Check that generated compat-data is up to date on CI

Makefile

@@ -101,7 +101,7 @@ bootstrap-flowcheck: bootstrap-only
 	$(YARN) gulp build-babel-types
 	$(MAKE) build-typings
 
-lint-ci: lint-js-ci lint-ts-ci
+lint-ci: lint-js-ci lint-ts-ci check-compat-data
 
 lint-js-ci: bootstrap-only
 	$(MAKE) lint-js
@@ -125,6 +125,12 @@ fix-js:
 fix-json:
 	$(YARN) prettier "{$(COMMA_SEPARATED_SOURCES)}/*/test/fixtures/**/options.json" --write --loglevel warn
 
+check-compat-data:
+	cd packages/babel-compat-data; CHECK_COMPAT_DATA=true $(YARN) run build-data
+
+build-compat-data:
+	cd packages/babel-compat-data; $(YARN) run build-data
+
 clean: test-clean
 	rm -f .npmrc
 	rm -rf packages/babel-polyfill/browser*

packages/babel-compat-data/scripts/build-data.js

@@ -4,7 +4,6 @@ const fs = require("fs");
 const path = require("path");
 const semver = require("semver");
 const flattenDeep = require("lodash/flattenDeep");
-const isEqual = require("lodash/isEqual");
 const mapValues = require("lodash/mapValues");
 const pickBy = require("lodash/pickBy");
 const { unreleasedLabels } = require("@babel/helper-compilation-targets");
@@ -297,18 +296,20 @@ for (const target of ["plugin", "corejs2-built-in"]) {
   );
   const dataPath = path.join(__dirname, `../data/${target}s.json`);
 
-  if (process.argv[2] === "--check") {
-    const currentData = require(dataPath);
+  const stringified = JSON.stringify(newData, null, 2) + "\n";
+  if (process.env.CHECK_COMPAT_DATA) {
+    const currentData = fs.readFileSync(dataPath, "utf8");
 
-    if (!isEqual(currentData, newData)) {
+    // Compare as JSON strings to also check keys ordering
+    if (currentData !== stringified) {
       console.error(
         "The newly generated plugin/built-in data does not match the current " +
-          "files. Re-run `npm run build-data`."
+          "files. Re-run `make build-compat-data`."
       );
       process.exitCode = 1;
       break;
     }
   } else {
-    fs.writeFileSync(dataPath, `${JSON.stringify(newData, null, 2)}\n`);
+    fs.writeFileSync(dataPath, stringified);
   }
 }