Migrate from CommonJS to ESM - #2
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Wires up `npm test` (and `npm run test:spec`) using the `node:test` module, avoiding a new dependency. Covers the pure functions in helpers.js, the lookups in bandingCodes.js, and the main predicates in filters.js (dateFilter, completeChecklistFilter, locationFilter). Fixture lives in test/fixtures/ so tests don't depend on the large committed data files.
Adds ebd_*.{txt,csv}, MyEBirdData.csv, results.{csv,json}, and .DS_Store
to .gitignore so these don't sneak into a future `git add .`. Several
multi-megabyte files were already sitting untracked at the repo root.
@turf/center-of-mass returned a point in New York for West Haven, VT (the town has a complex border on Lake Champlain). turf.center returns the bounding-box center, which lands inside the polygon. Drops the now- unused @turf/center-of-mass import.
Mechanical conversion of the entire ebird-ext source to ECMAScript
modules. Adds "type": "module" to package.json so Node treats every
.js file as ESM.
- `require` / `module.exports` -> `import` / `export` throughout
- Local imports include the explicit `.js` extension (required by Node ESM)
- JSON imports use `with { type: 'json' }` (Node 18.20+ / 20.10+)
- `require('fs').promises` -> `import { promises as fs } from 'node:fs'`
- `__dirname` in scripts/arizona-records/BRCRecordsInJSonToCSV.js
reconstructed from `import.meta.url`
- index.js and hotspots.js export both named bindings and a default
object so existing React-site `import x from './ebird-ext/index.js'`
imports keep working alongside named imports from tests + CLI
- Two scripts that conditionally `require()` JSON files generated on
demand by readEBirdDb.js (joinTownJson.js, region-counts/joinRegionJson.js,
read250.js, readTownStats.js) use `createRequire` from `node:module`
so the conditional loading pattern survives intact
- One naming collision fixed: scripts/json2csv.js imports the json2csv
package as `json2csvPkg` to avoid shadowing a local `json2csv`
Transform variable
No behavior changes. 24 existing tests still pass.
Known follow-ups (deferred to hygiene phase):
- The parent site (birdinginvermont.com) bundles ebird-ext via Webpack
5.89; `with { type: 'json' }` requires Webpack 5.91+. The site won't
pick up these ESM changes until its submodule ref is bumped, at which
point Webpack also needs upgrading.
- `meow` is referenced by cli.js / norwich.js but missing from
package.json dependencies (pre-existing).
- The fs/io paths in index.js and hotspots.js still crash if imported
by a browser (pre-existing; will be addressed by splitting I/O into a
Node-only module).
This was referenced May 23, 2026
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Summary
Mechanical conversion of the entire ebird-ext source to ECMAScript modules. Adds
"type": "module"topackage.jsonso Node treats every.jsfile as ESM.require/module.exports→import/exportthroughout.jsextension (required by Node ESM)with { type: 'json' }(Node 18.20+ / 20.10+)require('fs').promises→import { promises as fs } from 'node:fs'__dirnameinscripts/arizona-records/BRCRecordsInJSonToCSV.jsreconstructed fromimport.meta.urlindex.jsandhotspots.jsexport both named bindings and a default object so existing React-siteimport x from './ebird-ext/index.js'imports keep working alongside named imports from tests + CLIrequire()JSON files generated on demand byreadEBirdDb.js(joinTownJson.js,region-counts/joinRegionJson.js,read250.js,readTownStats.js) usecreateRequirefromnode:moduleso the conditional loading pattern survives intactscripts/json2csv.jsimports thejson2csvpackage asjson2csvPkgto avoid shadowing a localjson2csvTransform variableNo behavior changes. 24 existing tests still pass.
Test plan
npm test— 24/24 passingnode --checkpasses on every.jsfilenode -e "import main from './index.js'; ..."loadsindex.jsand shows all 25 exportsnpm run build. Will need a follow-up PR there to bump Webpack 5.89 → 5.91+ forwith { type: 'json' }support before the submodule ref is updated.Known follow-ups (deferred to hygiene phase)
meowis referenced bycli.js/norwich.jsbut missing frompackage.json(pre-existing bug)fs/IO paths inindex.jsandhotspots.jsstill crash if imported by a browser (pre-existing; splitting I/O into a Node-only module is planned for the hygiene/refactor phase)