adversarial-review: EISDIR crash when untracked directories exist + input size overflow

Bug Report

Environment

• codex-cli: 0.116.0
• codex-plugin-cc: 1.0.1
• Node.js: v22.12.0
• OS: macOS Darwin 24.4.0

Description

/codex:adversarial-review crashes with EISDIR: illegal operation on a directory, read when the working tree contains untracked directories. After fixing the EISDIR issue, it hits a secondary problem: Input exceeds the maximum length of 1048576 characters due to collecting all untracked file contents without a total size cap.

/codex:review works fine because it uses the native app server reviewer (runAppServerReview) which bypasses collectReviewContext. The adversarial-review path calls collectReviewContext → collectWorkingTreeContext → formatUntrackedFile, which has two issues.

Root Cause 1: EISDIR

In scripts/lib/git.mjs, formatUntrackedFile() does not check for directories before calling fs.readFileSync():

// line 136-149
function formatUntrackedFile(cwd, relativePath) {
  const absolutePath = path.join(cwd, relativePath);
  const stat = fs.statSync(absolutePath);
  // Missing: stat.isDirectory() check
  if (stat.size > MAX_UNTRACKED_BYTES) {
    return `...`;
  }
  const buffer = fs.readFileSync(absolutePath); // EISDIR if directory
  ...
}

git ls-files --others --exclude-standard can return paths that resolve to directories (e.g., in nested structures or when .gitignore doesn't fully exclude node_modules/).

Suggested Fix for EISDIR

function formatUntrackedFile(cwd, relativePath) {
  const absolutePath = path.join(cwd, relativePath);
  const stat = fs.statSync(absolutePath);
  if (stat.isDirectory()) {
    return `### ${relativePath}\n(skipped: directory)`;
  }
  if (stat.size > MAX_UNTRACKED_BYTES) {
  ...

Root Cause 2: Input Size Overflow

After fixing EISDIR, collectWorkingTreeContext successfully reads all untracked files but the combined content exceeds the 1MB Codex input limit. This happens in repos with large untracked trees (e.g., node_modules/, build artifacts, many temp files).

/codex:review avoids this because the native reviewer handles file collection internally with its own limits.

Suggested Fix for Input Size

Add a cumulative size budget to collectWorkingTreeContext, stopping untracked file collection once a threshold is reached (similar to how MAX_UNTRACKED_BYTES caps individual files).

Steps to Reproduce

1. Have a repo with untracked directories (e.g., node_modules/ not fully gitignored, or tmp/ with many files)
2. Run /codex:adversarial-review
3. Observe EISDIR crash (or after EISDIR fix, observe input size overflow)

Workaround

Ensure all large untracked directories are in .gitignore before running adversarial-review.

Start in scripts/lib/git.mjs by reading formatUntrackedFile and collectWorkingTreeContext, then reproduce /codex:adversarial-review with an untracked directory and a large untracked tree. Done means directories no longer cause EISDIR and collection stops before the combined input exceeds the limit.