fix: do not print unwanted operations on --lock (#7915)

Co-authored-by: Randy Döring <30527984+radoering@users.noreply.github.com>

src/poetry/installation/executor.py

@@ -108,6 +108,10 @@ class Executor:
     def removals_count(self) -> int:
         return self._executed["uninstall"]
 
+    @property
+    def enabled(self) -> bool:
+        return self._enabled
+
     def supports_fancy_output(self) -> bool:
         return self._io.output.is_decorated() and not self._dry_run
 

src/poetry/installation/installer.py

@@ -53,7 +53,6 @@ class Installer:
         self._requires_synchronization = False
         self._update = False
         self._verbose = False
-        self._write_lock = True
         self._groups: Iterable[str] | None = None
         self._skip_directory = False
         self._lock = False
@@ -99,7 +98,6 @@ class Installer:
 
         if self.is_dry_run():
             self.verbose(True)
-            self._write_lock = False
 
         return self._do_install()
 
@@ -269,7 +267,7 @@ class Installer:
         lockfile_repo = LockfileRepository()
         self._populate_lockfile_repo(lockfile_repo, ops)
 
-        if self._lock and self._update:
+        if not self.executor.enabled:
             # If we are only in lock mode, no need to go any further
             self._write_lock_file(lockfile_repo)
             return 0
@@ -348,7 +346,7 @@ class Installer:
         return status
 
     def _write_lock_file(self, repo: LockfileRepository, force: bool = False) -> None:
-        if self._write_lock and (force or self._update):
+        if not self.is_dry_run() and (force or self._update):
             updated_lock = self._locker.set_lock_data(self._package, repo.packages)
 
             if updated_lock:

tests/console/commands/test_update.py

@@ -16,7 +16,7 @@ if TYPE_CHECKING:
 
 
 @pytest.fixture
-def poetry_with_up_to_date_lockfile(
+def poetry_with_outdated_lockfile(
     project_factory: ProjectFactory, fixture_dir: FixtureDirGetter
 ) -> Poetry:
     source = fixture_dir("outdated_lock")
@@ -37,21 +37,46 @@ def poetry_with_up_to_date_lockfile(
 )
 def test_update_with_dry_run_keep_files_intact(
     command: str,
-    poetry_with_up_to_date_lockfile: Poetry,
+    poetry_with_outdated_lockfile: Poetry,
     repo: TestRepository,
     command_tester_factory: CommandTesterFactory,
 ) -> None:
-    tester = command_tester_factory("update", poetry=poetry_with_up_to_date_lockfile)
+    tester = command_tester_factory("update", poetry=poetry_with_outdated_lockfile)
 
-    original_pyproject_content = poetry_with_up_to_date_lockfile.file.read()
-    original_lockfile_content = poetry_with_up_to_date_lockfile._locker.lock_data
+    original_pyproject_content = poetry_with_outdated_lockfile.file.read()
+    original_lockfile_content = poetry_with_outdated_lockfile._locker.lock_data
 
     repo.add_package(get_package("docker", "4.3.0"))
     repo.add_package(get_package("docker", "4.3.1"))
 
     tester.execute(command)
 
-    assert poetry_with_up_to_date_lockfile.file.read() == original_pyproject_content
-    assert (
-        poetry_with_up_to_date_lockfile._locker.lock_data == original_lockfile_content
-    )
+    assert poetry_with_outdated_lockfile.file.read() == original_pyproject_content
+    assert poetry_with_outdated_lockfile._locker.lock_data == original_lockfile_content
+
+
+@pytest.mark.parametrize(
+    ("command", "expected"),
+    [
+        ("", True),
+        ("--dry-run", True),
+        ("--lock", False),
+    ],
+)
+def test_update_prints_operations(
+    command: str,
+    expected: bool,
+    poetry_with_outdated_lockfile: Poetry,
+    repo: TestRepository,
+    command_tester_factory: CommandTesterFactory,
+) -> None:
+    tester = command_tester_factory("update", poetry=poetry_with_outdated_lockfile)
+
+    repo.add_package(get_package("docker", "4.3.0"))
+    repo.add_package(get_package("docker", "4.3.1"))
+
+    tester.execute(command)
+    output = tester.io.fetch_output()
+
+    assert ("Package operations:" in output) is expected
+    assert ("Installing docker (4.3.1)" in output) is expected