feat: add --project flag to ape test command

src/ape/managers/project.py

@@ -1,4 +1,5 @@
 import json
+import os
 import random
 import shutil
 from collections.abc import Callable, Iterable, Iterator
@@ -2568,6 +2569,36 @@ def clean(self):
         self.sources._path_cache = None
         self._clear_cached_config()
 
+    def chdir(self, path: Path):
+        """
+        Change the local project to the new path.
+
+        Args:
+            path (Path): The path of the new project.
+        """
+        if self.path == path:
+            return  # Already there!
+
+        os.chdir(path)
+
+        # Clear cached properties.
+        for prop in (
+            "path",
+            "_deduced_contracts_folder",
+            "project_api",
+            "contracts",
+            "interfaces_folder",
+            "sources",
+        ):
+            self.__dict__.pop(prop, None)
+
+        # Re-initialize
+        self._session_source_change_check = set()
+        self._config_override = {}
+        self._base_path = Path(path).resolve()
+        self.manifest_path = self._base_path / ".build" / "__local__.json"
+        self._manifest = self.load_manifest()
+
     def reload_config(self):
         """
         Reload the local ape-config.yaml file.

src/ape/pytest/plugin.py

@@ -47,6 +47,7 @@ def add_option(*names, **kwargs):
         help="A comma-separated list of contract:method-name glob-patterns to ignore.",
     )
     add_option("--coverage", action="store_true", help="Collect contract coverage.")
+    add_option("--project", action="store", help="Change Ape's project")
 
     # NOTE: Other pytest plugins, such as hypothesis, should integrate with pytest separately
 
@@ -79,6 +80,9 @@ def is_module(v):
     from ape.pytest.runners import PytestApeRunner
     from ape.utils.basemodel import ManagerAccessMixin
 
+    if project := config.getoption("--project"):
+        ManagerAccessMixin.local_project.chdir(project)
+
     # Register the custom Ape test runner
     config_wrapper = ConfigWrapper(config)
     receipt_capture = ReceiptCapture(config_wrapper)

tests/functional/test_project.py

@@ -1053,3 +1053,14 @@ def test_instance_map(self, project, vyper_contract_instance, mock_sepolia):
                 return
 
         assert False, "Failed to find expected URI"
+
+
+def test_chdir(project):
+    original_path = project.path
+    with create_tempdir() as new_path:
+        project.chdir(new_path)
+        assert project.path == new_path
+
+    # Undo.
+    project.chdir(original_path)
+    assert project.path == original_path

tests/integration/cli/test_test.py

@@ -442,3 +442,28 @@ def test_watch(mocker, integ_project, runner, ape_cli):
     assert result.exit_code == 0
 
     runner_patch.assert_called_once_with((Path("contracts"), Path("tests")), 0.5, "-s")
+
+
+@skip_projects_except("with-contracts")
+def test_project_option(integ_project, ape_cli, runner):
+    _ = integ_project  # NOTE: Not actually used, but avoid running across all projects.
+
+    # NOTE: Using isolated filesystem so that
+    with runner.isolated_filesystem():
+        # Setup a project
+        project_name = "test-token-project"
+        project_dir = Path.cwd() / project_name
+        tests_dir = project_dir / "tests"
+        tests_dir.mkdir(parents=True)
+
+        # Setup a test
+        test_file = tests_dir / "test_project_option.py"
+        test_text = """
+def test_project_option():
+    assert True
+""".lstrip()
+        test_file.write_text(test_text)
+
+        result = runner.invoke(ape_cli, ("test", "--project", f"./{project_name}"))
+        assert "1 passed" in result.output
+        assert result.exit_code == 0