feat(lifecycle): add deprecated snap command

snapcraft/application.py

@@ -34,6 +34,7 @@
 from craft_providers import bases
 from overrides import override
 
+import snapcraft.commands
 from snapcraft import cli, errors, models, services
 from snapcraft.commands import unimplemented
 from snapcraft.models import Architecture
@@ -253,8 +254,8 @@ def main() -> int:
             craft_app_commands.lifecycle.StageCommand,
             craft_app_commands.lifecycle.PrimeCommand,
             craft_app_commands.lifecycle.PackCommand,
+            snapcraft.commands.lifecycle.SnapCommand,  # Hidden (legacy compatibility)
             unimplemented.RemoteBuild,
-            unimplemented.Snap,  # Hidden (legacy compatibility)
             unimplemented.Plugins,
             unimplemented.ListPlugins,
             unimplemented.Try,

snapcraft/commands/__init__.py

@@ -17,8 +17,10 @@
 """Snapcraft commands."""
 
 from . import core22, legacy
+from .lifecycle import SnapCommand
 
 __all__ = [
     "core22",
     "legacy",
+    "SnapCommand",
 ]

snapcraft/commands/lifecycle.py

@@ -0,0 +1,48 @@
+# -*- Mode:Python; indent-tabs-mode:nil; tab-width:4 -*-
+#
+# Copyright 2024 Canonical Ltd.
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 3 as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+"""Snapcraft lifecycle commands."""
+
+import argparse
+from typing import Any
+
+import craft_application.commands
+from craft_cli import emit
+from typing_extensions import override
+
+# pylint: disable=too-many-ancestors
+
+
+class SnapCommand(craft_application.commands.lifecycle.PackCommand):
+    """Deprecated legacy command to pack the final snap payload."""
+
+    name = "snap"
+    hidden = True
+
+    @override
+    def _run(
+        self,
+        parsed_args: argparse.Namespace,
+        step_name: str | None = None,
+        **kwargs: Any,
+    ) -> None:
+        emit.progress(
+            "Warning: the 'snap' command is deprecated and will be removed "
+            "in a future release of Snapcraft. Please use 'pack' instead.",
+            permanent=True,
+        )
+
+        super()._run(parsed_args, step_name, **kwargs)

snapcraft/commands/unimplemented.py

@@ -180,48 +180,6 @@ class Validate(
     pass
 
 
-class Build(
-    UnimplementedMixin, commands.core22.BuildCommand
-):  # noqa: D101 (missing docstring)
-    pass
-
-
-class Clean(
-    UnimplementedMixin, commands.core22.CleanCommand
-):  # noqa: D101 (missing docstring)
-    pass
-
-
-class Pack(
-    UnimplementedMixin, commands.core22.PackCommand
-):  # noqa: D101 (missing docstring)
-    pass
-
-
-class Prime(
-    UnimplementedMixin, commands.core22.PrimeCommand
-):  # noqa: D101 (missing docstring)
-    pass
-
-
-class Pull(
-    UnimplementedMixin, commands.core22.PullCommand
-):  # noqa: D101 (missing docstring)
-    pass
-
-
-class Snap(
-    UnimplementedMixin, commands.core22.SnapCommand
-):  # noqa: D101 (missing docstring)
-    pass
-
-
-class Stage(
-    UnimplementedMixin, commands.core22.StageCommand
-):  # noqa: D101 (missing docstring)
-    pass
-
-
 class Try(
     UnimplementedMixin, commands.core22.TryCommand
 ):  # noqa: D101 (missing docstring)

tests/unit/commands/test_lifecycle.py

@@ -19,30 +19,23 @@
 
 import pytest
 
-from snapcraft.commands.core22.lifecycle import (
-    BuildCommand,
-    CleanCommand,
-    PackCommand,
-    PrimeCommand,
-    PullCommand,
-    SnapCommand,
-    StageCommand,
-    TryCommand,
-)
+import snapcraft.commands.core22.lifecycle as core22_lifecycle
+from snapcraft.application import APP_METADATA
+from snapcraft.commands import lifecycle
 
