feat: use craft-platforms for build plans (#5111)

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versions: `py39`, `py310`, `py311`, `py312`)

-----

---------

Co-authored-by: Alex Lowe <alex.lowe@canonical.com>

requirements-devel.txt

@@ -29,7 +29,7 @@ craft-archives==2.0.0
 craft-cli==2.7.0
 craft-grammar==2.0.1
 craft-parts==2.1.2
-craft-platforms==0.1.1
+craft-platforms==0.4.0
 craft-providers==2.0.4
 craft-store==3.0.2
 cryptography==43.0.1

requirements-docs.txt

@@ -24,7 +24,7 @@ craft-archives==2.0.0
 craft-cli==2.7.0
 craft-grammar==2.0.1
 craft-parts==2.1.2
-craft-platforms==0.1.1
+craft-platforms==0.4.0
 craft-providers==2.0.4
 craft-store==3.0.2
 cryptography==43.0.1

requirements.txt

@@ -12,7 +12,7 @@ craft-archives==2.0.0
 craft-cli==2.7.0
 craft-grammar==2.0.1
 craft-parts==2.1.2
-craft-platforms==0.1.1
+craft-platforms==0.4.0
 craft-providers==2.0.4
 craft-store==3.0.2
 cryptography==43.0.1

setup.py

@@ -103,7 +103,7 @@ def recursive_data_files(directory, install_directory):
     "craft-cli~=2.6",
     "craft-grammar>=2.0.1,<3.0.0",
     "craft-parts>=2.1.2,<3.0.0",
-    "craft-platforms~=0.1",
+    "craft-platforms~=0.4",
     "craft-providers>=2.0.4,<3.0.0",
     "craft-store>=3.0.2,<4.0.0",
     "docutils<0.20",  # Frozen until we can update sphinx dependencies.

snapcraft/models/project.py

@@ -32,6 +32,7 @@
 )
 from craft_cli import emit
 from craft_grammar.models import Grammar  # type: ignore[import-untyped]
+from craft_platforms import Platforms, snap
 from craft_providers import bases
 from pydantic import ConfigDict, PrivateAttr, StringConstraints
 from typing_extensions import Annotated, Self, override
@@ -277,6 +278,14 @@ def _get_partitions_from_components(
     return None
 
 
+def _validate_mandatory_base(base: str | None, snap_type: str | None) -> None:
+    """Validate that the base is specified, if required by the snap_type."""
+    if (base is not None) ^ (snap_type not in ["base", "kernel", "snapd"]):
+        raise ValueError(
+            "Snap base must be declared when type is not base, kernel or snapd"
+        )
+
+
 class Socket(models.CraftBaseModel):
     """Snapcraft app socket definition."""
 
@@ -714,12 +723,7 @@ def _validate_adoptable_fields(self) -> Self:
 
     @pydantic.model_validator(mode="after")
     def _validate_mandatory_base(self):
-        snap_type = self.type
-        base = self.base
-        if (base is not None) ^ (snap_type not in ["base", "kernel", "snapd"]):
-            raise ValueError(
-                "Snap base must be declared when type is not base, kernel or snapd"
-            )
+        _validate_mandatory_base(self.base, self.type)
         return self
 
     @pydantic.field_validator("name")
@@ -1138,6 +1142,7 @@ class SnapcraftBuildPlanner(models.BuildPlanner):
     base: str | None = None
     build_base: str | None = None
     name: str
+    type: Literal["app", "base", "gadget", "kernel", "snapd"] | None = None
     platforms: dict[str, Platform] | None = None  # type: ignore[assignment]
     architectures: list[str | Architecture] | None = None
     project_type: str | None = pydantic.Field(default=None, alias="type")
@@ -1192,7 +1197,6 @@ def _validate_all_platforms(
 
     def get_build_plan(self) -> list[BuildInfo]:
         """Get the build plan for this project."""
-        build_infos: list[BuildInfo] = []
         effective_base = SNAPCRAFT_BASE_TO_PROVIDER_BASE[
             str(
                 get_effective_base(
@@ -1205,8 +1209,6 @@ def get_build_plan(self) -> list[BuildInfo]:
             )
         ].value
 
-        base = bases.BaseName("ubuntu", effective_base)
-
         # set default value
         if self.platforms is None:
             self.platforms = {
@@ -1221,16 +1223,31 @@ def get_build_plan(self) -> list[BuildInfo]:
                     Platform.from_architectures(self.architectures)
                 )
 
-        for platform_entry, platform in self.platforms.items():
-            for build_for in platform.build_for or [SnapArch(platform_entry).value]:
-                for build_on in platform.build_on or [SnapArch(platform_entry).value]:
-                    build_infos.append(
-                        BuildInfo(
-                            platform=platform_entry,
-                            build_on=build_on,
-                            build_for=build_for,
-                            base=base,
-                        )
-                    )
+        platforms = cast(
+            Platforms,
+            {name: platform.marshal() for name, platform in self.platforms.items()},
+        )
 
-        return build_infos
+        # In _validate_mandatory_base, we ensure that the possible values of
+        # 'base' and 'snap_type' are narrowed so they'll always match one of
+        # the two overloads of get_platforms_snap_build_plan.  But, pyright and
+        # mypy aren't smart enough to realize this, so we need the type checker
+        # ignores.
+        _validate_mandatory_base(self.base, self.type)
+        return [
+            BuildInfo(
+                platform=buildinfo.platform,
+                build_on=str(buildinfo.build_on),
+                build_for=str(buildinfo.build_for),
+                base=bases.BaseName(
+                    name=buildinfo.build_base.distribution,
+                    version=buildinfo.build_base.series,
+                ),
+            )
+            for buildinfo in snap.get_platforms_snap_build_plan(  # pyright: ignore[reportCallIssue]
+                base=self.base,  # type: ignore[arg-type]
+                build_base=self.build_base,
+                snap_type=self.type,  # type: ignore[arg-type]
+                platforms=platforms,
+            )
+        ]

tests/unit/models/test_projects.py

@@ -2486,40 +2486,6 @@ def test_platform_default():
     ]
 
 
-def test_build_planner_get_build_plan_base(mocker):
-    """Test `get_build_plan()` uses the correct base."""
-    mock_get_effective_base = mocker.patch(
-        "snapcraft.models.project.get_effective_base", return_value="core24"
-    )
-    planner = snapcraft.models.project.SnapcraftBuildPlanner.model_validate(
-        {
-            "name": "test-snap",
-            "base": "test-base",
-            "build-base": "test-build-base",
-            "platforms": {"amd64": None},
-            "project_type": "test-type",
-        }
-    )
-
-    actual_build_infos = planner.get_build_plan()
-
-    assert actual_build_infos == [
-        BuildInfo(
-            platform="amd64",
-            build_on="amd64",
-            build_for="amd64",
-            base=BaseName(name="ubuntu", version="24.04"),
-        )
-    ]
-    mock_get_effective_base.assert_called_once_with(
-        base="test-base",
-        build_base="test-build-base",
-        project_type="test-type",
-        name="test-snap",
-        translate_devel=False,
-    )
-
-
 def test_project_platform_error_has_context():
     """Platform validation errors include which platform entry is invalid."""
     error = r"build-on\n  Field required"