Merge pull request #4141 from askerry/selenium_display_image

Migrate image display test to selenium

Author: takluyver

notebook/tests/notebook/display_image.js

@@ -0,0 +1,65 @@
+"""Test display of images
+
+The effect of shape metadata is validated, using Image(retina=True)
+"""
+
+from .utils import wait_for_tag
+
+
+# 2x2 black square in b64 jpeg and png
+b64_image_data = {
+    "image/png" : b'iVBORw0KGgoAAAANSUhEUgAAAAIAAAACCAIAAAD91JpzAAAAC0lEQVR4nGNgQAYAAA4AAamRc7EA\\nAAAASUVORK5CYII',
+    "image/jpeg" : b'/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAAgGBgcGBQgHBwcJCQgKDBQNDAsLDBkSEw8UHRofHh0a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\noAoo2Qoo'
+}
+
+
+def imports(notebook):
+    commands = [
+        'import base64',
+        'from IPython.display import display, Image',
+    ]
+    notebook.edit_cell(index=0, content="\n".join(commands))
+    notebook.execute_cell(0)
+
+
+def validate_img(notebook, cell_index, image_fmt, retina):
+    """Validate that image renders as expected."""
+
+    b64data = b64_image_data[image_fmt]
+    commands = [
+        'b64data = %s' % b64data,
+        'data = base64.decodebytes(b64data)',
+        'display(Image(data, retina=%s))' % retina
+    ]
+    notebook.append("\n".join(commands))
+    notebook.execute_cell(cell_index)
+
+    # Find the image element that was just displayed
+    wait_for_tag(notebook.cells[cell_index], "img", single=True)
+    img_element = notebook.cells[cell_index].find_element_by_tag_name("img")
+
+    src = img_element.get_attribute("src")
+    prefix = src.split(',')[0]
+    expected_prefix = "data:%s;base64" % image_fmt
+    assert prefix == expected_prefix
+
+    expected_size = 1 if retina else 2
+    assert img_element.size["width"] == expected_size
+    assert img_element.size["height"] == expected_size
+    assert img_element.get_attribute("width") == str(expected_size)
+    assert img_element.get_attribute("height") == str(expected_size)
+
+
+def test_display_image(notebook):
+    imports(notebook)
+    # PNG, non-retina
+    validate_img(notebook, 1, "image/png", False)
+
+    # PNG, retina display
+    validate_img(notebook, 2, "image/png", True)
+
+    # JPEG, non-retina
+    validate_img(notebook, 3, "image/jpeg", False)
+
+    # JPEG, retina display
+    validate_img(notebook, 4, "image/jpeg", True)

notebook/tests/selenium/test_display_image.py

@@ -12,8 +12,14 @@
 pjoin = os.path.join
 
 
-def wait_for_selector(browser, selector, timeout=10, visible=False, single=False):
-    wait = WebDriverWait(browser, timeout)
+def wait_for_selector(driver, selector, timeout=10, visible=False, single=False):
+    return _wait_for(driver, By.CSS_SELECTOR, selector, timeout, visible, single)
+
+def wait_for_tag(driver, tag, timeout=10, visible=False, single=False):
+    return _wait_for(driver, By.TAG_NAME, tag, timeout, visible, single)
+
+def _wait_for(driver, locator_type, locator, timeout=10, visible=False, single=False):
+    wait = WebDriverWait(driver, timeout)
     if single:
         if visible:
             conditional = EC.visibility_of_element_located
@@ -24,7 +30,7 @@ def wait_for_selector(browser, selector, timeout=10, visible=False, single=False
             conditional = EC.visibility_of_all_elements_located
         else:
             conditional = EC.presence_of_all_elements_located
-    return wait.until(conditional((By.CSS_SELECTOR, selector)))
+    return wait.until(conditional((locator_type, locator)))
 
 
 class CellTypeError(ValueError):