Give the voice preflight a speaking microphone

interviewer-voice launched Chromium with its built-in fake beep for a
microphone. Under a local sound server the beep is too short for the
microphone check that enables Join, so the test failed on a desktop and
passed only on a runner without one. It now captures test-voice.wav,
like the two other tests that need a working microphone check, through
one launch argument they share.

Author: jserv

tests/browser/interviewer-voice.test.js

@@ -4,6 +4,7 @@ import {
   DEFAULT_RUNTIME_CONFIG,
   launchChromium,
   read,
+  FAKE_SPEECH_CAPTURE,
   startStaticServer,
 } from "./source.js";
 
@@ -37,6 +38,7 @@ before(async () => {
     args: [
       "--use-fake-device-for-media-stream",
       "--use-fake-ui-for-media-stream",
+      FAKE_SPEECH_CAPTURE,
       "--autoplay-policy=no-user-gesture-required",
     ],
   });

tests/browser/preflight-speech.test.js

@@ -1,8 +1,11 @@
 // Browser playback cannot prove physical audibility through system effects.
 import { after, before, test } from "node:test";
 import assert from "node:assert/strict";
-import { fileURLToPath } from "node:url";
-import { DEFAULT_RUNTIME_CONFIG, startStaticServer } from "./source.js";
+import {
+  DEFAULT_RUNTIME_CONFIG,
+  FAKE_SPEECH_CAPTURE,
+  startStaticServer,
+} from "./source.js";
 
 let browser;
 let server;
@@ -14,7 +17,7 @@ before(async () => {
       args: [
         "--use-fake-device-for-media-stream",
         "--use-fake-ui-for-media-stream",
-        `--use-file-for-fake-audio-capture=${fileURLToPath(new URL("../../web/audio/test-voice.wav", import.meta.url))}`,
+        FAKE_SPEECH_CAPTURE,
       ],
     });
   } catch (error) {

tests/browser/run-shortcut.test.js

@@ -3,11 +3,11 @@
 // the interview is on.
 import { after, before, test } from "node:test";
 import assert from "node:assert/strict";
-import { fileURLToPath } from "node:url";
 
 import {
   DEFAULT_RUNTIME_CONFIG,
   launchChromium,
+  FAKE_SPEECH_CAPTURE,
   startStaticServer,
 } from "./source.js";
 
@@ -263,7 +263,7 @@ async function mediaBrowser(t) {
     args: [
       "--use-fake-device-for-media-stream",
       "--use-fake-ui-for-media-stream",
-      `--use-file-for-fake-audio-capture=${fileURLToPath(new URL("../../web/audio/test-voice.wav", import.meta.url))}`,
+      FAKE_SPEECH_CAPTURE,
     ],
   });
   t.after(() => media.close());

tests/browser/source.js

@@ -173,6 +173,11 @@ export function memoryStorage() {
   };
 }
 
+// Speech as the fake microphone, not Chromium's built-in beep: under a local
+// sound server the beep is too short for the microphone check that enables
+// Join, so a test passes on a runner without one and fails on a desktop.
+export const FAKE_SPEECH_CAPTURE = `--use-file-for-fake-audio-capture=${join(root, "web", "audio", "test-voice.wav")}`;
+
 /// The browser, or null when there is no browser to be had. Shared so that
 /// every file launching one agrees on what a missing Playwright or an
 /// undownloaded Chromium means. `make check` installs neither, so a null here