vfs: avoid recursive readdir symlink cycles#64168
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I think I'd much prefer to see if there's a way to make the walk iterative rather than recursive but this works.
Track the active MemoryProvider recursive readdir traversal path so circular symlinks to directories stop recursing while still listing the symlink entries. Add sync, promise, and withFileTypes coverage. Fixes: nodejs#64148 Signed-off-by: Matteo Collina <hello@matteocollina.com>
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Fixes: #64148
MemoryProvider recursive readdir follows symlinked directories, but circular symlinks could recurse until the stack overflowed. This tracks the active traversal path so cycles are skipped while symlink entries are still listed.
Added regression coverage for sync, promise, mutual-cycle, and withFileTypes recursive readdir cases.
Tests:
git diff --check./node tools/eslint/node_modules/eslint/bin/eslint.js --max-warnings=0 --report-unused-disable-directives lib/internal/vfs/providers/memory.js test/parallel/test-vfs-readdir-symlink-recursive.js./node --experimental-vfs --expose-internals /tmp/test-vfs-memory-provider-source-wrapper.jsgit rev-parse HEAD~0 | xargs npx -q core-validate-commit --no-validate-metadata --tapNote: A full local rebuild was not completed in this environment; CI is building and running the test with the rebuilt binary.