Merge ~raharper/curtin:fix/ppc64-mac-partition into curtin:master

[Ryan Harper]

block-schema: allow 'mac' as partition table type

On PPC64, the partition table on the live iso is 'mac'.
Add this value to the partition type schema.

LP: #1845611

[Dan Watkins (oddbloke)]

review: Approve

[Server Team CI bot (server-team-bot)]

PASSED: Continuous integration, rev:ce54496580b8765ceeae1846a86b0a7db0068673
https://jenkins.ubuntu.com/server/job/curtin-ci/3716/
Executed test runs:
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-arm64/3716/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-ppc64el/3716/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=metal-s390x/3716/
    SUCCESS: https://jenkins.ubuntu.com/server/job/curtin-ci/nodes=torkoal/3716/

Click here to trigger a rebuild:
https://jenkins.ubuntu.com/server/job/curtin-ci/3716//rebuild

review: Approve (continuous-integration)

diff --git a/curtin/block/schemas.py b/curtin/block/schemas.py
index f754ccc..3594a40 100644
--- a/curtin/block/schemas.py
+++ b/curtin/block/schemas.py
@@ -14,7 +14,7 @@ definitions = {
     'devices': {'type': 'array', 'items': {'$ref': '#/definitions/ref_id'}},
     'name': {'type': 'string'},
     'preserve': {'type': 'boolean'},
-    'ptable': {'type': 'string', 'enum': ['dos', 'gpt', 'msdos']},
+    'ptable': {'type': 'string', 'enum': ['dos', 'gpt', 'mac', 'msdos']},
     'size': {'type': ['string', 'number'],
              'minimum': 1,
              'pattern': r'^([1-9]\d*(.\d+)?|\d+.\d+)(K|M|G|T)?B?'},
diff --git a/tests/unittests/test_storage_config.py b/tests/unittests/test_storage_config.py
index fa8a4af..0ae5107 100644
--- a/tests/unittests/test_storage_config.py
+++ b/tests/unittests/test_storage_config.py
@@ -42,6 +42,17 @@ class TestStorageConfigSchema(CiTestCase):
         config = {'config': [disk], 'version': 1}
         storage_config.validate_config(config)
 
+    @skipUnlessJsonSchema()
+    def test_disk_schema_accepts_mac_partition_table(self):
+        disk = {
+            "id": "disk-vdc",
+            "path": "/dev/vdc",
+            "type": "disk",
+            "ptable": "mac",
+        }
+        config = {'config': [disk], 'version': 1}
+        storage_config.validate_config(config)
+
 
 class TestProbertParser(CiTestCase):