Files
ECC/tests/hooks/config-protection.test.js
Emad DoughanandGitHub e7b3ba07bb fix(config-protection): match protected filenames case-insensitively (#2543)
On a case-insensitive filesystem (macOS APFS/HFS+, Windows NTFS) a write to
`.ESLINTRC.JS` lands on the exact same inode as `.eslintrc.js`, but the guard
looked the basename up in PROTECTED_FILES with a case-sensitive `Set.has`.
Every entry in that Set is lowercase, so any case-variant path missed the
branch entirely and returned exit 0 — a single Write silently overwrote a
live config while the hook reported success.

Reproduced on macOS APFS: `.eslintrc.js` and `.ESLINTRC.JS` share one inode,
yet the hook returned exit 2 for the former and exit 0 for the latter, and the
uppercase write replaced the real config's contents.

This is a one-step bypass of the whole guard and needs no shell access, unlike
the known delete-then-recreate route.

Fix: also test `basename.toLowerCase()`. All 32 PROTECTED_FILES entries are
already lowercase, so the fallback is exact. On a genuinely case-sensitive
filesystem this costs at most a false positive on a distinct file whose name
differs from a protected one by case alone.

Behaviour deliberately unchanged: first-time creation is still allowed (the
bootstrap affordance), non-config paths still pass through, and the existing
lstat/ENOENT fail-closed semantics are untouched.

Test: adds a case-variant case that asserts exit 2. It guards itself with an
inode comparison and skips on case-sensitive filesystems rather than asserting
something untrue there. Verified in both directions — it FAILS against the
unpatched hook (`Got 0; 0 !== 2`) and passes with the fix. Suite: 9/9.
2026-07-22 12:17:04 -04:00

