Unify all config parameter types

tests/test_config.py

-"""
-Test config options.
-"""
+"""Test config options."""
 import logging
 from unittest.mock import patch
 
+import pytest
+
+from theano import configparser
 from theano.configdefaults import default_blas_ldflags
 from theano.configparser import THEANO_FLAGS_DICT, AddConfigVar, ConfigParam
 
@@ -12,24 +13,23 @@ def test_invalid_default():
     # Ensure an invalid default value found in the Theano code only causes
     # a crash if it is not overridden by the user.
 
-    def filter(val):
+    def validate(val):
         if val == "invalid":
-            raise ValueError()
-        else:
-            return val
+            raise ValueError("Test-triggered")
 
-    try:
+    with pytest.raises(ValueError, match="Test-triggered"):
         # This should raise a ValueError because the default value is
         # invalid.
         AddConfigVar(
             "T_config.test_invalid_default_a",
             doc="unittest",
-            configparam=ConfigParam("invalid", filter=filter),
+            configparam=ConfigParam("invalid", validate=validate),
             in_c_key=False,
         )
-        raise AssertionError()
-    except ValueError:
-        pass
+
+    THEANO_FLAGS_DICT["T_config.test_invalid_default_b"] = "ok"
+    # This should succeed since we defined a proper value, even
+    # though the default was invalid.
 
     THEANO_FLAGS_DICT["T_config.test_invalid_default_b"] = "ok"
     # This should succeed since we defined a proper value, even
@@ -37,15 +37,14 @@ def test_invalid_default():
     AddConfigVar(
         "T_config.test_invalid_default_b",
         doc="unittest",
-        configparam=ConfigParam("invalid", filter=filter),
+        configparam=ConfigParam("invalid", validate=validate),
         in_c_key=False,
     )
 
+    # TODO We should remove these dummy options on test exit.
     # Check that the flag has been removed
     assert "T_config.test_invalid_default_b" not in THEANO_FLAGS_DICT
 
-    # TODO We should remove these dummy options on test exit.
-
 
 @patch("theano.configdefaults.try_blas_flag", return_value=None)
 @patch("theano.configdefaults.sys")
@@ -58,3 +57,50 @@ def test_default_blas_ldflags(sys_mock, try_blas_flag_mock, caplog):
             default_blas_ldflags()
 
     assert "install mkl with" in caplog.text
+
+
+def test_config_param_apply_and_validation():
+    cp = ConfigParam(
+        "TheDeFauLt",
+        apply=lambda v: v.lower(),
+        validate=lambda v: v in "thedefault,thesetting",
+        mutable=True,
+    )
+    assert cp.default == "TheDeFauLt"
+    assert not hasattr(cp, "val")
+
+    # can't assign invalid value
+    with pytest.raises(ValueError, match="Invalid value"):
+        cp.__set__("cls", "invalid")
+
+    assert not hasattr(cp, "val")
+
+    # effectivity of apply function
+    cp.__set__("cls", "THESETTING")
+    assert cp.val == "thesetting"
+
+    # respect the mutability
+    cp._mutable = False
+    with pytest.raises(Exception, match="Can't change"):
+        cp.__set__("cls", "THEDEFAULT")
+
+
+def test_config_types_bool():
+    valids = {
+        True: ["1", 1, True, "true", "True"],
+        False: ["0", 0, False, "false", "False"],
+    }
+
+    param = configparser.BoolParam(None)
+
+    assert isinstance(param, configparser.ConfigParam)
+    assert param.default is None
+
+    for outcome, inputs in valids.items():
+        for input in inputs:
+            applied = param.apply(input)
+            assert applied == outcome
+            assert param.validate(applied) is not False
+
+    with pytest.raises(ValueError, match="Invalid value"):
+        param.apply("notabool")