script

Author: mdjastrzebski

.github/workflows/ci.yaml

@@ -44,7 +44,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        react-version: ["^19.0.0", "^19.1.0", "^19.2.0", "latest"]
+        react-version: ["~19.0.0", "~19.1.0", "~19.2.0", "latest"]
     steps:
       - uses: actions/checkout@v5
 

.github/workflows/nightly.yaml

@@ -26,7 +26,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        react-version: ["^19.0.0", "^19.1.0", "^19.2.0", "latest"]
+        react-version: ["~19.0.0", "~19.1.0", "~19.2.0", "latest"]
     steps:
       - uses: actions/checkout@v5
 

docs/agents/commands.md

@@ -8,7 +8,7 @@ Use Bun to run repository scripts.
 - `bun run test` runs the Jest test suite.
 - `bun run test:ci` runs tests with coverage.
 - `bun run lint` runs ESLint.
-- `bun run prettier` checks formatting.
-- `bun run prettier:fix` writes formatting changes.
+- `bun run format` checks formatting.
+- `bun run format:fix` writes formatting changes.
 - `bun run validate` runs typecheck, test, lint, and formatting checks.
 - `bun run validate:fix` runs formatting and lint fixes, then typecheck and tests.

eslint.config.js

@@ -5,6 +5,17 @@ import simpleImportSort from "eslint-plugin-simple-import-sort";
 export default tseslint.config(
   eslint.configs.recommended,
   ...tseslint.configs.strictTypeChecked,
+  {
+    files: ["**/*.{js,mjs,cjs}"],
+    ...tseslint.configs.disableTypeChecked,
+    languageOptions: {
+      globals: {
+        console: "readonly",
+        fetch: "readonly",
+        process: "readonly",
+      },
+    },
+  },
   {
     files: ["src/**/*.{ts,tsx}"],
     languageOptions: {

package.json

@@ -43,10 +43,10 @@
     "lint": "eslint .",
     "typecheck": "tsc --noEmit",
     "test:watch": "jest --watch",
-    "validate": "bun run typecheck && bun run test && bun run lint && bun run prettier",
-    "validate:fix": "bun run prettier:fix && bun run lint --fix && bun run typecheck && bun run test -u",
-    "prettier": "prettier --check .",
-    "prettier:fix": "prettier --write .",
+    "validate": "bun run typecheck && bun run test && bun run lint && bun run format",
+    "validate:fix": "bun run format:fix && bun run lint --fix && bun run typecheck && bun run test -u",
+    "format": "prettier --check .",
+    "format:fix": "prettier --write .",
     "release": "release-it"
   },
   "dependencies": {
@@ -56,6 +56,9 @@
   "peerDependencies": {
     "react": "^19.0.0"
   },
+  "testRenderer": {
+    "supportedReactRange": ">=19.0.0 <19.3.0"
+  },
   "devDependencies": {
     "@eslint/js": "^9.21.0",
     "@jest/globals": "^30.2.0",

scripts/check-react-release-guard.mjs

@@ -1,5 +1,15 @@
 import packageJson from "../package.json" with { type: "json" };
 
+function getSupportedReactRange() {
+  const supportedReactRange = packageJson.testRenderer?.supportedReactRange;
+
+  if (typeof supportedReactRange !== "string" || supportedReactRange.trim() === "") {
+    throw new Error("package.json must define testRenderer.supportedReactRange");
+  }
+
+  return supportedReactRange;
+}
+
 function parseSemver(version) {
   const match = /^(\d+)\.(\d+)\.(\d+)(?:[-+].*)?$/.exec(version);
 
@@ -71,13 +81,11 @@ function parseExclusiveUpperBounds(range) {
   return upperBounds;
 }
 
-function getReactSupportWindow(range) {
+function getSupportedReactCeiling(range) {
   const upperBounds = parseExclusiveUpperBounds(range);
 
   if (upperBounds.length === 0) {
-    throw new Error(
-      `Could not derive a supported React ceiling from peerDependencies.react: ${range}`,
-    );
+    throw new Error(`Could not derive a supported React ceiling from range: ${range}`);
   }
 
   return upperBounds.reduce((lowest, candidate) =>
@@ -89,16 +97,16 @@ function formatSemver(version) {
   return `${version.major}.${version.minor}.${version.patch}`;
 }
 
