1 files changed, 30 insertions, 0 deletions
diff --git a/lib/spack/spack/test/conftest.py b/lib/spack/spack/test/conftest.py
index 938dd402b7..186e8a8c27 100644
--- a/lib/spack/spack/test/conftest.py
+++ b/lib/spack/spack/test/conftest.py
@@ -656,6 +656,36 @@ def mock_store(tmpdir_factory, mock_repo_path, mock_configuration,
 
 
 @pytest.fixture(scope='function')
+def mutable_mock_store(tmpdir_factory, mock_repo_path, mock_configuration,
+                       _store_dir_and_cache):
+    """Creates a read-only mock database with some packages installed note
+    that the ref count for dyninst here will be 3, as it's recycled
+    across each install.
+
+    This does not actually activate the store for use by Spack -- see the
+    ``database`` fixture for that.
+
+    """
+    store_path, store_cache = _store_dir_and_cache
+    store = spack.store.Store(str(store_path))
+
+    # If the cache does not exist populate the store and create it
+    if not os.path.exists(str(store_cache.join('.spack-db'))):
+        with use_configuration(mock_configuration):
+            with use_store(store):
+                with use_repo(mock_repo_path):
+                    _populate(store.db)
+        store_path.copy(store_cache, mode=True, stat=True)
+
+    # Make the DB filesystem read-only to ensure we can't modify entries
+    store_path.join('.spack-db').chmod(mode=0o555, rec=1)
+
+    yield store
+
+    store_path.join('.spack-db').chmod(mode=0o755, rec=1)
+
+
+@pytest.fixture(scope='function')
 def database(mock_store, mock_packages, config, monkeypatch):
     """This activates the mock store, packages, AND config."""
     monkeypatch.setattr(spack.store, 'store', mock_store)