 
 @pytest.mark.parametrize(
     "cmd_name,cmd_class",
     [
-        ("pull", PullCommand),
-        ("build", BuildCommand),
-        ("stage", StageCommand),
-        ("prime", PrimeCommand),
-        ("clean", CleanCommand),
-        ("try", TryCommand),
+        ("pull", core22_lifecycle.PullCommand),
+        ("build", core22_lifecycle.BuildCommand),
+        ("stage", core22_lifecycle.StageCommand),
+        ("prime", core22_lifecycle.PrimeCommand),
+        ("clean", core22_lifecycle.CleanCommand),
+        ("try", core22_lifecycle.TryCommand),
     ],
 )
-def test_lifecycle_command(cmd_name, cmd_class, mocker):
+def test_core22_lifecycle_command(cmd_name, cmd_class, mocker):
     lifecycle_run_mock = mocker.patch("snapcraft.parts.lifecycle.run")
     cmd = cmd_class(None)
     cmd.run(argparse.Namespace(parts=["part1", "part2"]))
@@ -54,11 +47,11 @@ def test_lifecycle_command(cmd_name, cmd_class, mocker):
 @pytest.mark.parametrize(
     "cmd_name,cmd_class",
     [
-        ("pack", PackCommand),
-        ("snap", SnapCommand),
+        ("pack", core22_lifecycle.PackCommand),
+        ("snap", core22_lifecycle.SnapCommand),
     ],
 )
-def test_pack_command(mocker, cmd_name, cmd_class):
+def test_core22_pack_command(mocker, cmd_name, cmd_class):
     lifecycle_run_mock = mocker.patch("snapcraft.parts.lifecycle.run")
     cmd = cmd_class(None)
     cmd.run(argparse.Namespace(directory=None, output=None, compression=None))
@@ -72,11 +65,11 @@ def test_pack_command(mocker, cmd_name, cmd_class):
 @pytest.mark.parametrize(
     "cmd_name,cmd_class",
     [
-        ("pack", PackCommand),
-        ("snap", SnapCommand),
+        ("pack", core22_lifecycle.PackCommand),
+        ("snap", core22_lifecycle.SnapCommand),
     ],
 )
-def test_pack_command_with_output(mocker, cmd_name, cmd_class):
+def test_core22_pack_command_with_output(mocker, cmd_name, cmd_class):
     lifecycle_run_mock = mocker.patch("snapcraft.parts.lifecycle.run")
     pack_mock = mocker.patch("snapcraft.pack.pack_snap")
     cmd = cmd_class(None)
@@ -90,10 +83,24 @@ def test_pack_command_with_output(mocker, cmd_name, cmd_class):
     assert pack_mock.mock_calls == []
 
 
-def test_pack_command_with_directory(mocker):
+def test_core22_pack_command_with_directory(mocker):
     lifecycle_run_mock = mocker.patch("snapcraft.parts.lifecycle.run")
     pack_mock = mocker.patch("snapcraft.pack.pack_snap")
-    cmd = PackCommand(None)
+    cmd = core22_lifecycle.PackCommand(None)
     cmd.run(argparse.Namespace(directory=".", output=None, compression=None))
     assert lifecycle_run_mock.mock_calls == []
     assert pack_mock.mock_calls[0] == call(".", output=None)
+
+
+def test_snap_command_fallback(tmp_path, emitter, mocker, fake_services):
+    """Test that the snap command is falling back to the pack command."""
+    parsed_args = argparse.Namespace(parts=[], output=tmp_path)
+    mock_pack = mocker.patch("craft_application.commands.lifecycle.PackCommand._run")
+    cmd = lifecycle.SnapCommand({"app": APP_METADATA, "services": fake_services})
+    cmd.run(parsed_args=parsed_args)
+    mock_pack.assert_called_once()
+    emitter.assert_progress(
+        "Warning: the 'snap' command is deprecated and will be removed "
+        "in a future release of Snapcraft. Please use 'pack' instead.",
+        permanent=True,
+    )

tests/unit/conftest.py

@@ -442,3 +442,14 @@ def package_service(default_project, default_factory):
 
 
 # pylint: enable=import-outside-toplevel
+
+
+@pytest.fixture()
+def fake_services(default_factory, lifecycle_service, package_service):
+    lifecycle_service.setup()
+    default_factory.lifecycle = lifecycle_service
+
+    package_service.setup()
+    default_factory.package = package_service
+
+    return default_factory