v1.2.0: guard allows computation-only inline one-liners; blocks --eval/--input-type, child_process, string-keyed access, stdin-piped scripts, deno/bun/php

test/guard.test.mjs

@@ -0,0 +1,78 @@
+// Guard rules for shell commands, focused on inline interpreter scripts.
+import test from 'node:test'
+import assert from 'node:assert/strict'
+import { shellViolation, inlineScriptViolation } from '../index.js'
+
+const ALLOW = [
+  // harmless computation one-liners
+  `node -e "console.log(1+1)"`,
+  `node -p "2**10"`,
+  `node --eval 'console.log([1,2,3].map(x => x * 2))'`,
+  `node --print="JSON.stringify({a: 1})"`,
+  `node -pe "Math.max(3, 7)"`,
+  `python3 -c "print(2**10)"`,
+  `python3 -c 'print(sum(range(100)))'`,
+  `ruby -e 'puts [1,2,3].sum'`,
+  `perl -e 'print 6*7, "\\n"'`,
+  `node -e 'console.log(JSON.parse(\`{"a":1}\`).a)'`,
+  // running files / tools is a normal command, not an inline script
+  'node --test test/',
+  'node build.mjs',
+  'node --check index.js',
+  'python3 manage.py migrate',
+  'node --version',
+  'python3 --version',
+  // unrelated commands
+  'git status',
+  'npm test 2>&1 | tail -5',
+]
+
+const BLOCK = [
+  // the reported gap
+  `node --input-type=module --eval "import fs from 'node:fs'; fs.readFileSync('a')"`,
+  `node --input-type=module -e "import('node:fs').then(m => m.writeFileSync('a', 'b'))"`,
+  // direct file / process access
+  `node -e "require('fs').writeFileSync('a', 'b')"`,
+  `node -e "require('child_process').execSync('cat f')"`,
+  `node -p "process.mainModule.require('fs')"`,
+  `node -e "fs['write'+'File']('a','b')"`,
+  `node -e "globalThis['req'+'uire']('fs')"`,
+  `node -e "this.constructor.constructor('return process')()"`,
+  `node -e "eval('requ'+'ire')('fs')"`,
+  `node -e "new Function('return process')()"`,
+  `node -e "fetch('http://x')"`,
+  `python3 -c "open('f','w').write('x')"`,
+  `python3 -c "import os; os.remove('f')"`,
+  `python3 -c "__import__('os').system('ls')"`,
+  `python3 -c "print(().__class__.__bases__[0].__subclasses__())"`,
+  `ruby -e "File.write('x', 1)"`,
+  'ruby -e "puts `ls`"',
+  `perl -e 'open(F, ">x")'`,
+  `deno eval "Deno.writeTextFileSync('x','y')"`,
+  `bun -e "Bun.write('x','y')"`,
+  `php -r "file_put_contents('x','y');"`,
+  // scripts we cannot inspect
+  'echo "require(1)" | node',
+  'cat script.js | node -',
+  'node - < script.js',
+  'python3 - < s.py',
+  // wrapped forms
+  `env FOO=1 node -e "require('fs')"`,
+  `sudo node -e "require('fs')"`,
+  `/usr/bin/node -e "require('fs')"`,
+  `ls && node -e "require('fs')"`,
+]
+
+test('harmless inline one-liners and normal commands are allowed', () => {
+  for (const c of ALLOW) assert.equal(shellViolation(c), null, `should allow: ${c}`)
+})
+
+test('file/process/network-capable or uninspectable inline scripts are blocked', () => {
+  for (const c of BLOCK) assert.ok(inlineScriptViolation(c) || shellViolation(c), `should block: ${c}`)
+})
+
+test('denial message points at the right tools', () => {
+  const m = shellViolation(`node -e "require('fs').readFileSync('a')"`)
+  assert.match(m, /read\/grep\/edit/)
+  assert.match(m, /computation-only one-liners are fine/)
+})