fix: callback ref cleanup compatibility across React 17–19 (#760)

* test: cover packed React compatibility

* fix: gate callback ref cleanup by React version

* fix: parse React ref cleanup support conservatively

* test: compose callback refs across React versions

* test: simplify packed React compatibility

* test: run packed harness as native TypeScript

Author: thebuilder

.github/workflows/test.yml

@@ -60,6 +60,11 @@ jobs:
         run: pnpm add -D react@${{ matrix.react }} react-dom@${{ matrix.react }}
       - name: Validate types
         run: pnpm tsc
+      - name: Build package
+        run: pnpm build
+      - name: Test packed package
+        if: ${{ matrix.react != 'latest' }}
+        run: pnpm run compat:packed -- ${{ matrix.react }}
       - name: Run test
         run: |
           pnpm exec playwright install

fixtures/react-compat/entry.jsx

@@ -0,0 +1,15 @@
+import { useInView, useOnInView } from "react-intersection-observer";
+
+function CompatibilityFixture() {
+  const callbackRef = useOnInView(() => {});
+  const { ref: stateRef } = useInView();
+
+  return (
+    <>
+      <div ref={callbackRef} />
+      <div ref={stateRef} />
+    </>
+  );
+}
+
+window.__COMPAT_FIXTURE__ = CompatibilityFixture;

fixtures/react-compat/rsbuild.config.mjs

@@ -0,0 +1,11 @@
+import { defineConfig } from "@rsbuild/core";
+import { pluginReact } from "@rsbuild/plugin-react";
+
+export default defineConfig({
+  plugins: [pluginReact()],
+  source: {
+    entry: {
+      index: "./entry.jsx",
+    },
+  },
+});

package.json

@@ -44,6 +44,7 @@
   "scripts": {
     "prebuild": "rm -rf dist lib",
     "build": "tsup && mkdir dist/esm && cp dist/index.mjs dist/esm/index.js",
+    "compat:packed": "node scripts/compat/packed.mts",
     "postbuild": "attw --pack && publint && size-limit",
     "dev": "run-p dev:*",
     "dev:package": "tsup src/index.tsx --watch",
@@ -122,6 +123,8 @@
   "devDependencies": {
     "@arethetypeswrong/cli": "^0.18.2",
     "@biomejs/biome": "^2.3.10",
+    "@rsbuild/core": "1.5.13",
+    "@rsbuild/plugin-react": "1.4.2",
     "@size-limit/preset-small-lib": "^12.0.0",
     "@testing-library/jest-dom": "^6.9.1",
     "@testing-library/react": "^16.3.1",