4 files changed, 226 insertions, 0 deletions
diff --git a/tests/pyodide_testrunner/.gitignore b/tests/pyodide_testrunner/.gitignore
new file mode 100644
index 0000000..704d307
--- /dev/null
+++ b/tests/pyodide_testrunner/.gitignore
@@ -0,0 +1 @@
+*.whl
diff --git a/tests/pyodide_testrunner/index.html b/tests/pyodide_testrunner/index.html
new file mode 100644
index 0000000..b3e1b8b
--- /dev/null
+++ b/tests/pyodide_testrunner/index.html
@@ -0,0 +1,56 @@
+<!DOCTYPE html>
+<html lang="en">
+
+<head>
+    <meta charset="UTF-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+
+    <title>Pygls Testsuite</title>
+
+    <style>
+        @media (prefers-color-scheme: dark) {
+            * {
+                background-color: #222;
+                color: white;
+            }
+
+        }
+    </style>
+</head>
+
+<body>
+    <div>
+        <pre id="console"></pre>
+    </div>
+    <button id="exit-code" disabled></button>
+    <script>
+        let log = document.getElementById("console")
+        let exitCode = document.getElementById("exit-code")
+
+        function print(event) {
+            log.innerText += event.data
+        }
+
+        // Use a web worker to prevent freezing the UI
+        function runTests(whl) {
+            let worker = new Worker(`test-runner.js?whl=${whl}`)
+            worker.addEventListener('message', (event) => {
+
+                if (event.data.exitCode !== undefined) {
+                    exitCode.innerText = event.data.exitCode
+                    exitCode.disabled = false
+                    return
+                }
+
+                print(event)
+            })
+        }
+
+        let queryParams = new URLSearchParams(window.location.search)
+        runTests(queryParams.get('whl'))
+
+    </script>
+</body>
+
+</html>
diff --git a/tests/pyodide_testrunner/run.py b/tests/pyodide_testrunner/run.py
new file mode 100644
index 0000000..7b56374
--- /dev/null
+++ b/tests/pyodide_testrunner/run.py
@@ -0,0 +1,131 @@
+import os
+import pathlib
+import shutil
+import subprocess
+import sys
+import tempfile
+
+from functools import partial
+from http.server import SimpleHTTPRequestHandler, ThreadingHTTPServer
+from multiprocessing import Process, Queue
+
+from selenium import webdriver
+from selenium.webdriver.common.by import By
+from selenium.webdriver.support.ui import WebDriverWait
+from selenium.common.exceptions import WebDriverException
+from selenium.webdriver.support import expected_conditions as EC
+
+
+# Path to the root of the repo.
+REPO = pathlib.Path(__file__).parent.parent.parent
+BROWSERS = {
+    "chrome": (webdriver.Chrome, webdriver.ChromeOptions),
+    "firefox": (webdriver.Firefox, webdriver.FirefoxOptions),
+}
+
+
+def build_wheel() -> str:
+    """Build a wheel package of ``pygls`` and its testsuite.
+
+    In order to test pygls under pyodide, we need to load the code for both pygls and its
+    testsuite. This is done by building a wheel.
+
+    To avoid messing with the repo this is all done under a temp directory.
+    """
+
+    with tempfile.TemporaryDirectory() as tmpdir:
+        # Copy all required files.
+        dest = pathlib.Path(tmpdir)
+
+        # So that we don't have to fuss with packaging, copy the test suite into `pygls`
+        # as a sub module.
+        directories = [("pygls", "pygls"), ("tests", "pygls/tests")]
+
+        for src, target in directories:
+            shutil.copytree(REPO / src, dest / target)
+
+        files = ["pyproject.toml", "poetry.lock", "README.md", "ThirdPartyNotices.txt"]
+
+        for src in files:
+            shutil.copy(REPO / src, dest)
+
+        # Convert the lock file to requirements.txt.
+        # Ensures reproducible behavour for testing.
