Claude Sonnet 5.5 (effort default (no --effort flag) · thinking on) on Find every deprecated API call in a large repo and write a migration checklist

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  "result": "I found 93 call sites across the 204 `.js` files and wrote `findings.csv` and `MIGRATION.md` in the repo root. I didn't modify any source files.\n\n- **`new Buffer()`:** 91 sites. There are 24 in `lib`, 59 in `test` and 8 in `dev`.\n- **Plain `Buffer(...)`:** none.\n- **`require('domain')`:** 2 sites, in `test/tests/functional/error_tests.js:107` and `exception_tests.js:32`.\n- **`docs` and `examples`:** no call sites.\n\nI counted with a small tokenizer that skips comments, strings and regexes, and it left out 10 commented-out `new Buffer` lines. I cross-checked its output against a plain grep. The only differences were those commented lines and `lib/mongodb/gridfs/gridstore.js:1311`, which isn't a Buffer call.\n\n**Replacements in the CSV**\n- Size arguments get `Buffer.alloc(size)`.\n- In `lib`, buffers that are fully overwritten before use are marked `Buffer.allocUnsafe(size)` or `Buffer.alloc(size)`.\n- String and array arguments get `Buffer.from(...)`.\n- The two `domain` sites point to `AsyncLocalStorage` plus explicit error handling.\n\n**Cases `MIGRATION.md` flags for care**\n- **`lib/mongodb/gridfs/gridstore.js:1313`:** the argument could be a non-string. If it were a number, `Buffer.from` would throw where `new Buffer` treated it as a size.\n- **`lib/mongodb/connection/connection.js`:** 10 sites in the message-parsing hot path, so performance is worth checking.\n- **`test/tests/functional/raw_tests.js:208`:** an intentionally invalid buffer, so confirm the test still throws as expected.\n- **The `domain` tests:** they aren't a drop-in swap. `lib/mongodb/db.js:1635` reads `process.domain` and calls `domain.bind(callback)`. That isn't a `require`, so I didn't count it, but removing domain support means changing that code too.\n- **Node versions:** `Buffer.from` and `Buffer.alloc` need Node 4.5 or later and 5.10 or later respectively, which is newer than this driver era targets.\n\nThe checklist in `MIGRATION.md` is grouped by directory with per-file line numbers.",
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