fix: sync command should really add --sync option to installer

src/poetry/console/commands/install.py

@@ -93,6 +93,19 @@ def activated_groups(self) -> set[str]:
     def _alternative_sync_command(self) -> str:
         return "poetry sync"
 
+    @property
+    def _with_synchronization(self) -> bool:
+        with_synchronization = self.option("sync")
+        if with_synchronization:
+            self.line_error(
+                "<warning>The `<fg=yellow;options=bold>--sync</>` option is"
+                " deprecated and slated for removal in the next minor release"
+                " after June 2025, use the"
+                f" `<fg=yellow;options=bold>{self._alternative_sync_command}</>`"
+                " command instead.</warning>"
+            )
+        return bool(with_synchronization)
+
     def handle(self) -> int:
         from poetry.core.masonry.utils.module import ModuleOrPackageNotFoundError
 
@@ -150,20 +163,10 @@ def handle(self) -> int:
 
         self.installer.extras(extras)
 
-        with_synchronization = self.option("sync")
-        if with_synchronization:
-            self.line_error(
-                "<warning>The `<fg=yellow;options=bold>--sync</>` option is"
-                " deprecated and slated for removal in the next minor release"
-                " after June 2025, use the"
-                f" `<fg=yellow;options=bold>{self._alternative_sync_command}</>`"
-                " command instead.</warning>"
-            )
-
         self.installer.only_groups(self.activated_groups)
         self.installer.skip_directory(self.option("no-directory"))
         self.installer.dry_run(self.option("dry-run"))
-        self.installer.requires_synchronization(with_synchronization)
+        self.installer.requires_synchronization(self._with_synchronization)
         self.installer.executor.enable_bytecode_compilation(self.option("compile"))
         self.installer.verbose(self.io.is_verbose())
 

src/poetry/console/commands/self/sync.py

@@ -29,3 +29,7 @@ class SelfSyncCommand(SelfInstallCommand):
 You can add more packages using the <c1>self add</c1> command and remove them using \
 the <c1>self remove</c1> command.
 """
+
+    @property
+    def _with_synchronization(self) -> bool:
+        return True

src/poetry/console/commands/sync.py

@@ -34,3 +34,7 @@ class SyncCommand(InstallCommand):
 If you want to use Poetry only for dependency management but not for packaging,
 you can set the "package-mode" to false in your pyproject.toml file.
 """
+
+    @property
+    def _with_synchronization(self) -> bool:
+        return True

tests/console/commands/self/test_install.py

@@ -56,14 +56,9 @@ def test_self_install(
 
     tester.execute()
 
-    expected_output = """\
-Updating dependencies
-Resolving dependencies...
-
-Writing lock file
-"""
-
-    assert tester.io.fetch_output() == expected_output
+    output = tester.io.fetch_output()
+    assert output.startswith("Updating dependencies")
+    assert output.endswith("Writing lock file\n")
     assert tester.io.fetch_error() == ""
 
 

tests/console/commands/self/test_sync.py

@@ -6,13 +6,16 @@
 
 from cleo.exceptions import CleoNoSuchOptionError
 
+from poetry.console.commands.self.sync import SelfSyncCommand
+
 # import all tests from the self install command
 # and run them for sync by overriding the command fixture
 from tests.console.commands.self.test_install import *  # noqa: F403
 
 
 if TYPE_CHECKING:
     from cleo.testers.command_tester import CommandTester
+    from pytest_mock import MockerFixture
 
 
 @pytest.fixture  # type: ignore[no-redef]
@@ -28,3 +31,15 @@ def test_sync_deprecation() -> None:
 def test_sync_option_not_available(tester: CommandTester) -> None:
     with pytest.raises(CleoNoSuchOptionError):
         tester.execute("--sync")
+
+
+def test_synced_installer(tester: CommandTester, mocker: MockerFixture) -> None:
+    assert isinstance(tester.command, SelfSyncCommand)
+    mock = mocker.patch(
+        "poetry.console.commands.install.InstallCommand.installer",
+        new_callable=mocker.PropertyMock,
+    )
+
+    tester.execute()
+
+    mock.return_value.requires_synchronization.assert_called_with(True)

tests/console/commands/test_sync.py

@@ -6,13 +6,16 @@
 
 from cleo.exceptions import CleoNoSuchOptionError
 
+from poetry.console.commands.sync import SyncCommand
+
 # import all tests from the install command
 # and run them for sync by overriding the command fixture
 from tests.console.commands.test_install import *  # noqa: F403
 
 
 if TYPE_CHECKING:
     from cleo.testers.command_tester import CommandTester
+    from pytest_mock import MockerFixture
 
 
 @pytest.fixture  # type: ignore[no-redef]
@@ -28,3 +31,15 @@ def test_sync_option_is_passed_to_the_installer() -> None:
 def test_sync_option_not_available(tester: CommandTester) -> None:
     with pytest.raises(CleoNoSuchOptionError):
         tester.execute("--sync")
+
+
+def test_synced_installer(tester: CommandTester, mocker: MockerFixture) -> None:
+    assert isinstance(tester.command, SyncCommand)
+    mock = mocker.patch(
+        "poetry.console.commands.install.InstallCommand.installer",
+        new_callable=mocker.PropertyMock,
+    )
+
+    tester.execute()
+
+    mock.return_value.requires_synchronization.assert_called_with(True)