add support for callable default

ragdoll/base.py

@@ -33,9 +33,15 @@ def __init__(
 
     @property
     def _default(self) -> Any:
+        if callable(self._default_value):
+            value = self._default_value()
+        else:
+            value = self._default_value
+
         if self._process_default_value:
-            return self.to_python(self._default_value)
-        return self._default_value
+            return self.to_python(value)
+
+        return value
 
     @property
     def name(self):

tests/test_env/test_bool_env.py

@@ -51,3 +51,10 @@ class MyEnvSetting(EnvSetting):
         FOO = BoolEnv(False)
 
     assert MyEnvSetting.__dict__["FOO"].name == "FOO"
+
+
+def test_bool_env_callable_default():
+    class MyEnvSetting(EnvSetting):
+        FOO = BoolEnv(lambda: False)
+
+    assert MyEnvSetting.FOO is False

tests/test_env/test_int_env.py

@@ -49,3 +49,10 @@ def test_process_default_value_choices_error():
 
         class MyEnvSetting(EnvSetting):
             FOO = IntEnv("0", process_default_value=True, choices=[1])
+
+
+def test_int_env_callable_default():
+    class MyEnvSetting(EnvSetting):
+        FOO = IntEnv(lambda: 300)
+
+    assert MyEnvSetting.FOO == 300

tests/test_env/test_str_env.py

@@ -49,3 +49,10 @@ class MyEnvSetting(EnvSetting):
         FOO = StrEnv("")
 
     assert MyEnvSetting.__dict__["FOO"].name == "FOO"
+
+
+def test_str_env_callable_default():
+    class MyEnvSetting(EnvSetting):
+        FOO = StrEnv(lambda: "")
+
+    assert MyEnvSetting.FOO == ""