fix: preserve tty when forwarding codex

Preserve inherited stdout/stderr for terminal-attached forwarded Codex runs while keeping output capture for non-TTY fallback and retry handling.

Fixes #436

Author: ndycode

scripts/codex.js

@@ -253,11 +253,30 @@ function replaceRequestedModel(args, nextModel) {
 	return nextArgs;
 }
 
-function forwardToRealCodexOnce(codexBin, args, env = process.env, cleanup) {
+function shouldCaptureForwardedCodexOutput(env = process.env) {
+	const override = (env.CODEX_MULTI_AUTH_CAPTURE_FORWARD_OUTPUT ?? "").trim();
+	if (override === "1") {
+		return true;
+	}
+	if (override === "0") {
+		return false;
+	}
+	// Windows child processes can report undefined isTTY; treat that as non-TTY so retry capture remains available.
+	return process.stdout.isTTY !== true || process.stderr.isTTY !== true;
+}
+
+function forwardToRealCodexOnce(
+	codexBin,
+	args,
+	env = process.env,
+	cleanup,
+	options = {},
+) {
 	return new Promise((resolve) => {
 		let settled = false;
 		let stdout = "";
 		let stderr = "";
+		const captureOutput = options.captureOutput === true;
 		const finalize = (exitCode) => {
 			if (settled) {
 				return;
@@ -270,33 +289,46 @@ function forwardToRealCodexOnce(codexBin, args, env = process.env, cleanup) {
 			}
 			resolve({
 				exitCode,
+				// No-capture output stays empty by design so retry parsing cannot
+				// reintroduce pipes that break terminal passthrough.
 				output: `${stdout}\n${stderr}`.trim(),
 			});
 		};
 
 		const command = codexBin.launchWithNode ? process.execPath : codexBin.path;
 		const commandArgs = codexBin.launchWithNode ? [codexBin.path, ...args] : args;
-		const child = spawn(command, commandArgs, {
-			stdio: ["inherit", "pipe", "pipe"],
-			env,
-		});
-
-		child.stdout?.on("data", (chunk) => {
-			const text = typeof chunk === "string" ? chunk : chunk.toString("utf8");
-			stdout += text;
-			process.stdout.write(chunk);
-		});
-		child.stderr?.on("data", (chunk) => {
-			const text = typeof chunk === "string" ? chunk : chunk.toString("utf8");
-			stderr += text;
-			process.stderr.write(chunk);
-		});
-
-		child.once("error", (error) => {
+		let child;
+		const failLaunch = (error) => {
 			const message = `Failed to launch real Codex CLI: ${String(error)}`;
 			stderr += `${stderr ? "\n" : ""}${message}`;
 			console.error(message);
 			finalize(1);
+		};
+		try {
+			child = spawn(command, commandArgs, {
+				stdio: captureOutput ? ["inherit", "pipe", "pipe"] : "inherit",
+				env,
+			});
+		} catch (error) {
+			failLaunch(error);
+			return;
+		}
+
+		if (captureOutput) {
+			child.stdout?.on("data", (chunk) => {
+				const text = typeof chunk === "string" ? chunk : chunk.toString("utf8");
+				stdout += text;
+				process.stdout.write(chunk);
+			});
+			child.stderr?.on("data", (chunk) => {
+				const text = typeof chunk === "string" ? chunk : chunk.toString("utf8");
+				stderr += text;
+				process.stderr.write(chunk);
+			});
+		}
+
+		child.once("error", (error) => {
+			failLaunch(error);
 		});
 
 		child.once("close", (code, signal) => {
@@ -333,6 +365,9 @@ async function forwardToRealCodex(codexBin, rawArgs, baseEnv = process.env) {
 			compatibility.args,
 			compatibility.env,
 			compatibility.cleanup,
+			{
+				captureOutput: shouldCaptureForwardedCodexOutput(compatibility.env),
+			},
 		);
 		lastExitCode = result.exitCode;
 		if (result.exitCode === 0) {

test/codex-bin-wrapper.test.ts

@@ -1231,6 +1231,80 @@ describe("codex bin wrapper", () => {
 		);
 	});
 
