Add support for macOS 11.0 as a target.

README.rst

@@ -181,17 +181,17 @@ shell scripts listed above are available for your build and test.
 Build options are controlled mainly by the following environment
 variables:
 
-* ``MB_PYTHON_VER`` sets the Python version targeted: ``major.minor.patch``
+* ``MB_PYTHON_VERSION`` sets the Python version targeted: ``major.minor.patch``
   for CPython, or ``pypy-major.minor`` for PyPy.
-* ``MB_PYTHON_OSX_VER`` sets the minimum macOS SDK version for any C
-  extensions. For CPython targets it may be set to 10.6 or 10.9, provided a
+* ``MB_PYTHON_OSX_VER`` sets the minimum macOS SDK version for any C extensions.
+  For CPython targets it may be set to 10.6, 10.9 or 11.0, provided a
   corresponding Python build is available at `python.org
   <https://www.python.org/downloads/mac-osx/>`_. It defaults to the highest
   version available. It's ignored for PyPy targets.
 * ``PLAT`` sets the architectures built for any C extensions: ``x86_64`` or
-  ``intel`` for 64-bit or 64/32-bit respectively. It defaults to the same
-  arches as the target Python version: 64-bit for CPython macOS 10.9 or PyPy,
-  and 64/32-bit for CPython 10.6.
+  ``intel`` for 64-bit or 64/32-bit respectively. It defaults to the same arches
+  as the target Python version: arm64 for macOS 11.0; x86_64 for CPython
+  macOS 10.9 or PyPy; and 64/32-bit for CPython 10.6.
 
 In most cases it's best to rely on the defaults for ``MB_PYTHON_OSX_VER`` and
 ``PLAT``, rather than setting them explicitly. Examples of exceptions to this

osx_utils.sh

@@ -223,7 +223,7 @@ function get_macpython_osx_ver {
 }
 
 function macpython_arch_for_version {
-    # echo arch (intel or x86_64) that a version of Python is expected
+    # echo arch (intel, x86_64 or arm64) that a version of Python is expected
     # to be built for
     # Parameters
     #   $py_ver     Python version, in the format (major.minor.patch) for
@@ -238,8 +238,10 @@ function macpython_arch_for_version {
             echo "intel"
         elif [[ "$py_osx_ver" == "10.9" ]]; then
             echo "x86_64"
+        elif [[ "$py_osx_ver" == "11.0" ]]; then
+            echo "arm64"
         else
-            echo "Unexpected CPython macOS version: ${py_osx_ver}, supported values: 10.6 and 10.9"
+            echo "Unexpected CPython macOS version: ${py_osx_ver}, supported values: 10.6, 10.9, 11.0"
             exit 1
         fi
     else

tests/test_osx_utils.sh

@@ -32,6 +32,7 @@
 [ "$(macpython_arch_for_version 2.7 10.6)" == "intel" ] || ingest
 [ "$(macpython_arch_for_version 2.7 10.9)" == "x86_64" ] || ingest
 [ "$(macpython_arch_for_version pypy-2.7)" == "x86_64" ] || ingest
+[ "$(macpython_arch_for_version 3.10 11.0)" == "arm64" ] || ingest
 
 # test lookup of arch / min macOS versions from installed Python distutils tag
 [ "$(get_macpython_arch macosx-10.6-intel)" == "intel" ] || ingest