+        subprocess.run(
+            [
+                "poetry",
+                "export",
+                "-f",
+                "requirements.txt",
+                "--output",
+                "requirements.txt",
+            ],
+            cwd=dest,
+        )
+        subprocess.run(
+            ["poetry", "run", "pip", "install", "-r", "requirements.txt"], cwd=dest
+        )
+        # Build the wheel
+        subprocess.run(["poetry", "build", "--format", "wheel"], cwd=dest)
+        whl = list((dest / "dist").glob("*.whl"))[0]
+        shutil.copy(whl, REPO / "tests/pyodide_testrunner")
+
+        return whl.name
+
+
+def spawn_http_server(q: Queue, directory: str):
+    """A http server is needed to serve the files to the browser."""
+
+    handler_class = partial(SimpleHTTPRequestHandler, directory=directory)
+    server = ThreadingHTTPServer(("localhost", 0), handler_class)
+    q.put(server.server_port)
+
+    server.serve_forever()
+
+
+def main():
+    exit_code = 1
+    whl = build_wheel()
+
+    q = Queue()
+    server_process = Process(
+        target=spawn_http_server,
+        args=(q, REPO / "tests/pyodide_testrunner"),
+        daemon=True,
+    )
+    server_process.start()
+    port = q.get()
+
+    print("Running tests...")
+    try:
+        driver_cls, options_cls = BROWSERS[os.environ.get("BROWSER", "chrome")]
+
+        options = options_cls()
+        if "CI" in os.environ:
+            options.binary_location = "/usr/bin/google-chrome"
+            options.add_argument("--headless")
+
+        driver = driver_cls(options=options)
+        driver.get(f"http://localhost:{port}?whl={whl}")
+
+        wait = WebDriverWait(driver, 120)
+        try:
+            button = wait.until(EC.element_to_be_clickable((By.ID, "exit-code")))
+            exit_code = int(button.text)
+        except WebDriverException as e:
+            print(f"Error while running test: {e!r}")
+            exit_code = 1
+
+        console = driver.find_element(By.ID, "console")
+        print(console.text)
+    finally:
+        if hasattr(server_process, "kill"):
+            server_process.kill()
+        else:
+            server_process.terminate()
+
+    return exit_code
+
+
+if __name__ == "__main__":
+    sys.exit(main())
diff --git a/tests/pyodide_testrunner/test-runner.js b/tests/pyodide_testrunner/test-runner.js
new file mode 100644
index 0000000..dbbc01f
--- /dev/null
+++ b/tests/pyodide_testrunner/test-runner.js
@@ -0,0 +1,38 @@
+importScripts("https://cdn.jsdelivr.net/pyodide/v0.21.3/full/pyodide.js")
+
+// Used to redirect pyodide's stdout to the webpage.
+function patchedStdout(...args) {
+    postMessage(args[0])
+}
+
+async function runTests(whl) {
+    console.log("Loading pyodide")
+    let pyodide = await loadPyodide({
+        indexURL: "https://cdn.jsdelivr.net/pyodide/v0.21.3/full/"
+    })
+
+    console.log("Installing dependencies")
+    await pyodide.loadPackage("micropip")
+    await pyodide.runPythonAsync(`
+        import sys
+        import micropip
+
+        await micropip.install('pytest')
+        await micropip.install('pytest-asyncio')
+        await micropip.install('${whl}')
+    `)
+
+    console.log('Running testsuite')
+
+    // Patch stdout to redirect the output.
+    pyodide.globals.get('sys').stdout.write = patchedStdout
+    await pyodide.runPythonAsync(`
+        import pytest
+        exit_code = pytest.main(['--color', 'no', '--pyargs', 'pygls.tests'])
+    `)
+
+    postMessage({ exitCode: pyodide.globals.get('exit_code') })
+}
+
+let queryParams = new URLSearchParams(self.location.search)
+runTests(queryParams.get('whl'))