+	it("honors explicit capture output override for unsupported-model retries", () => {
+		const fixtureRoot = createWrapperFixture();
+		const stateDir = join(fixtureRoot, "retry-state-capture-override");
+		mkdirSync(stateDir, { recursive: true });
+		const fakeBin = createCustomFakeCodexBin(fixtureRoot, [
+			"const fs = require('node:fs');",
+			"const path = require('node:path');",
+			"const counterPath = path.join(process.env.CODEX_MULTI_AUTH_TEST_STATE_DIR, 'attempt.txt');",
+			"const attempt = fs.existsSync(counterPath) ? Number(fs.readFileSync(counterPath, 'utf8')) : 0;",
+			"fs.writeFileSync(counterPath, String(attempt + 1), 'utf8');",
+			"const args = process.argv.slice(2);",
+			"const modelIndex = args.indexOf('--model');",
+			"const requestedModel = modelIndex >= 0 ? args[modelIndex + 1] : 'unknown-model';",
+			"if (attempt === 0) {",
+			`  console.error("ERROR: {\\\"type\\\":\\\"error\\\",\\\"status\\\":400,\\\"error\\\":{\\\"type\\\":\\\"invalid_request_error\\\",\\\"message\\\":\\\"The '" + requestedModel + "' model is not supported when using Codex with a ChatGPT account.\\\"}}");`,
+			"  process.exit(1);",
+			"}",
+			"console.log(`FORWARDED:${args.join(' ')}`);",
+			"process.exit(0);",
+		]);
+		const originalHome = join(fixtureRoot, "codex-home");
+		mkdirSync(originalHome, { recursive: true });
+		writeFileSync(join(originalHome, "auth.json"), "{}\n", "utf8");
+		writeFileSync(join(originalHome, "config.toml"), "", "utf8");
+
+		const result = runWrapper(fixtureRoot, ["exec", "status", "--model", "gpt-5.5"], {
+			CODEX_MULTI_AUTH_CAPTURE_FORWARD_OUTPUT: "1",
+			CODEX_MULTI_AUTH_REAL_CODEX_BIN: fakeBin,
+			CODEX_MULTI_AUTH_TEST_STATE_DIR: stateDir,
+			CODEX_HOME: originalHome,
+		});
+
+		const output = combinedOutput(result);
+		expect(result.status).toBe(0);
+		expect(readFileSync(join(stateDir, "attempt.txt"), "utf8")).toBe("2");
+		expect(output).toContain("Retrying with gpt-5.4");
+		expect(output).toContain(
+			'FORWARDED:exec status --model gpt-5.4 -c cli_auth_credentials_store="file"',
+		);
+	});
+
+	it("can forward without capturing child stdio for terminal-sensitive Codex runs", () => {
+		const fixtureRoot = createWrapperFixture();
+		const stateDir = join(fixtureRoot, "no-capture-state");
+		mkdirSync(stateDir, { recursive: true });
+		const originalHome = join(fixtureRoot, "codex-home");
+		mkdirSync(originalHome, { recursive: true });
+		writeFileSync(join(originalHome, "config.toml"), "", "utf8");
+		const fakeBin = createCustomFakeCodexBin(fixtureRoot, [
+			"const fs = require('node:fs');",
+			"const path = require('node:path');",
+			"const counterPath = path.join(process.env.CODEX_MULTI_AUTH_TEST_STATE_DIR, 'attempt.txt');",
+			"const attempt = fs.existsSync(counterPath) ? Number(fs.readFileSync(counterPath, 'utf8')) : 0;",
+			"fs.writeFileSync(counterPath, String(attempt + 1), 'utf8');",
+			"console.error(\"The 'gpt-5.5' model is not supported when using Codex with a ChatGPT account.\");",
+			"process.exit(1);",
+		]);
+
+		const result = runWrapper(fixtureRoot, ["exec", "status", "--model", "gpt-5.5"], {
+			CODEX_MULTI_AUTH_CAPTURE_FORWARD_OUTPUT: "0",
+			CODEX_MULTI_AUTH_REAL_CODEX_BIN: fakeBin,
+			CODEX_MULTI_AUTH_TEST_STATE_DIR: stateDir,
+			CODEX_HOME: originalHome,
+		});
+
+		const output = combinedOutput(result);
+		expect(result.status).toBe(1);
+		expect(readFileSync(join(stateDir, "attempt.txt"), "utf8")).toBe("1");
+		expect(output).toContain(
+			"The 'gpt-5.5' model is not supported when using Codex with a ChatGPT account.",
+		);
+		expect(output).not.toContain("Retrying with gpt-5.4");
+	});
+
 	it("retries GPT-5.5 after access-denied style model errors", () => {
 		const fixtureRoot = createWrapperFixture();
 		const stateDir = join(fixtureRoot, "retry-state-access");