365 lines
12 KiB
JavaScript

/**
* Tests for scripts/hooks/config-protection.js via run-with-flags.js
*/
const assert = require('assert');
const fs = require('fs');
const os = require('os');
const path = require('path');
const { spawnSync } = require('child_process');
const runner = path.join(__dirname, '..', '..', 'scripts', 'hooks', 'run-with-flags.js');
function test(name, fn) {
try {
fn();
console.log(` ✓ ${name}`);
return true;
} catch (error) {
console.log(` ✗ ${name}`);
console.log(` Error: ${error.message}`);
return false;
}
}
function runHook(input, env = {}) {
const rawInput = typeof input === 'string' ? input : JSON.stringify(input);
const result = spawnSync('node', [runner, 'pre:config-protection', 'scripts/hooks/config-protection.js', 'standard,strict'], {
input: rawInput,
encoding: 'utf8',
env: {
...process.env,
ECC_HOOK_PROFILE: 'standard',
...env
},
timeout: 15000,
stdio: ['pipe', 'pipe', 'pipe']
});
return {
code: Number.isInteger(result.status) ? result.status : 1,
stdout: result.stdout || '',
stderr: result.stderr || ''
};
}
function runCustomHook(pluginRoot, hookId, relScriptPath, input, env = {}) {
const rawInput = typeof input === 'string' ? input : JSON.stringify(input);
const result = spawnSync('node', [runner, hookId, relScriptPath, 'standard,strict'], {
input: rawInput,
encoding: 'utf8',
env: {
...process.env,
CLAUDE_PLUGIN_ROOT: pluginRoot,
ECC_HOOK_PROFILE: 'standard',
...env
},
timeout: 15000,
stdio: ['pipe', 'pipe', 'pipe']
});
return {
code: Number.isInteger(result.status) ? result.status : 1,
stdout: result.stdout || '',
stderr: result.stderr || ''
};
}
function runTests() {
console.log('\n=== Testing config-protection ===\n');
let passed = 0;
let failed = 0;
if (
test('blocks protected config file edits through run-with-flags', () => {
const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'ecc-config-protect-'));
try {
const absPath = path.join(tmpDir, '.eslintrc.js');
fs.writeFileSync(absPath, 'module.exports = {};');
const input = {
tool_name: 'Write',
tool_input: {
file_path: absPath,
content: 'module.exports = {};'
}
};
const result = runHook(input);
assert.strictEqual(result.code, 2, 'Expected protected config edit to be blocked');
assert.strictEqual(result.stdout, '', 'Blocked hook should not echo raw input');
assert.ok(result.stderr.includes('BLOCKED: Modifying .eslintrc.js is not allowed.'), `Expected block message, got: ${result.stderr}`);
} finally {
try {
fs.rmSync(tmpDir, { recursive: true, force: true });
} catch {
// best-effort cleanup
}
}
})
)
passed++;
else failed++;
if (
test('passes through safe file edits unchanged', () => {
const input = {
tool_name: 'Write',
tool_input: {
file_path: 'src/index.js',
content: 'console.log("ok");'
}
};
const rawInput = JSON.stringify(input);
const result = runHook(input);
assert.strictEqual(result.code, 0, 'Expected safe file edit to pass');
assert.strictEqual(result.stdout, rawInput, 'Expected exact raw JSON passthrough');
assert.strictEqual(result.stderr, '', 'Expected no stderr for safe edits');
})
)
passed++;
else failed++;
if (
test('blocks truncated protected config payloads instead of failing open', () => {
const rawInput = JSON.stringify({
tool_name: 'Write',
tool_input: {
file_path: '.eslintrc.js',
content: 'x'.repeat(1024 * 1024 + 2048)
}
});
const result = runHook(rawInput);
assert.strictEqual(result.code, 2, 'Expected truncated protected payload to be blocked');
assert.strictEqual(result.stdout, '', 'Blocked truncated payload should not echo raw input');
assert.ok(result.stderr.includes('Hook input exceeded 1048576 bytes'), `Expected size warning, got: ${result.stderr}`);
assert.ok(result.stderr.includes('truncated payload'), `Expected truncated payload warning, got: ${result.stderr}`);
})
)
passed++;
else failed++;
if (
test('allows first-time creation of a protected config file', () => {
const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'ecc-config-protect-'));
try {
const absPath = path.join(tmpDir, 'eslint.config.mjs');
const input = {
tool_name: 'Write',
tool_input: {
file_path: absPath,
content: 'export default [];'
}
};
const rawInput = JSON.stringify(input);
const result = runHook(input);
assert.strictEqual(result.code, 0, `Expected exit 0 for first-time creation, got ${result.code}; stderr: ${result.stderr}`);
assert.strictEqual(result.stdout, rawInput, 'Expected raw passthrough when creation is allowed');
assert.strictEqual(result.stderr, '', `Expected no stderr for first-time creation, got: ${result.stderr}`);
} finally {
try {
fs.rmSync(tmpDir, { recursive: true, force: true });
} catch {
// best-effort cleanup
}
}
})
)
passed++;
else failed++;
if (
test('allows first-time creation when the parent directory does not exist yet', () => {
const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'ecc-config-protect-'));
try {
// Path under a non-existent subdirectory — statSync returns ENOENT
// on the final segment, which should be treated as "does not exist"
// and allow the write. (Agent or CLI is expected to create parents
// during the Write itself; this hook does not need to.)
const absPath = path.join(tmpDir, 'no-such-parent', '.prettierrc');
const input = {
tool_name: 'Write',
tool_input: {
file_path: absPath,
