Automatically reconnect single ADB head unit

server/tests/adb.test.ts

@@ -80,6 +80,42 @@ describe("read-only ADB collector", () => {
     });
   });
 
+  it("automatically discovers exactly one device and refuses ambiguous connections", async () => {
+    const calls: string[][] = [];
+    const execute: AdbExecutor = async (_executable, arguments_) => {
+      calls.push([...arguments_]);
+      if (arguments_[0] === "devices") {
+        return { stdout: "List of devices attached\nAUTO-MG4\tdevice product:saic model:autus\n", stderr: "" };
+      }
+      if (arguments_.at(-1) === "get-state") return { stdout: "device\n", stderr: "" };
+      return { stdout: "value\n", stderr: "" };
+    };
+    const status = await collectAdbStatus({ ...enabledConfig, serial: null }, execute);
+    expect(status).toMatchObject({ available: true, value: { state: "connected" } });
+    expect(calls[0]).toEqual(["devices"]);
+    for (const arguments_ of calls.slice(1)) expect(arguments_.slice(0, 2)).toEqual(["-s", "AUTO-MG4"]);
+
+    const multiple: AdbExecutor = async () => ({
+      stdout: "List of devices attached\nMG4\tdevice\nPHONE\tdevice\n",
+      stderr: ""
+    });
+    await expect(collectAdbStatus({ ...enabledConfig, serial: null }, multiple)).resolves.toMatchObject({
+      available: false,
+      state: "ambiguous"
+    });
+  });
+
+  it("reports an automatically discovered device awaiting authorization", async () => {
+    const execute: AdbExecutor = async () => ({
+      stdout: "List of devices attached\nAUTO-MG4\tunauthorized\n",
+      stderr: ""
+    });
+    await expect(collectAdbStatus({ ...enabledConfig, serial: null }, execute)).resolves.toMatchObject({
+      available: false,
+      state: "unauthorized"
+    });
+  });
+
   it("keeps individual fields unavailable when a connected device only partially responds", async () => {
     const execute: AdbExecutor = async (_executable, arguments_) => {
       if (arguments_.at(-1) === "get-state") return { stdout: "device\n", stderr: "" };

server/tests/config.test.ts

@@ -11,8 +11,8 @@ describe("ADB configuration", () => {
     });
   });
 
-  it("requires a constrained serial when enabled", () => {
-    expect(() => loadConfig({ NODE_ENV: "test", ADB_ENABLED: "true" })).toThrow("ADB_SERIAL is required");
+  it("supports automatic discovery or a constrained pinned serial when enabled", () => {
+    expect(loadConfig({ NODE_ENV: "test", ADB_ENABLED: "true" }).adb).toMatchObject({ enabled: true, serial: null });
     expect(() =>
       loadConfig({ NODE_ENV: "test", ADB_ENABLED: "true", ADB_SERIAL: "serial; shell command" })
     ).toThrow();