fix: close stdin on vp invocations to avoid Windows runner hang

src/index.ts

@@ -10,7 +10,7 @@ import { State, Outputs } from "./types.js";
 import type { Inputs } from "./types.js";
 import { resolveNodeVersionFile } from "./node-version-file.js";
 import { configAuthentication, propagateProjectNpmrcAuth } from "./auth.js";
-import { getConfiguredProjectDir } from "./utils.js";
+import { getConfiguredProjectDir, EMPTY_STDIN } from "./utils.js";
 
 async function runMain(inputs: Inputs): Promise<void> {
   // Mark that post action should run
@@ -29,7 +29,7 @@ async function runMain(inputs: Inputs): Promise<void> {
   // Step 3: Set up Node.js version if specified
   if (nodeVersion) {
     info(`Setting up Node.js ${nodeVersion} via vp env use...`);
-    await exec("vp", ["env", "use", nodeVersion]);
+    await exec("vp", ["env", "use", nodeVersion], { input: EMPTY_STDIN });
   }
 
   // Step 4: Configure registry authentication
@@ -61,7 +61,11 @@ async function runMain(inputs: Inputs): Promise<void> {
 
 async function printViteVersion(cwd: string): Promise<void> {
   try {
-    const result = await getExecOutput("vp", ["--version"], { cwd, silent: true });
+    const result = await getExecOutput("vp", ["--version"], {
+      cwd,
+      silent: true,
+      input: EMPTY_STDIN,
+    });
     const versionOutput = result.stdout.trim();
     info(versionOutput);
 

src/run-install.test.ts

@@ -0,0 +1,68 @@
+import { describe, it, expect, afterEach, beforeEach, vi } from "vite-plus/test";
+import { getExecOutput } from "@actions/exec";
+import { runViteInstall } from "./run-install.js";
+import type { Inputs } from "./types.js";
+
+vi.mock("@actions/core", () => ({
+  startGroup: vi.fn(),
+  endGroup: vi.fn(),
+  setFailed: vi.fn(),
+  info: vi.fn(),
+  error: vi.fn(),
+}));
+
+vi.mock("@actions/exec", () => ({
+  getExecOutput: vi.fn(),
+}));
+
+const baseInputs: Inputs = {
+  version: "latest",
+  nodeVersion: undefined,
+  nodeVersionFile: undefined,
+  workingDirectory: undefined,
+  runInstall: [{}],
+  sfw: false,
+  cache: false,
+  cacheDependencyPath: undefined,
+  registryUrl: undefined,
+  scope: undefined,
+};
+
+describe("runViteInstall", () => {
+  beforeEach(() => {
+    process.env.GITHUB_WORKSPACE = "/tmp/workspace";
+    vi.mocked(getExecOutput).mockResolvedValue({ exitCode: 0, stdout: "", stderr: "" });
+  });
+
+  afterEach(() => {
+    vi.resetAllMocks();
+    delete process.env.GITHUB_WORKSPACE;
+  });
+
+  // Regression test for https://github.com/voidzero-dev/setup-vp/issues/90
+  //
+  // On Windows runners stdin is not a TTY. Vite+ routes the package-manager
+  // `.cmd` shims through PowerShell, whose `.ps1` wrappers read stdin and block
+  // forever when the child's stdin pipe is left open and empty, hanging the job
+  // for hours. `@actions/exec` only closes the child's stdin when `input` is a
+  // truthy value, so we must pass an empty Buffer (EOF) to avoid the hang.
+  it("closes stdin so vp install cannot hang on Windows runners", async () => {
+    await runViteInstall(baseInputs);
+
+    expect(getExecOutput).toHaveBeenCalledTimes(1);
+    const options = vi.mocked(getExecOutput).mock.calls[0][2];
+    expect(options?.input).toBeDefined();
+    expect(Buffer.isBuffer(options?.input)).toBe(true);
+    expect(options?.input?.length).toBe(0);
+  });
+
+  it("closes stdin for the sfw-wrapped install too", async () => {
+    await runViteInstall({ ...baseInputs, sfw: true });
+
+    const [cmd, args, options] = vi.mocked(getExecOutput).mock.calls[0];
+    expect(cmd).toBe("sfw");
+    expect(args).toEqual(["vp", "install"]);
+    expect(Buffer.isBuffer(options?.input)).toBe(true);
+    expect(options?.input?.length).toBe(0);
+  });
+});

src/run-install.ts

@@ -1,7 +1,7 @@
 import { startGroup, endGroup, setFailed, info, error as logError } from "@actions/core";
 import { getExecOutput } from "@actions/exec";
 import type { Inputs } from "./types.js";
-import { getConfiguredProjectDir, getInstallCwd } from "./utils.js";
+import { getConfiguredProjectDir, getInstallCwd, EMPTY_STDIN } from "./utils.js";
 
 const MAX_ERROR_TAIL = 4000;
 
@@ -31,6 +31,9 @@ export async function runViteInstall(inputs: Inputs): Promise<void> {
       const { exitCode, stdout, stderr } = await getExecOutput(cmd, args, {
         cwd,
         ignoreReturnCode: true,
+        // Close stdin (EOF) so the package-manager PowerShell wrappers Vite+
+        // spawns on Windows do not block on an open stdin pipe. See EMPTY_STDIN.
+        input: EMPTY_STDIN,
       });
       endGroup();
 

src/utils.ts

@@ -7,6 +7,23 @@ import type { Inputs } from "./types.js";
 import { LockFileType } from "./types.js";
 import type { LockFileInfo } from "./types.js";
 
+/**
+ * Empty stdin payload (EOF) for child processes we spawn.
+ *
+ * On Windows runners stdin is not a TTY. Vite+ routes the package-manager
+ * `.cmd` shims (pnpm/npm/yarn) through PowerShell, whose `.ps1` wrappers
+ * introspect stdin (`$MyInvocation.ExpectingInput`) and block forever when the
+ * child's stdin pipe is left open and empty, hanging the job for hours until
+ * GitHub cancels it. `@actions/exec` leaves the child's stdin open unless
+ * `input` is set, so we pass an empty buffer to send EOF immediately.
+ *
+ * A `Buffer` (not `""`, which is falsy) is required: `@actions/exec` only calls
+ * `cp.stdin.end(input)` when `input` is truthy.
+ *
+ * See https://github.com/voidzero-dev/setup-vp/issues/90
+ */
+export const EMPTY_STDIN = Buffer.alloc(0);
+
 export function getVitePlusHome(): string {
   const home = process.platform === "win32" ? process.env.USERPROFILE : process.env.HOME;
   return join(home || homedir(), ".vite-plus");