content: '{}'
}
};
const rawInput = JSON.stringify(input);
const result = runHook(input);
assert.strictEqual(result.code, 0, `Expected exit 0 for ENOENT path, got ${result.code}; stderr: ${result.stderr}`);
assert.strictEqual(result.stdout, rawInput, 'Expected raw passthrough when path does not exist');
} finally {
try {
fs.rmSync(tmpDir, { recursive: true, force: true });
} catch {
// best-effort cleanup
}
}
})
)
passed++;
else failed++;
if (
test('blocks protected paths that exist as a dangling symlink', () => {
const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'ecc-config-protect-'));
try {
const missingTarget = path.join(tmpDir, 'nowhere.js');
const linkPath = path.join(tmpDir, '.eslintrc.js');
try {
fs.symlinkSync(missingTarget, linkPath);
} catch (err) {
// Windows without Developer Mode or certain sandboxes disallow
// symlinks. Skip cleanly rather than fail the suite.
if (err.code === 'EPERM' || err.code === 'EACCES') {
console.log(' (skipped: symlink creation not permitted here)');
return;
}
throw err;
}
const input = {
tool_name: 'Write',
tool_input: {
file_path: linkPath,
content: 'module.exports = {};'
}
};
const result = runHook(input);
assert.strictEqual(result.code, 2, `Expected exit 2 for dangling symlink, got ${result.code}; stderr: ${result.stderr}`);
assert.strictEqual(result.stdout, '', 'Blocked hook should not echo raw input');
assert.ok(result.stderr.includes('BLOCKED: Modifying .eslintrc.js is not allowed.'), `Expected block message, got: ${result.stderr}`);
} finally {
try {
fs.rmSync(tmpDir, { recursive: true, force: true });
} catch {
// best-effort cleanup
}
}
})
)
passed++;
else failed++;
if (
test('blocks case-variant writes that resolve to an existing protected config', () => {
const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'ecc-config-protect-'));
try {
const realPath = path.join(tmpDir, '.eslintrc.js');
const variantPath = path.join(tmpDir, '.ESLINTRC.JS');
fs.writeFileSync(realPath, 'module.exports = { rules: { "no-explicit-any": "error" } };');
// Only meaningful on a case-insensitive filesystem (macOS APFS/HFS+,
// Windows NTFS), where the uppercase path is the SAME inode. On a
// case-sensitive filesystem the variant is a genuinely different file
// and the write is harmless, so skip rather than assert.
let sameFile = false;
try {
sameFile = fs.lstatSync(variantPath).ino === fs.lstatSync(realPath).ino;
} catch {
sameFile = false;
}
if (!sameFile) {
console.log(' (skipped: case-sensitive filesystem)');
return;
}
const result = runHook({
tool_name: 'Write',
tool_input: {
file_path: variantPath,
content: 'module.exports = { rules: {} }; // WEAKENED'
}
});
assert.strictEqual(result.code, 2, `Case-variant write must be blocked: it overwrites ${path.basename(realPath)} on this filesystem. Got ${result.code}; stderr: ${result.stderr}`);
assert.strictEqual(result.stdout, '', 'Blocked hook should not echo raw input');
} finally {
try {
fs.rmSync(tmpDir, { recursive: true, force: true });
} catch {
// best-effort cleanup
}
}
})
)
passed++;
else failed++;
if (
test('still blocks writes to an existing protected config file', () => {
const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), 'ecc-config-protect-'));
try {
const absPath = path.join(tmpDir, '.eslintrc.js');
fs.writeFileSync(absPath, 'module.exports = { rules: {} };');
const input = {
tool_name: 'Edit',
tool_input: {
file_path: absPath,
content: 'module.exports = { rules: { "no-console": "off" } };'
}
};
const result = runHook(input);
assert.strictEqual(result.code, 2, 'Expected exit 2 when modifying an existing protected config');
assert.strictEqual(result.stdout, '', 'Blocked hook should not echo raw input');
assert.ok(result.stderr.includes('BLOCKED: Modifying .eslintrc.js is not allowed.'), `Expected block message, got: ${result.stderr}`);
} finally {
try {
fs.rmSync(tmpDir, { recursive: true, force: true });
} catch {
// best-effort cleanup
}
}
})
)
passed++;
else failed++;
if (
test('legacy hooks do not echo raw input when they fail without stdout', () => {
const pluginRoot = path.join(__dirname, '..', `tmp-runner-plugin-${Date.now()}`);
const scriptDir = path.join(pluginRoot, 'scripts', 'hooks');
const scriptPath = path.join(scriptDir, 'legacy-block.js');
try {
fs.mkdirSync(scriptDir, { recursive: true });
fs.writeFileSync(scriptPath, '#!/usr/bin/env node\nprocess.stderr.write("blocked by legacy hook\\n");\nprocess.exit(2);\n');
const rawInput = JSON.stringify({
tool_name: 'Write',
tool_input: {
file_path: '.eslintrc.js',
content: 'module.exports = {};'
}
});
const result = runCustomHook(pluginRoot, 'pre:legacy-block', 'scripts/hooks/legacy-block.js', rawInput);
assert.strictEqual(result.code, 2, 'Expected failing legacy hook exit code to propagate');
assert.strictEqual(result.stdout, '', 'Expected failing legacy hook to avoid raw passthrough');
assert.ok(result.stderr.includes('blocked by legacy hook'), `Expected legacy hook stderr, got: ${result.stderr}`);
} finally {
try {
fs.rmSync(pluginRoot, { recursive: true, force: true });
} catch {
// best-effort cleanup
}
}
})
)
passed++;
else failed++;
console.log(`\nResults: Passed: ${passed}, Failed: ${failed}`);
process.exit(failed > 0 ? 1 : 0);
}
runTests();