-function getSupportedLineLabel(upperBound) {
+function getSupportedLinesLabel(upperBound) {
   if (upperBound.patch === 0 && upperBound.minor > 0) {
-    return `${upperBound.major}.${upperBound.minor - 1}.x`;
+    return `React ${upperBound.major}.0.x through ${upperBound.major}.${upperBound.minor - 1}.x`;
   }
 
   if (upperBound.minor === 0 && upperBound.patch === 0) {
-    return `${upperBound.major - 1}.x`;
+    return `React ${upperBound.major - 1}.x`;
   }
 
-  return `<${formatSemver(upperBound)}`;
+  return `React versions <${formatSemver(upperBound)}`;
 }
 
 async function getLatestReactVersion() {
@@ -130,20 +138,24 @@ async function main() {
   const latestVersion = await getLatestReactVersion();
   const parsedLatest = parseSemver(latestVersion);
   const peerRange = packageJson.peerDependencies?.react ?? "<missing>";
-  const upperBound = getReactSupportWindow(peerRange);
-  const supportedLineLabel = getSupportedLineLabel(upperBound);
+  const supportedReactRange = getSupportedReactRange();
+  const supportedReactCeiling = getSupportedReactCeiling(supportedReactRange);
+  const supportedLinesLabel = getSupportedLinesLabel(supportedReactCeiling);
 
-  if (compareSemver(parsedLatest, upperBound) < 0) {
-    console.log(`React ${latestVersion} is still within the supported line (${supportedLineLabel}).`);
+  if (compareSemver(parsedLatest, supportedReactCeiling) < 0) {
+    console.log(
+      `React ${latestVersion} is still within the supported window (${supportedLinesLabel}).`,
+    );
     return;
   }
 
   const failureLines = [
-    `React ${latestVersion} has been released on npm, but this repository only supports up to React ${supportedLineLabel}.`,
+    `React ${latestVersion} has been released on npm, but this repository currently supports only ${supportedLinesLabel}.`,
     `A plain npm install of test-renderer is no longer safely constrained for the newest React release.`,
     `Current peerDependencies.react: ${peerRange}`,
-    `Current derived React ceiling: <${formatSemver(upperBound)}`,
-    `Update the compatibility policy, add support for the new React line, and tighten the published peer dependency range before relying on latest again.`,
+    `Configured supportedReactRange: ${supportedReactRange}`,
+    `Current derived React ceiling: <${formatSemver(supportedReactCeiling)}`,
+    `Update testRenderer.supportedReactRange or tighten peerDependencies.react before relying on latest again.`,
   ];
 
   throw new Error(failureLines.join("\n"));

src/__tests__/react-release-guard.test.ts

@@ -0,0 +1,42 @@
+import { spawnSync } from "node:child_process";
+import { resolve } from "node:path";
+import { describe, expect, test } from "@jest/globals";
+
+const scriptPath = resolve(process.cwd(), "scripts/check-react-release-guard.mjs");
+
+describe("react release guard", () => {
+  test("accepts the latest release within the supported React line", () => {
+    const result = spawnSync(process.execPath, [scriptPath], {
+      encoding: "utf8",
+      env: {
+        ...process.env,
+        REACT_RELEASE_GUARD_LATEST: "19.2.5",
+      },
+    });
+
+    expect(result.status).toBe(0);
+    expect(result.stdout).toContain(
+      "React 19.2.5 is still within the supported window (React 19.0.x through 19.2.x).",
+    );
+    expect(result.stderr).toBe("");
+  });
+
+  test("fails when the latest release moves past the supported React line", () => {
+    const result = spawnSync(process.execPath, [scriptPath], {
+      encoding: "utf8",
+      env: {
+        ...process.env,
+        REACT_RELEASE_GUARD_LATEST: "19.3.0",
+      },
+    });
+
+    expect(result.status).toBe(1);
+    expect(result.stdout).toBe("");
+    expect(result.stderr).toContain(
+      "React 19.3.0 has been released on npm, but this repository currently supports only React 19.0.x through 19.2.x.",
+    );
+    expect(result.stderr).toContain("Current peerDependencies.react: ^19.0.0");
+    expect(result.stderr).toContain("Configured supportedReactRange: >=19.0.0 <19.3.0");
+    expect(result.stderr).toContain("Current derived React ceiling: <19.3.0");
+  });
+});