XML, and falls back to the ``auth`` attribute instead.
+These attributes control where a productbuild package is allowed to be
+installed.  But the ``auth`` attribute has been deprecated by Apple,
+so projects should migrate to using ``domains`` instead.
+
+CMake 3.29 and above prefer to use a default value of true for
+:variable:`CPACK_PRODUCTBUILD_DOMAINS`, which means ``domains`` will be used
+by default unless the project explicitly sets
+:variable:`CPACK_PRODUCTBUILD_DOMAINS` to false.
+This policy provides compatibility with projects that enabled the
+:cpack_gen:`CPack productbuild Generator`, but did not explicitly set
+:variable:`CPACK_PRODUCTBUILD_DOMAINS`.
+
+The ``OLD`` behavior for this policy is to leave
+:variable:`CPACK_PRODUCTBUILD_DOMAINS` unset if it hasn't been set.
+The ``NEW`` behavior for this policy is to use a default value of true for
+:variable:`CPACK_PRODUCTBUILD_DOMAINS`.
+
+.. |INTRODUCED_IN_CMAKE_VERSION| replace:: 3.29
+.. |WARNS_OR_DOES_NOT_WARN| replace:: warns
+.. include:: STANDARD_ADVICE.txt
+Note that a warning will only be emitted if the
+:variable:`CPACK_BINARY_PRODUCTBUILD <CPACK_BINARY_<GENNAME>>` variable is
+set to true and the project is being built for an Apple platform.
+
+.. include:: DEPRECATED.txt
diff --git a/Help/release/dev/productbuild-domains-policy.rst b/Help/release/dev/productbuild-domains-policy.rst
new file mode 100644
index 0000000..2009453
--- /dev/null
+++ b/Help/release/dev/productbuild-domains-policy.rst
@@ -0,0 +1,5 @@
+productbuild-domains-policy
+---------------------------
+
+* The :variable:`CPACK_PRODUCTBUILD_DOMAINS` variable now defaults to true.
+  See policy :policy:`CMP0161`.