test: remove and replace redundant tests of internals (#307)

Author: mcous

pyproject.toml

@@ -83,6 +83,7 @@ test-ci = ["test-once", "coverage-xml"]
 [tool.pytest.ini_options]
 addopts = "--color=yes --mypy-ini-file=tests/typing/mypy.ini --mypy-only-local-stub"
 asyncio_mode = "auto"
+filterwarnings = ["error::decoy.warnings.DecoyWarning"]
 
 [tool.mypy]
 files = ["decoy", "tests"]

tests/fixtures.py

@@ -1,7 +1,7 @@
 """Common test fixtures."""
 
 from functools import lru_cache
-from typing import Any, Generic, TypeVar, Optional, Union
+from typing import Any, Generic, Optional, TypeVar, Union
 
 
 class SomeClass:
@@ -114,7 +114,6 @@ async def __call__(self, val: int) -> int:
 
 def noop(*args: Any, **kwargs: Any) -> Any:
     """No-op."""
-    raise NotImplementedError()
 
 
 def some_func(val: str) -> str:

tests/test_errors.py

@@ -6,19 +6,28 @@
 
 from decoy import Decoy, errors
 from decoy.spy import AsyncSpy, Spy
+from decoy.warnings import IncorrectCallWarning
 
 from .fixtures import SomeClass, some_func
 
 
-def test_decoy_creates_spy(decoy: Decoy) -> None:
-    """It should be able to create a Spy from a class."""
+def test_create_mock(decoy: Decoy) -> None:
+    """It creates a mock from a class."""
     subject = decoy.mock(cls=SomeClass)
 
     assert isinstance(subject, SomeClass)
     assert isinstance(subject, Spy)
     assert repr(subject) == "<Decoy mock `tests.fixtures.SomeClass`>"
 
 
+def test_method_noop(decoy: Decoy) -> None:
+    """A method mock no-ops by default."""
+    subject = decoy.mock(cls=SomeClass)
+    result = subject.foo("hello")
+
+    assert result is None
+
+
 def test_decoy_creates_func_spy(decoy: Decoy) -> None:
     """It should be able to create a Spy from a function."""
     subject = decoy.mock(func=some_func)
@@ -28,6 +37,22 @@ def test_decoy_creates_func_spy(decoy: Decoy) -> None:
     assert repr(subject) == "<Decoy mock `tests.fixtures.some_func`>"
 
 
+def test_func_noop(decoy: Decoy) -> None:
+    """A function mock no-ops by default."""
+    subject = decoy.mock(func=some_func)
+    result = subject("hello")
+
+    assert result is None
+
+
+def test_func_bad_call(decoy: Decoy) -> None:
+    """It raises an IncorrectCallWarning if call is bad."""
+    subject = decoy.mock(func=some_func)
+
+    with pytest.warns(IncorrectCallWarning):
+        subject("hello", "world")  # type: ignore[call-arg]
+
+
 def test_decoy_creates_specless_spy(decoy: Decoy) -> None:
     """It should be able to create a spec-less spy."""
     subject = decoy.mock(name="subject")

tests/test_mock.py

@@ -0,0 +1,24 @@
+"""Tests for decoy.prop."""
+
+import pytest
+
+from decoy import Decoy
+from decoy.errors import MissingRehearsalError
+
+from .fixtures import SomeClass
+
+
+def test_property_missing_rehearsal(decoy: Decoy) -> None:
+    """It raises an error if no prop rehearsal."""
+    with pytest.raises(MissingRehearsalError):
+        decoy.prop("42")
+
+
+def test_property_missing_rehearsal_after_success(decoy: Decoy) -> None:
+    """It raises an error if no prop rehearsal after a successful rehearsal."""
+    subject = decoy.mock(cls=SomeClass)
+
+    decoy.prop(subject.primitive_property)
+
+    with pytest.raises(MissingRehearsalError):
+        decoy.prop("42")