feat(node-resolve): add ignoreSideEffectsForRoot option

packages/node-resolve/README.md

@@ -157,6 +157,10 @@ Specifies the root directory from which to resolve modules. Typically used when
 rootDir: path.join(process.cwd(), '..')
 ```
 
+## `ignoreSideEffectsForRoot`
+
+If you use the `sideEffects` property in the package.json, by default this is respected for files in the root package. Set to `true` to ignore the `sideEffects` configuration for the root package.
+
 ## Preserving symlinks
 
 This plugin honours the rollup [`preserveSymlinks`](https://rollupjs.org/guide/en/#preservesymlinks) option.

packages/node-resolve/src/index.js

@@ -34,15 +34,16 @@ const defaults = {
   // which deploy both ESM .mjs and CommonJS .js files as ESM.
   extensions: ['.mjs', '.js', '.json', '.node'],
   resolveOnly: [],
-  moduleDirectories: ['node_modules']
+  moduleDirectories: ['node_modules'],
+  ignoreSideEffectsForRoot: false
 };
 export const DEFAULTS = deepFreeze(deepMerge({}, defaults));
 
 export function nodeResolve(opts = {}) {
   const { warnings } = handleDeprecatedOptions(opts);
 
   const options = { ...defaults, ...opts };
-  const { extensions, jail, moduleDirectories } = options;
+  const { extensions, jail, moduleDirectories, ignoreSideEffectsForRoot } = options;
   const conditionsEsm = [...baseConditionsEsm, ...(options.exportConditions || [])];
   const conditionsCjs = [...baseConditionsCjs, ...(options.exportConditions || [])];
   const packageInfoCache = new Map();
@@ -51,7 +52,7 @@ export function nodeResolve(opts = {}) {
   const useBrowserOverrides = mainFields.indexOf('browser') !== -1;
   const isPreferBuiltinsSet = options.preferBuiltins === true || options.preferBuiltins === false;
   const preferBuiltins = isPreferBuiltinsSet ? options.preferBuiltins : true;
-  const rootDir = options.rootDir || process.cwd();
+  const rootDir = resolve(options.rootDir || process.cwd());
   let { dedupe } = options;
   let rollupOptions;
 
@@ -200,7 +201,9 @@ export function nodeResolve(opts = {}) {
         preserveSymlinks,
         useBrowserOverrides,
         baseDir,
-        moduleDirectories
+        moduleDirectories,
+        rootDir,
+        ignoreSideEffectsForRoot
       });
 
       const resolved =

packages/node-resolve/src/resolveImportSpecifiers.js

@@ -43,7 +43,9 @@ async function resolveId({
   preserveSymlinks,
   useBrowserOverrides,
   baseDir,
-  moduleDirectories
+  moduleDirectories,
+  rootDir,
+  ignoreSideEffectsForRoot
 }) {
   let hasModuleSideEffects = () => null;
   let hasPackageEntry = true;
@@ -58,7 +60,9 @@ async function resolveId({
       pkgPath,
       mainFields,
       preserveSymlinks,
-      useBrowserOverrides
+      useBrowserOverrides,
+      rootDir,
+      ignoreSideEffectsForRoot
     });
 
     ({ packageInfo, hasModuleSideEffects, hasPackageEntry, packageBrowserField } = info);
@@ -180,7 +184,9 @@ export default async function resolveImportSpecifiers({
   preserveSymlinks,
   useBrowserOverrides,
   baseDir,
-  moduleDirectories
+  moduleDirectories,
+  rootDir,
+  ignoreSideEffectsForRoot
 }) {
   let lastResolveError;
 
@@ -197,7 +203,9 @@ export default async function resolveImportSpecifiers({
       preserveSymlinks,
       useBrowserOverrides,
       baseDir,
-      moduleDirectories
+      moduleDirectories,
+      rootDir,
+      ignoreSideEffectsForRoot
     });
 
     if (result instanceof ResolveError) {

packages/node-resolve/src/util.js

