diff --git a/poetry.lock b/poetry.lock
index a8196cb1e..6f0523a42 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -2453,23 +2453,6 @@ Werkzeug = "*"
 [package.extras]
 docs = ["Sphinx", "sphinx-rtd-theme"]
 
-[[package]]
-name = "pytest-mock"
-version = "3.15.1"
-description = "Thin-wrapper around the mock package for easier use with pytest"
-optional = false
-python-versions = ">=3.9"
-files = [
-    {file = "pytest_mock-3.15.1-py3-none-any.whl", hash = "sha256:0a25e2eb88fe5168d535041d09a4529a188176ae608a6d249ee65abc0949630d"},
-    {file = "pytest_mock-3.15.1.tar.gz", hash = "sha256:1849a238f6f396da19762269de72cb1814ab44416fa73a8686deac10b0d87a0f"},
-]
-
-[package.dependencies]
-pytest = ">=6.2.5"
-
-[package.extras]
-dev = ["pre-commit", "pytest-asyncio", "tox"]
-
 [[package]]
 name = "python-dateutil"
 version = "2.9.0.post0"
@@ -3689,4 +3672,4 @@ web = ["flask", "flask-cors"]
 [metadata]
 lock-version = "2.0"
 python-versions = ">=3.9,<4"
-content-hash = "8ed50b90e399bace64062c38f784f9c7bcab2c2b7c0728cfe0a9ee78ea1fd902"
+content-hash = "1db39186aca430ef6f1fd9e51b9dcc3ed91880a458bc21b22d950ed8589fdf5a"
diff --git a/pyproject.toml b/pyproject.toml
index 5eb82f6c7..0058c7f9b 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -100,7 +100,6 @@ rarfile = "*"
 requests-mock = ">=1.12.1"
 requests_oauthlib = "*"
 responses = ">=0.3.0"
-pytest-mock = "^3.15.1"
 
 [tool.poetry.group.lint.dependencies]
 docstrfmt = ">=1.11.1"
diff --git a/test/plugins/test_lastgenre.py b/test/plugins/test_lastgenre.py
index 91dd7c282..151f122a6 100644
--- a/test/plugins/test_lastgenre.py
+++ b/test/plugins/test_lastgenre.py
@@ -14,16 +14,18 @@
 
 """Tests for the 'lastgenre' plugin."""
 
-from unittest.mock import Mock
+from unittest.mock import Mock, patch
 
 import pytest
 
 from beets.test import _common
-from beets.test.helper import BeetsTestCase
+from beets.test.helper import PluginTestCase
 from beetsplug import lastgenre
 
 
-class LastGenrePluginTest(BeetsTestCase):
+class LastGenrePluginTest(PluginTestCase):
+    plugin = "lastgenre"
+
     def setUp(self):
         super().setUp()
         self.plugin = lastgenre.LastGenrePlugin()
@@ -131,6 +133,36 @@ class LastGenrePluginTest(BeetsTestCase):
             "math rock",
         ]
 
+    @patch("beets.ui.should_write", Mock(return_value=True))
+    @patch(
+        "beetsplug.lastgenre.LastGenrePlugin._get_genre",
+        Mock(return_value=("Mock Genre", "mock stage")),
+    )
+    def test_pretend_option_skips_library_updates(self):
+        item = self.create_item(
+            album="Pretend Album",
+            albumartist="Pretend Artist",
+            artist="Pretend Artist",
+            title="Pretend Track",
+            genre="Original Genre",
+        )
+        album = self.lib.add_album([item])
+
+        def unexpected_store(*_, **__):
+            raise AssertionError("Unexpected store call")
+
+        # Verify that try_write was never called (file operations skipped)
+        with (
+            patch("beetsplug.lastgenre.Item.store", unexpected_store),
+            self.assertLogs() as logs,
+        ):
+            self.run_command("lastgenre", "--pretend")
+
+        assert "Mock Genre" in str(logs.output)
+        album.load()
+        assert album.genre == "Original Genre"
+        assert album.items()[0].genre == "Original Genre"
+
     def test_no_duplicate(self):
         """Remove duplicated genres."""
         self._setup_config(count=99)
@@ -172,52 +204,6 @@ class LastGenrePluginTest(BeetsTestCase):
         assert res == ["ambient", "electronic"]
 
 
-def test_pretend_option_skips_library_updates(mocker):
-    """Test that pretend mode logs actions but skips library updates."""
-
-    # Setup
-    test_case = BeetsTestCase()
-    test_case.setUp()
-    plugin = lastgenre.LastGenrePlugin()
-    item = test_case.create_item(
-        album="Album",
-        albumartist="Artist",
-        artist="Artist",
-        title="Track",
-        genre="Original Genre",
-    )
-    album = test_case.lib.add_album([item])
-    command = plugin.commands()[0]
-    opts, args = command.parser.parse_args(["--pretend"])
-
-    # Mocks
-    mocker.patch.object(lastgenre.ui, "should_write", return_value=True)
-    mock_get_genre = mocker.patch.object(
-        plugin, "_get_genre", return_value=("New Genre", "log label")
-    )
-    mock_log = mocker.patch.object(plugin._log, "info")
-    mock_write = mocker.patch.object(item, "try_write")
-
-    # Run lastgenre
-    command.func(test_case.lib, opts, args)
-    mock_get_genre.assert_called_once()
-
-    # Test logging
-    assert any(
-        call.args[0].startswith("Pretend:") for call in mock_log.call_args_list
-    )
-
-    # Test file operations should be skipped
-    mock_write.assert_not_called()
-
-    # Test database should remain unchanged
-    stored_album = test_case.lib.get_album(album.id)
-    assert stored_album.genre == "Original Genre"
-    assert stored_album.items()[0].genre == "Original Genre"
-
-    test_case.tearDown()
-
-
 @pytest.mark.parametrize(
     "config_values, item_genre, mock_genres, expected_result",
     [