feat: support [email protected] devel rocks

Includes a warning if using a devel base

docs/reference/rockcraft.yaml.rst

@@ -70,7 +70,7 @@ The rock version, used to tag the OCI image and name the rock file.
 ``base``
 --------
 
-**Type**: One of ``[email protected] | [email protected] | bare``
+**Type**: One of ``[email protected] | [email protected] | [email protected] | bare``
 
 **Required**: Yes
 
@@ -84,10 +84,14 @@ which is typically used with static binaries or
    The notation "ubuntu:<channel>" is also supported for some channels, but this
    format is deprecated and should be avoided.
 
+.. note::
+   Base ``[email protected]`` is still unstable and under active development. To use
+   it, ``build-base`` *must* be ``devel``.
+
 ``build-base``
 --------------
 
-**Type**: One of ``[email protected] | [email protected]``
+**Type**: One of ``[email protected] | [email protected] | devel``
 
 **Required**: Yes, if ``base`` is ``bare``
 
@@ -101,6 +105,11 @@ the value of ``base``.
    The notation "ubuntu:<channel>" is also supported for some channels, but this
    format is deprecated and should be avoided.
 
+.. note::
+   ``devel`` is a "special" value that means "the next Ubuntu version, currently
+   in development". This means that the contents of this system changes
+   frequently and should not be relied on for production rocks.
+
 ``license``
 -----------
 

rockcraft/models/project.py

@@ -117,6 +117,14 @@ def _validate_platform_set(cls, values: Mapping[str, Any]) -> Mapping[str, Any]:
 
 DEPRECATED_COLON_BASES = ["ubuntu:20.04", "ubuntu:22.04"]
 
+CURRENT_DEVEL_BASE = "[email protected]"
+
+DEVEL_BASE_WARNING = (
+    "The development build-base should only be used for testing purposes, "
+    "as its contents are bound to change with the opening of new Ubuntu releases, "
+    "suddenly and without warning."
+)
+
 
 class NameStr(pydantic.ConstrainedStr):
     """Constrained string type only accepting valid rock names."""
@@ -133,8 +141,8 @@ class Project(YamlModelMixin, BaseProject):
     description: str  # type: ignore[reportIncompatibleVariableOverride]
     rock_license: str = pydantic.Field(alias="license")
     platforms: dict[str, Any]
-    base: Literal["bare", "[email protected]", "[email protected]"]
-    build_base: Literal["[email protected]", "[email protected]"] | None
+    base: Literal["bare", "[email protected]", "[email protected]", "[email protected]"]
+    build_base: Literal["[email protected]", "[email protected]", "devel"] | None
     environment: dict[str, str] | None
     run_user: _RunUser
     services: dict[str, Service] | None
@@ -154,7 +162,12 @@ class Config(CraftBaseConfig):  # pylint: disable=too-few-public-methods
     def effective_base(self) -> bases.BaseName:
         """Get the Base name for craft-providers."""
         base = super().effective_base
-        name, channel = base.split("@")
+
+        if base == "devel":
+            name, channel = "ubuntu", "devel"
+        else:
+            name, channel = base.split("@")
+
         return bases.BaseName(name, channel)
 
     @pydantic.root_validator(pre=True)
@@ -197,6 +210,24 @@ def _validate_title(cls, title: str | None, values: Mapping[str, Any]) -> str:
             title = values.get("name", "")
         return cast(str, title)
 
+    @pydantic.root_validator(skip_on_failure=True)
+    @classmethod
+    def _validate_devel_base(cls, values: Mapping[str, Any]) -> Mapping[str, Any]:
+        """If 'base' is currently unstable, 'build-base' must be 'devel'."""
+        base = values.get("base")
+        build_base = values.get("build_base")
+
+        if base == CURRENT_DEVEL_BASE and build_base != "devel":
+            raise CraftValidationError(
+                f'To use the unstable base "{CURRENT_DEVEL_BASE}", '
+                '"build-base" must be "devel".'
+            )
+
+        if base == CURRENT_DEVEL_BASE:
+            craft_cli.emit.message(DEVEL_BASE_WARNING)
+
+        return values
+
     @pydantic.validator("build_base", always=True)
     @classmethod
     def _validate_build_base(

schema/rockcraft.json

@@ -35,7 +35,8 @@
       "enum": [
         "bare",
         "[email protected]",
-        "[email protected]"
+        "[email protected]",
+        "[email protected]"
       ],
       "type": "string"
     },
@@ -95,7 +96,8 @@
       "title": "Build-Base",
       "enum": [
         "[email protected]",
-        "[email protected]"
+        "[email protected]",
+        "devel"
       ],
       "type": "string"
     },

tests/integration/plugins/test_python_plugin.py

@@ -25,7 +25,7 @@
 from craft_parts.utils.os_utils import OsRelease
 
 from rockcraft import plugins
-from rockcraft.models.project import Project
+from rockcraft.models.project import CURRENT_DEVEL_BASE, Project
 from rockcraft.plugins.python_plugin import SITECUSTOMIZE_TEMPLATE
 from tests.testing.project import create_project
 from tests.util import ubuntu_only
@@ -60,10 +60,11 @@ def create_python_project(base, extra_part_props=None) -> Project:
         }
     }
 
