chore: add cross-platform webdriver tests

e2e/tests/coverage.test.mjs

@@ -0,0 +1,96 @@
+import assert from "node:assert/strict";
+import { readFile } from "node:fs/promises";
+import http from "node:http";
+import path from "node:path";
+import test from "node:test";
+import { allCoveredCommands, commandCoverage } from "../coverage-map.mjs";
+import { WebDriverClient } from "../lib/webdriver.mjs";
+
+function registeredCommands(source) {
+  const match = source.match(
+    /invoke_handler\(tauri::generate_handler!\[(.*?)\]\)/s,
+  );
+  assert.ok(match, "Could not locate Tauri generate_handler! command registry");
+  const withoutComments = match[1].replace(/\/\/[^\n]*/g, "");
+  return [
+    ...withoutComments.matchAll(/([A-Za-z_]\w*(?:::[A-Za-z_]\w*)*)\s*,/g),
+  ].map((item) => item[1]);
+}
+
+function commandHasExecutableEvidence(source, command) {
+  const name = command
+    .split("::")
+    .at(-1)
+    .replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
+  return new RegExp(
+    `(?:invoke|invokeError)\\(\\s*["']${name}["']|invokeContract\\(\\s*\\w+\\s*,\\s*["']${name}["']`,
+  ).test(source);
+}
+
+test("every Tauri command has exactly one E2E owner and evidence level", async () => {
+  const root =
+    process.env.DONUT_E2E_PROJECT_ROOT ??
+    path.resolve(import.meta.dirname, "../..");
+  const source = await readFile(
+    path.join(root, "src-tauri", "src", "lib.rs"),
+    "utf8",
+  );
+  const registered = registeredCommands(source);
+  const covered = allCoveredCommands();
+  assert.deepEqual(
+    [...new Set(covered)].sort(),
+    covered.slice().sort(),
+    "The E2E coverage map contains duplicate command ownership",
+  );
+  assert.deepEqual(covered.slice().sort(), registered.slice().sort());
+
+  for (const [name, entry] of Object.entries(commandCoverage)) {
+    assert.ok(
+      ["integration", "contract", "host-mutating"].includes(entry.level),
+      name,
+    );
+    assert.ok(entry.commands.length > 0, `${name} has no commands`);
+    if (entry.level === "host-mutating") {
+      assert.ok(
+        entry.reason?.length > 80,
+        `${name} needs an explicit safety reason`,
+      );
+      continue;
+    }
+
+    const suiteSource = await readFile(
+      path.join(root, "e2e", "tests", `${entry.suite}.test.mjs`),
+      "utf8",
+    );
+    for (const command of entry.commands) {
+      assert.equal(
+        commandHasExecutableEvidence(suiteSource, command),
+        true,
+        `${command} is assigned to ${entry.suite} but has no executable invoke evidence`,
+      );
+    }
+  }
+});
+
+test("WebDriver client preserves application values that contain an error field", async () => {
+  const server = http.createServer((_request, response) => {
+    response.writeHead(200, { "content-type": "application/json" });
+    response.end(
+      JSON.stringify({ value: { ok: false, error: "application error" } }),
+    );
+  });
+  await new Promise((resolve, reject) => {
+    server.once("error", reject);
+    server.listen(0, "127.0.0.1", resolve);
+  });
+  try {
+    const address = server.address();
+    const client = new WebDriverClient(`http://127.0.0.1:${address.port}`);
+    assert.deepEqual(await client.request("GET", "/value"), {
+      ok: false,
+      error: "application error",
+    });
+  } finally {
+    await new Promise((resolve) => server.close(resolve));
+  }
+});