Claude Opus 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've written `findings.csv` and `MIGRATION.md` to the repository root. The audit found **93 real call sites**: 91 `new Buffer(...)` and 2 `require('domain')`. No code calls `Buffer(...)` without `new`. No source files were changed.\n\n**How I scanned:** I tokenized all 204 `.js` files, so comments, string literals, template literals and regex literals were skipped. As a check, I compared the results with a plain `grep`. Every line `grep` found that the scan didn't count was one of 10 commented-out `new Buffer(` lines; those are listed in MIGRATION.md. Nothing calls the constructor under another name. `gridstore.js` reassigns `Buffer = require('buffer').Buffer`, which is the same constructor, so its two calls are counted. `examples/`, `docs/` and `index.js` have no findings.\n\n**By directory:**\n\n| Directory | Sites |\n|---|---|\n| `lib/` (the driver itself) | 24 |\n| `test/` | 61 (including both `require('domain')` calls) |\n| `dev/` | 8 |\n\n**Suggested replacements:** 65 \u2192 `Buffer.alloc`, 22 \u2192 `Buffer.from`, 4 \u2192 `Buffer.allocUnsafe`. The `allocUnsafe` ones are on the reply-parsing path in `connection.js`, where every byte is copied in before the buffer is used.\n\n**Sites that need special care:**\n- **The 6 message builders in `lib/mongodb/commands/`:** each one allocates a buffer with the old uninitialised constructor and sends it over the network. If the size worked out in advance is ever larger than what actually gets written, uninitialised memory goes to the server. I recommend `Buffer.alloc`, and `allocUnsafe` only once it's confirmed every byte gets written.\n- **`gridstore.js:1313`:** if a caller passes a number to `GridStore.write`, the old code quietly stored that many bytes of uninitialised memory. `Buffer.from` throws an error instead, so users will see a behaviour change.\n- **`chunk.js:36`:** the buffer is sized by the number of array elements, not the length of the joined string. Rewriting it as `Buffer.from(join)` would change what gets stored.\n- **`chunk.js:92`:** the buffer may be only partly filled, so it must be `Buffer.alloc`, not `allocUnsafe`.\n- **The two `require('domain')` tests** (`error_tests.js:107`, `exception_tests.js:32`) check that errors reach the caller's domain through `bindToCurrentDomain` in `lib/mongodb/db.js`. That function uses `process.domain`, which is outside your two patterns, so it isn't in the CSV. MIGRATION.md notes it so the tests and that function can be migrated together.\n- **Compatibility:** `package.json` says the driver supports Node `>=0.6.19`, but `Buffer.from` and `Buffer.alloc` need Node 4.5 or later. Either raise that minimum or add a small shim such as the `safe-buffer` package.\n\nThe scanner scripts are in `/tmp/audit/`, outside the repository, if you want to re-run them.",
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