-    return create_project(
-        base=base,
-        parts=parts,
-    )
+    build_base = None
+    if base == CURRENT_DEVEL_BASE:
+        build_base = "devel"
+
+    return create_project(base=base, parts=parts, build_base=build_base)
 
 
 @dataclass

tests/spread/general/base-devel/rockcraft.orig.yaml

@@ -0,0 +1,18 @@
+name: base-devel
+base: placeholder-base
+build-base: devel
+version: '0.1'
+summary: A project using the "devel" build-base
+description: A project using the "devel" build-base
+license: GPL-3.0
+platforms:
+  amd64:
+
+parts:
+  from-chisel-slices:
+    plugin: nil
+    stage-packages: [dotnet-runtime-8.0_libs]
+
+  from-deb:
+    plugin: nil
+    stage-packages: [hello]

tests/spread/general/base-devel/task.yaml

@@ -0,0 +1,12 @@
+summary: Build rocks using the "devel" build-base
+environment:
+  BASE/base_2404: "[email protected]"
+  BASE/bare: "bare"
+execute: |
+  # Make sure the yaml file has the "placeholder-base" string, and replace
+  # it with the correct base.
+  grep placeholder-base rockcraft.orig.yaml
+  sed "s/placeholder-base/$BASE/" rockcraft.orig.yaml  > rockcraft.yaml
+
+  # Build the rock & load it into docker
+  run_rockcraft pack

tests/spread/general/plugin-python/base-2404/rockcraft.yaml

@@ -0,0 +1,5 @@
+name: base-2404
+base: [email protected]
+build-base: devel
+
+# Remaining contents will come from "parts.yaml"

tests/spread/general/plugin-python/task.yaml

@@ -2,6 +2,7 @@ summary: Python plugin tests
 environment:
   SCENARIO/base_2004: base-2004
   SCENARIO/base_2204: base-2204
+  SCENARIO/base_2404: base-2404
   SCENARIO/bare_build_2004: bare-build-2004
   SCENARIO/bare_build_2204: bare-build-2204
 execute: |

tests/unit/test_project.py

@@ -31,7 +31,13 @@
 
 from rockcraft.errors import ProjectLoadError
 from rockcraft.models import Project
-from rockcraft.models.project import INVALID_NAME_MESSAGE, Platform, load_project
+from rockcraft.models.project import (
+    CURRENT_DEVEL_BASE,
+    DEVEL_BASE_WARNING,
+    INVALID_NAME_MESSAGE,
+    Platform,
+    load_project,
+)
 from rockcraft.pebble import Service
 
 _ARCH_MAPPING = {"x86": "amd64", "x64": "amd64"}
@@ -233,7 +239,8 @@ def test_project_base_invalid(yaml_loaded_data):
         load_project_yaml(yaml_loaded_data)
     assert str(err.value) == (
         "Bad rockcraft.yaml content:\n"
-        "- unexpected value; permitted: 'bare', '[email protected]', '[email protected]' (in field 'base')"
+        "- unexpected value; permitted: 'bare', '[email protected]', "
+        "'[email protected]', '[email protected]' (in field 'base')"
     )
 
 
@@ -706,3 +713,36 @@ def test_project_get_build_plan(yaml_loaded_data, platforms, expected_build_info
     yaml_loaded_data["platforms"] = platforms
     project = Project.unmarshal(yaml_loaded_data)
     assert project.get_build_plan() == expected_build_infos
+
+
+def test_project_devel_base(yaml_loaded_data):
+    yaml_loaded_data["base"] = CURRENT_DEVEL_BASE
+    yaml_loaded_data["build-base"] = "[email protected]"
+
+    with pytest.raises(CraftValidationError) as err:
+        _ = Project.unmarshal(yaml_loaded_data)
+
+    expected = (
+        f'To use the unstable base "{CURRENT_DEVEL_BASE}", '
+        f'"build-base" must be "devel".'
+    )
+    assert str(err.value) == expected
+
+
+def test_get_effective_devel_base(yaml_loaded_data):
+    yaml_loaded_data["base"] = CURRENT_DEVEL_BASE
+    yaml_loaded_data["build-base"] = "devel"
+    project = Project.unmarshal(yaml_loaded_data)
+
+    base = project.effective_base
+    assert base.name == "ubuntu"
+    assert base.version == "devel"
+
+
+def test_devel_base_warning(yaml_loaded_data, emitter):
+    yaml_loaded_data["base"] = CURRENT_DEVEL_BASE
+    yaml_loaded_data["build-base"] = "devel"
+    del yaml_loaded_data["entrypoint-service"]
+    _ = Project.unmarshal(yaml_loaded_data)
+
+    emitter.assert_message(DEVEL_BASE_WARNING)