improve screenshot_regression types; add tests for pytest-splinter

Author: Apkawa

image_diff_reference/tests.test_splinter/test_splinter--reference.png

@@ -1,4 +1,4 @@
-from typing import BinaryIO, Union, Tuple, Callable, Optional
+from typing import BinaryIO, Union, Tuple, Optional
 
 from PIL.Image import Image
 from typing_extensions import Literal, Protocol
@@ -7,8 +7,6 @@
 ImageFileType = Union[Image, PathOrFileType]
 ImageSize = Tuple[int, int]
 
-ScreenshotRegressionCallableType = Callable[[float, Optional[str]], bool]
-
 
 class ImageRegressionCallableType(Protocol):
     def __call__(

image_diff_reference/tests.test_splinter/test_splinter-small_window-reference.png

@@ -1,15 +1,27 @@
+import pytest
 from tempfile import NamedTemporaryFile
-from typing import Optional
+from typing import Optional, Generator
+from typing_extensions import Protocol
 
-import pytest
 
 try:
     # Check pytest-splinter
     from pytest_splinter.plugin import Browser
 except ImportError:
     raise
 
-from ._types import ScreenshotRegressionCallableType, ImageRegressionCallableType
+from ._types import ImageRegressionCallableType
+
+
+class ScreenshotRegressionCallableType(Protocol):
+    def __call__(
+        self,
+        browser: Optional[Browser] = None,
+        threshold: Optional[float] = None,
+        suffix: Optional[str] = None,
+    ) -> bool:
+        pass
+
 
 __all__ = ["screenshot_regression"]
 
@@ -19,19 +31,29 @@ def screenshot_regression(
     browser: Browser,
     image_regression: ImageRegressionCallableType,
     image_diff_threshold: float,
-) -> ScreenshotRegressionCallableType:
+) -> Generator[ScreenshotRegressionCallableType, None, None]:
     """
     Check regression browser screenshot
+
+    :param browser: optional, by default from `browser` fixture
     :param threshold: float, by default from `image_diff_threshold`
     :param suffix: str, need for multiple checks  by one test
     """
+    default_browser = browser
 
     def _factory(
-        threshold: float = image_diff_threshold, suffix: Optional[str] = ""
+        browser: Optional[Browser] = None,
+        threshold: Optional[float] = None,
+        suffix: Optional[str] = "",
     ) -> bool:
+        if browser is None:
+            browser = default_browser
+
+        if threshold is None:
+            threshold = image_diff_threshold
         tf = NamedTemporaryFile(suffix=".png")
         image = tf.name
         browser.driver.save_screenshot(image)
         return image_regression(image, threshold, suffix)
 
-    return _factory
+    yield _factory

pytest_image_diff/_types.py

@@ -1,4 +1,5 @@
 import os
+
 import pytest
 
 try:
@@ -35,3 +36,15 @@ def splinter_webdriver_executable(request, splinter_webdriver):
 @with_splinter
 def test_splinter_fixture(screenshot_regression):
     assert screenshot_regression
+
+
+HTML_FILE = os.path.join(os.path.dirname(__file__), "files/example.html")
+
+
+@with_splinter
+def test_splinter(browser, screenshot_regression):
+    browser.driver.set_window_size(1280, 1024)
+    browser.visit("file://" + HTML_FILE)
+    screenshot_regression()
+    browser.driver.set_window_size(800, 600)
+    screenshot_regression(suffix="small_window")