@@ -40,7 +40,16 @@ export function getMainFields(options) {
 }
 
 export function getPackageInfo(options) {
-  const { cache, extensions, pkg, mainFields, preserveSymlinks, useBrowserOverrides } = options;
+  const {
+    cache,
+    extensions,
+    pkg,
+    mainFields,
+    preserveSymlinks,
+    useBrowserOverrides,
+    rootDir,
+    ignoreSideEffectsForRoot
+  } = options;
   let { pkgPath } = options;
 
   if (cache.has(pkgPath)) {
@@ -130,13 +139,15 @@ export function getPackageInfo(options) {
     packageInfo.browserMappedMain = false;
   }
 
-  const packageSideEffects = pkg.sideEffects;
-  if (typeof packageSideEffects === 'boolean') {
-    internalPackageInfo.hasModuleSideEffects = () => packageSideEffects;
-  } else if (Array.isArray(packageSideEffects)) {
-    internalPackageInfo.hasModuleSideEffects = createFilter(packageSideEffects, null, {
-      resolve: pkgRoot
-    });
+  if (!ignoreSideEffectsForRoot || rootDir !== pkgRoot) {
+    const packageSideEffects = pkg.sideEffects;
+    if (typeof packageSideEffects === 'boolean') {
+      internalPackageInfo.hasModuleSideEffects = () => packageSideEffects;
+    } else if (Array.isArray(packageSideEffects)) {
+      internalPackageInfo.hasModuleSideEffects = createFilter(packageSideEffects, null, {
+        resolve: pkgRoot
+      });
+    }
   }
 
   cache.set(pkgPath, internalPackageInfo);

packages/node-resolve/test/fixtures/root-package-side-effect/index.js

@@ -0,0 +1 @@
+import './side-effect.js';

packages/node-resolve/test/fixtures/root-package-side-effect/package.json

@@ -0,0 +1,4 @@
+{
+  "main": "./index.js",
+  "sideEffects": false
+}

packages/node-resolve/test/fixtures/root-package-side-effect/side-effect.js

@@ -0,0 +1 @@
+console.log('side effect');

packages/node-resolve/test/snapshots/test.js.md

@@ -47,6 +47,23 @@ Generated by [AVA](https://avajs.dev).
       },
     ]
 
+## ignores the package.json sideEffects property for files in root package with "ignoreSideEffectsForRoot" option
+
+> Snapshot 1
+
+    `'use strict';␊
+    ␊
+    console.log('side effect');␊
+    `
+
+## respects the package.json sideEffects property for files in root package by default
+
+> Snapshot 1
+
+    `'use strict';␊
+    ␊
+    `
+
 ## throws error for removed customResolveOptions.basedir option
 
 > Snapshot 1

packages/node-resolve/test/test.js

@@ -246,6 +246,37 @@ test('resolves dynamic imports', async (t) => {
   t.is(result.default, 42);
 });
 
+test('respects the package.json sideEffects property for files in root package by default', async (t) => {
+  const bundle = await rollup({
+    input: 'root-package-side-effect/index.js',
+    plugins: [
+      nodeResolve({
+        rootDir: 'root-package-side-effect'
+      })
+    ]
+  });
+
+  const code = await getCode(bundle);
+  t.false(code.includes('side effect'));
+  t.snapshot(code);
+});
+
+test('ignores the package.json sideEffects property for files in root package with "ignoreSideEffectsForRoot" option', async (t) => {
+  const bundle = await rollup({
+    input: 'root-package-side-effect/index.js',
+    plugins: [
+      nodeResolve({
+        rootDir: 'root-package-side-effect',
+        ignoreSideEffectsForRoot: true
+      })
+    ]
+  });
+
+  const code = await getCode(bundle);
+  t.true(code.includes('side effect'));
+  t.snapshot(code);
+});
+
 test('handles package side-effects', async (t) => {
   const bundle = await rollup({
     input: 'side-effects.js',