test: add test for extension testing (microsoft#695)

Author: mxschmitt

playwright/_impl/_browser_context.py

@@ -69,7 +69,6 @@ def __init__(
         self._timeout_settings = TimeoutSettings(None)
         self._browser: Optional["Browser"] = None
         self._owner_page: Optional[Page] = None
-        self._is_closed_or_closing = False
         self._options: Dict[str, Any] = {}
         self._background_pages: Set[Page] = set()
         self._service_workers: Set[Worker] = set()
@@ -129,6 +128,8 @@ def __init__(
                 from_nullable_channel(params.get("page")),
             ),
         )
+        self._closed_future: asyncio.Future = asyncio.Future()
+        self.once(self.Events.Close, lambda: self._closed_future.set_result(True))
 
     def __repr__(self) -> str:
         return f"<BrowserContext browser={self.browser}>"
@@ -278,18 +279,15 @@ def expect_event(
         return EventContextManagerImpl(wait_helper.result())
 
     def _on_close(self) -> None:
-        self._is_closed_or_closing = True
         if self._browser:
             self._browser._contexts.remove(self)
 
         self.emit(BrowserContext.Events.Close)
 
     async def close(self) -> None:
-        if self._is_closed_or_closing:
-            return
-        self._is_closed_or_closing = True
         try:
             await self._channel.send("close")
+            await self._closed_future
         except Exception as e:
             if not is_safe_close_error(e):
                 raise e

tests/assets/simple-extension/content-script.js

@@ -0,0 +1,2 @@
+console.log('hey from the content-script');
+self.thisIsTheContentScript = true;

tests/assets/simple-extension/index.js

@@ -0,0 +1,2 @@
+// Mock script for background extension
+window.MAGIC = 42;

tests/assets/simple-extension/manifest.json

@@ -0,0 +1,14 @@
+{
+  "name": "Simple extension",
+  "version": "0.1",
+  "background": {
+    "scripts": ["index.js"]
+  },
+  "content_scripts": [{
+    "matches": ["<all_urls>"],
+    "css": [],
+    "js": ["content-script.js"]
+  }],
+  "permissions": ["background", "activeTab"],
+  "manifest_version": 2
+}

tests/async/test_launcher.py

@@ -47,7 +47,7 @@ async def test_browser_type_launch_should_reject_if_launched_browser_fails_immed
     with pytest.raises(Error):
         await browser_type.launch(
             **launch_arguments,
-            executable_path=assetdir / "dummy_bad_browser_executable.js"
+            executable_path=assetdir / "dummy_bad_browser_executable.js",
         )
 
 
@@ -109,3 +109,40 @@ async def test_browser_launch_non_existing_executable_path_shows_install_msg(
     with pytest.raises(Error) as exc_info:
         await browser_type.launch(executable_path=tmpdir.join("executable"))
     assert "python -m playwright install" in exc_info.value.message
+
+
+@pytest.mark.only_browser("chromium")
+async def test_browser_launch_should_return_background_pages(
+    browser_type: BrowserType,
+    tmpdir,
+    browser_channel,
+    assetdir,
+    launch_arguments,
+):
+    if browser_channel:
+        pytest.skip()
+
+    extension_path = str(assetdir / "simple-extension")
+    context = await browser_type.launch_persistent_context(
+        str(tmpdir),
+        **{
+            **launch_arguments,
+            "headless": False,
+            "args": [
+                f"--disable-extensions-except={extension_path}",
+                f"--load-extension={extension_path}",
+            ],
+        },  # type: ignore
+    )
+    background_page = None
+    if len(context.background_pages):
+        background_page = context.background_pages[0]
+    else:
+        background_page = await context.wait_for_event("backgroundpage")
+    assert background_page
+    assert background_page in context.background_pages
+    assert background_page not in context.pages
+    assert await background_page.evaluate("window.MAGIC") == 42
+    await context.close()
+    assert len(context.background_pages) == 0
+    assert len(context.pages) == 0