google · michael-kerscher · Feb 6, 2025 · Dec 13, 2024 · Jan 24, 2025
diff --git a/tests/src/objects/playground.ts b/tests/src/objects/playground.ts
@@ -0,0 +1,106 @@
+import { $, browser } from "@wdio/globals";
+
+export default class Playground {
+  /**
+   * stores a playground mock
+   */
+  mock: WebdriverIO.Mock;
+
+  get area() {
+    return $(".ace_content");
+  }
+  get start_button() {
+    return $("button.play-button");
+  }
+  get stderr() {
+    return $("code.result.stderr");
+  }
+  get stdout() {
+    return $("code.result.stdout");
+  }
+
+  /**
+   * activate the playground by clicking into it
+   */
+  async activate() {
+    // clicking into the content is necessary for the button to be displayed
+    await this.area.waitForClickable();
+    await this.area.click();
+  }
+
+  /**
+   *  run the code in the playground editor
+   */
+  async run() {
+    // clicking the button triggers action
+    await this.start_button.waitForClickable();
+    // await browser.debug();
+    await this.start_button.click();
+  }
+
+  /**
+   * generate a new mock for the playground that overrides playground requests
+   */
+  async mock_new() {
+    return browser.mock("https://play.rust-lang.org/execute", {
+      method: "post",
+    });
+  }
+
+  /**
+   * reset the mock object
+   */
+  async mock_reset() {
+    this.mock.clear();
+  }
+
+  /**
+   * mock a successful playground run
+   * @param stdout a string that is expected to be in stdout
+   */
+  async mock_success(stdout: string) {
+    this.mock = await this.mock_new();
+
+    // be aware that there is a still a preflight OPTIONS request
+    this.mock.respond(
+      {
+        success: true,
+        exitDetail: "Exited with status 0",
+        stdout: stdout,
+        stderr:
+          "   Compiling playground v0.0.1 (/playground)\n    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.62s\n     Running `target/debug/playground`\n",
+      },
+      {
+        headers: {
+          "Access-Control-Allow-Origin": "*",
+        },
+        fetchResponse: false,
+      }
+    );
+  }
+
+  /**
+   * mock a failed run that would be caused if a `fn fail()` is added without any function body
+   */
+  async mock_fail() {
+    // mock the response so this test does not rely on the playground backend to be working
+    this.mock = await this.mock_new();
+
+    // be aware that there is a still a preflight OPTIONS request
+    this.mock.respond(
+      {
+        success: false,
+        exitDetail: "Exited with status 101",
+        stdout: "",
+        stderr:
+          '   Compiling playground v0.0.1 (/playground)\nerror: expected one of `->`, `where`, or `{`, found `}`\n --> src/main.rs:5:1\n  |\n4 |     fn fail()\n  |        ----  - expected one of `->`, `where`, or `{`\n  |        |\n  |        while parsing this `fn`\n5 | }\n  | ^ unexpected token\n\nerror: free function without a body\n --> src/main.rs:4:5\n  |\n4 |     fn fail()\n  |     ^^^^^^^^^- help: provide a definition for the function: `{ <body> }`\n\nerror: could not compile `playground` (bin "playground") due to 2 previous errors\n',
+      },
+      {
+        headers: {
+          "Access-Control-Allow-Origin": "*",
+        },
+        fetchResponse: false,
+      }
+    );
+  }
+}
diff --git a/tests/src/playground.test.ts b/tests/src/playground.test.ts
@@ -0,0 +1,49 @@
+import { describe, it } from "mocha";
+import { expect, browser } from "@wdio/globals";
+import { Key } from "webdriverio";
+import Playground from "./objects/playground";
+
+describe("Playground", () => {
+  beforeEach(async () => {
+    // this page contains a hello world playground
+    await browser.url("/hello-world/hello-world.html");
+  });
+
+  it("exists and is shown but output fields do not yet exist", async () => {
+    const playground = new Playground();
+    // ensure a playground exists and pre-state is as expected
+    await expect(playground.area).toExist();
+    await expect(playground.start_button).toExist();
+    await expect(playground.start_button).not.toBeDisplayed();
+    await expect(playground.stderr).not.toExist();
+    await expect(playground.stdout).not.toExist();
+  });
+
+  it("executes the hello world code and prints the hello message", async () => {
+    const playground = new Playground();
+    await playground.mock_success("Hello world!\n");
+    await playground.activate();
+    await playground.run();
+
+    await expect(playground.stdout).toBeDisplayed();
+    await expect(playground.stderr).not.toBeDisplayed();
+    await expect(playground.stdout).toHaveText("Hello world!");
+  });
+
+  it("shows error messages in stderr if the code is broken", async () => {
+    const playground = new Playground();
+    await playground.mock_fail();
+    await playground.activate();
+    // append some failing code to the editor that is now in focus
+    await browser.keys([Key.Enter, "fn expect_failure()"]);
+    await playground.run();
+
+    await expect(playground.stdout).toBeDisplayed();
+    await expect(playground.stderr).toBeDisplayed();
+    // check for error message in stderr
+    await expect(playground.stderr).toHaveText(
+      expect.stringContaining("error: could not compile")
+    );
+    await expect(playground.stdout).toHaveText("No output");
+  });
+});