fix(webpack): handle packages with strict exports in runtimeDependencies

[jkossis]

Current Behavior

When using runtimeDependencies in the webpack config, the build fails if the specified package has an exports field that doesn't include ./package.json:

Error [ERR_PACKAGE_PATH_NOT_EXPORTED]: Package subpath './package.json' is not defined by "exports"

Expected Behavior

The build should succeed. The package.json file exists and is readable via the filesystem—it's only inaccessible via require.resolve() due to the exports restriction.

Fix

Catch the ERR_PACKAGE_PATH_NOT_EXPORTED error and fall back to resolving the main entry point, then locate package.json via filesystem path manipulation.

Example Package

@as-integrations/express5 has this exports field which triggers the bug:

"exports": {
  ".": {
    "import": "./dist/esm/index.js",
    "require": "./dist/cjs/index.js"
  }
}

Note: ./package.json is not exported, but the file exists and is readable.

Reproduction

1. Create an Nx workspace with a Node app using webpack
2. Add a runtime dependency that has strict exports (e.g., @as-integrations/express5)
3. Configure webpack:

new NxAppWebpackPlugin({
  // ...
  generatePackageJson: true,
  runtimeDependencies: ["@as-integrations/express5"],
})

4. Run the build → fails with ERR_PACKAGE_PATH_NOT_EXPORTED

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[graphite-app]

Unhandled error: If require.resolve(dep) fails inside the catch block (e.g., the dependency doesn't exist or has other resolution issues), the error will propagate uncaught and crash the build. While this may be intentional for truly missing dependencies, it creates inconsistent error handling - the outer try-catch suggests all resolution errors should be handled gracefully.

Fix: Wrap the fallback resolution in its own try-catch:

try {
  depPkgJson = require.resolve(`${dep}/package.json`);
} catch {
  try {
    const depMain = require.resolve(dep);
    const nodeModulesIndex = depMain.lastIndexOf('node_modules');
    if (nodeModulesIndex === -1) continue;
    depPkgJson = path.join(
      depMain.slice(0, nodeModulesIndex),
      'node_modules',
      dep,
      'package.json'
    );
  } catch {
    continue; // Skip if package cannot be resolved at all
  }
}

Spotted by Graphite Agent



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[jkossis]

The error was previously propagating uncaught, this is just to handle this one case.