diff --git a/tests/tools_test.py b/tests/tools_test.py
index ee76f1c..60a5a4a 100644
--- a/tests/tools_test.py
+++ b/tests/tools_test.py
@@ -1,31 +1,79 @@
-
-
 from corrlib import tools as tl
+from configparser import ConfigParser
+import os
 
 
-def test_m2k():
+def test_m2k() -> None:
     for m in [0.1, 0.5, 1.0]:
         expected_k = 1 / (2 * m + 8)
         assert tl.m2k(m) == expected_k
 
 
-def test_k2m():
+def test_k2m() -> None:
     for m in [0.1, 0.5, 1.0]:
         assert tl.k2m(m) == (1/(2*m))-4
 
 
-def test_k2m_m2k():
+def test_k2m_m2k() -> None:
     for m in [0.1, 0.5, 1.0]:
         k = tl.m2k(m)
         m_converted = tl.k2m(k)
         assert abs(m - m_converted) < 1e-9
 
 
-def test_str2list():
+def test_str2list() -> None:
     assert tl.str2list("a,b,c") == ["a", "b", "c"]
     assert tl.str2list("1,2,3") == ["1", "2", "3"]
 
 
-def test_list2str():
+def test_list2str() -> None:
     assert tl.list2str(["a", "b", "c"]) == "a,b,c"
     assert tl.list2str(["1", "2", "3"]) == "1,2,3"
+
+
+def test_set_config(tmp_path: str) -> None:
+    section = "core"
+    option = "test_option"
+    value = "test_value"
+    # config is not yet available
+    tl.set_config(tmp_path, section, option, value)
+    config_path = os.path.join(tmp_path, '.corrlib')
+    config = ConfigParser()
+    config.read(config_path)
+    assert config.get('core', 'test_option', fallback="not the value") == "test_value"
+    # now, a config file is already present
+    section = "core"
+    option = "test_option2"
+    value = "test_value2"
+    tl.set_config(tmp_path, section, option, value)
+    config_path = os.path.join(tmp_path, '.corrlib')
+    config = ConfigParser()
+    config.read(config_path)
+    assert config.get('core', 'test_option2', fallback="not the value") == "test_value2"
+    # update option 2
+    section = "core"
+    option = "test_option2"
+    value = "test_value3"
+    tl.set_config(tmp_path, section, option, value)
+    config_path = os.path.join(tmp_path, '.corrlib')
+    config = ConfigParser()
+    config.read(config_path)
+    assert config.get('core', 'test_option2', fallback="not the value") == "test_value3"
+
+
+def test_get_db_file(tmp_path: str) -> None:
+    section = "paths"
+    option = "db"
+    value = "test_value"
+    # config is not yet available
+    tl.set_config(tmp_path, section, option, value)
+    assert tl.get_db_file(tmp_path) == "test_value"
+
+
+def test_cache_enabled(tmp_path: str) -> None:
+    section = "core"
+    option = "cached"
+    value = "True"
+    # config is not yet available
+    tl.set_config(tmp_path, section, option, value)
+    assert tl.get_db_file(tmp_path)