Claude Haiku 5.5 (effort default (no --effort flag) · thinking on) + Claude Opus 5.5 (effort default (no --effort flag) · thinking on · + scanner (claude-haiku-5.5) subagents) on Find every deprecated API call in a large repo and write a migration checklist

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  "result": "I've written `findings.csv` and `MIGRATION.md` in the repo root. The audit found **93 call sites**: 91 `new Buffer(...)`, no `Buffer(...)` calls without `new`, and 2 `require('domain')`. I didn't change any source files.\n\n| Directory | `new Buffer()` | `require('domain')` |\n|---|---|---|\n| lib/ | 24 | 0 |\n| test/ | 59 | 2 |\n| dev/ | 8 | 0 |\n| examples/, root `index.js` | 0 | 0 |\n\ndocs/ contains no `.js` files, so it had nothing to scan.\n\n**How I checked the results:** I ran one scanner each on lib/, test/, examples/ and dev/, in parallel, and checked root `index.js` myself. Separately, I parsed every `.js` file with a JavaScript parser (acorn), which skips comments and strings automatically. All files parsed, and both methods found exactly the same file and line for all 93 sites. The only discrepancy was in the test/ scanner's report: it listed all 61 sites correctly but miscounted the total as 59. Commented-out uses (e.g. `insert_tests.js:1202`) are excluded. The one alias, `Buffer = require('buffer').Buffer` in `gridstore.js:12`, keeps the name `Buffer`, so its two uses are counted.\n\n**Sites that need special care (detailed in MIGRATION.md):**\n- **`lib/mongodb/gridfs/gridstore.js:1313`:** `new Buffer(data, 'binary')` takes whatever the user passes to `GridStore.write`. If that's a number, `Buffer.from` throws where the old code didn't, so it needs a type check.\n- **`lib/mongodb/gridfs/chunk.js:36`:** this is an existing bug. The buffer is sized by the number of array elements but receives the joined string, so data is cut off if any element is longer than one character. Replacing it with `Buffer.from(data.join(''), 'binary')` fixes that too.\n- **`lib/mongodb/connection/connection.js:399`:** the buffer size comes from the network and the buffer fills over several reads. Use `Buffer.alloc` here, not `allocUnsafe`, so a cut-off message can't expose old memory.\n- **`lib/mongodb/commands/*` (6 sites):** these run for every message sent to the server. Only switch to `allocUnsafe` after confirming every byte gets written.\n- **The two domain tests (`error_tests.js:107`, `exception_tests.js:32`)** test the driver's `process.domain` support in `lib/mongodb/db.js:1635`. That code doesn't call `require('domain')`, so it isn't in the CSV. Whether to rewrite the tests depends on whether that support is kept.\n- **`insert_tests.js:1313-1315`** pass a fractional size (`16777216/3`); the checklist suggests rounding it down explicitly.\n- **Node version:** `package.json` allows Node 0.6.19 and later, but `Buffer.alloc` and `Buffer.from` need Node 4.5 or later. Migrating lib/ means either raising that minimum or using a compatibility shim such as `safe-buffer`.\n\nWhere the code makes it clear, the CSV gives a specific replacement: `Buffer.from` for strings, arrays and base64, and `Buffer.allocUnsafe` or `Buffer.concat` where the buffer is immediately fully overwritten. All other size-only calls default to `Buffer.alloc`.",
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