facilitate creating and installing WebExtensions during tests

It is now possible to more conveniently test WebExtension APIs code by wrapping it into a test WebExtension and temporarily installing in the driven browser.

2 files changed, 41 insertions, 7 deletions

diff --git a/test/unit/conftest.py b/test/unit/conftest.py
index 1500006..e1c98a1 100644
--- a/test/unit/conftest.py
+++ b/test/unit/conftest.py
@@ -26,10 +26,14 @@ Common fixtures for Haketilo unit tests
 # proprietary program, I am not going to enforce this in court.
 
 import pytest
+from pathlib import Path
+from selenium.webdriver.support.ui import WebDriverWait
+from selenium.webdriver.support import expected_conditions as EC
 
-from ..profiles      import firefox_safe_mode
-from ..server        import do_an_internet
-from ..script_loader import load_script
+from ..profiles           import firefox_safe_mode
+from ..server             import do_an_internet
+from ..script_loader      import load_script
+from ..extension_crafting import make_extension
 
 @pytest.fixture(scope="package")
 def proxy():
@@ -43,6 +47,23 @@ def driver(proxy):
         yield driver
         driver.quit()
 
+@pytest.fixture()
+def webextension(driver, request):
+    ext_data = request.node.get_closest_marker('ext_data')
+    if ext_data is None:
+        raise Exception('"webextension" fixture requires "ext_data" marker to be set')
+
+    ext_path = make_extension(Path(driver.firefox_profile.path),
+                              **ext_data.args[0])
+    driver.get('https://gotmyowndoma.in/')
+    addon_id = driver.install_addon(str(ext_path), temporary=True)
+    WebDriverWait(driver, 10).until(
+        EC.title_contains("Extension's options page for testing")
+    )
+    yield
+    driver.uninstall_addon(addon_id)
+    ext_path.unlink()
+
 script_injecting_script = '''\
 /*
  * Selenium by default executes scripts in some weird one-time context. We want
@@ -63,8 +84,8 @@ window.arguments = arguments[1];
 document.body.append(script_elem);
 
 /*
- * To ease debugging, we want this script to forward signal all exceptions from
- * the injectee.
+ * To ease debugging, we want this script to signal all exceptions from the
+ * injectee.
  */
 try {
     if (window.haketilo_selenium_exception !== false)
diff --git a/test/unit/test_basic.py b/test/unit/test_basic.py
index cbe5c8c..3b09cb6 100644
--- a/test/unit/test_basic.py
+++ b/test/unit/test_basic.py
@@ -26,8 +26,9 @@ def test_driver(driver):
     """
     for proto in ['http://', 'https://']:
         driver.get(proto + 'gotmyowndoma.in')
-        element = driver.find_element_by_tag_name('title')
-        title = driver.execute_script('return arguments[0].innerText;', element)
+        title = driver.execute_script(
+            'return document.getElementsByTagName("title")[0].innerText;'
+        )
         assert "Schrodinger's Document" in title
 
 def test_script_loader(execute_in_page, load_into_page):
@@ -39,3 +40,15 @@ def test_script_loader(execute_in_page, load_into_page):
                    page='https://gotmyowndoma.in')
 
     assert execute_in_page('returnval(TYPE_PREFIX.VAR);') == '_'
+
+@pytest.mark.ext_data({})
+def test_webextension(driver, webextension):
+    """
+    A trivial test case that verifies a test WebExtension created and installed
+    by the `webextension` fixture works and redirects specially-constructed URLs
+    to its test page.
+    """
+    heading = driver.execute_script(
+        'return document.getElementsByTagName("h1")[0].innerText;'
+    )
+    assert "Extension's options page for testing" in heading