Avoid env alias when capturing environment

Fixes #17

Author: sindresorhus

index.js

@@ -5,7 +5,8 @@ import defaultShell from 'default-shell';
 
 const args = [
 	'-ilc',
-	'echo -n "_SHELL_ENV_DELIMITER_"; env; echo -n "_SHELL_ENV_DELIMITER_"; exit',
+	// Use the command builtin to avoid shell aliases or functions named `env`.
+	'echo -n "_SHELL_ENV_DELIMITER_"; command env; echo -n "_SHELL_ENV_DELIMITER_"; exit',
 ];
 
 const env = {

test.js

@@ -1,3 +1,5 @@
+import fs from 'node:fs/promises';
+import path from 'node:path';
 import test from 'ava';
 import {shellEnv, shellEnvSync} from './index.js';
 
@@ -17,6 +19,32 @@ test('sync', t => {
 	t.is(env.ZSH_TMUX_AUTOSTART, 'false');
 });
 
+test('sync - ignores env alias', async t => {
+	const temporaryDirectoryPrefix = path.join(process.cwd(), 'temporary-shell-env-');
+	const temporaryDirectory = await fs.mkdtemp(temporaryDirectoryPrefix);
+
+	try {
+		const bashConfigurationPath = path.join(temporaryDirectory, '.bashrc');
+		const bashWrapperPath = path.join(temporaryDirectory, 'bash-wrapper.sh');
+		const bashWrapperContents = [
+			'#!/bin/sh',
+			`HOME="${temporaryDirectory}"`,
+			'export HOME',
+			'exec /bin/bash "$@"',
+			'',
+		].join('\n');
+
+		await fs.writeFile(bashConfigurationPath, 'alias env="printf no"\n');
+		await fs.writeFile(bashWrapperPath, bashWrapperContents);
+		await fs.chmod(bashWrapperPath, 0o755);
+
+		const env = shellEnvSync(bashWrapperPath);
+		t.is(env.HOME, temporaryDirectory);
+	} finally {
+		await fs.rm(temporaryDirectory, {recursive: true, force: true});
+	}
+});
+
 test('async - with custom shell', async t => {
 	const shell = '/bin/bash';
 	const env = await shellEnv(shell);