Fix ordering of jsnext:main when using the jsnext option

package.json

@@ -6,13 +6,12 @@
     "buble": "^0.19.7",
     "es5-ext": "^0.10.49",
     "eslint": "^5.16.0",
-    "mocha": "^6.0.2",
-    "rollup": "^1.8.0",
+    "mocha": "^6.1.2",
+    "rollup": "^1.9.3",
     "rollup-plugin-buble": "^0.19.6",
     "rollup-plugin-commonjs": "^9.3.4",
     "string-capitalize": "^1.0.1",
-    "typescript": "^3.4.1",
-    "vlq": "^1.0.0"
+    "typescript": "^3.4.3"
   },
   "main": "dist/rollup-plugin-node-resolve.cjs.js",
   "module": "dist/rollup-plugin-node-resolve.es.js",
@@ -33,7 +32,7 @@
   ],
   "dependencies": {
     "@types/resolve": "0.0.8",
-    "builtin-modules": "^3.0.0",
+    "builtin-modules": "^3.1.0",
     "is-module": "^1.0.0",
     "resolve": "^1.10.0"
   },

src/index.js

@@ -1,4 +1,4 @@
-import {dirname, extname, normalize, resolve, sep, join} from 'path';
+import {dirname, extname, join, normalize, resolve, sep} from 'path';
 import builtins from 'builtin-modules';
 import resolveId from 'resolve';
 import isModule from 'is-module';
@@ -45,16 +45,16 @@ function getMainFields (options) {
 		}
 		mainFields = options.mainFields;
 	} else {
-		mainFields = ['module', 'main'];
-		[['module', 'module'], ['jsnext', 'jsnext:main'], ['main', 'main']].forEach(([option, field]) => {
+		mainFields = [];
+		[['module', 'module', true], ['jsnext', 'jsnext:main', false], ['main', 'main', true]].forEach(([option, field, defaultIncluded]) => {
 			if (option in options) {
 				// eslint-disable-next-line no-console
 				console.warn(`node-resolve: setting options.${option} is deprecated, please override options.mainFields instead`);
-				if (options[option] === false) {
-					mainFields = mainFields.filter(mainField => mainField !== field);
-				} else if (options[option] === true && mainFields.indexOf(field) === -1) {
+				if (options[option]) {
 					mainFields.push(field);
 				}
+			} else if (defaultIncluded) {
+				mainFields.push(field);
 			}
 		});
 	}

test/samples/jsnext/main.js

@@ -1,3 +1,3 @@
-import { encode } from 'vlq';
+import value from 'jsnext';
 
-export default encode( 123 ); // 2H
+export default value;

test/test.js

@@ -58,18 +58,29 @@ describe( 'rollup-plugin-node-resolve', function () {
 				nodeResolve({ mainFields: ['jsnext:main', 'module', 'main'] })
 			]
 		}).then( executeBundle ).then( module => {
-			assert.equal( module.exports, '2H' );
+			assert.equal( module.exports, 'JSNEXT' );
 		});
 	});
 
-	it( 'DEPRECATED: options.jsnext still works', function () {
+	it( 'DEPRECATED: options.jsnext still works with correct priority', function () {
 		return rollup.rollup({
 			input: 'samples/jsnext/main.js',
 			plugins: [
-				nodeResolve({ jsnext: true })
+				nodeResolve({ jsnext: true, main: true })
 			]
 		}).then( executeBundle ).then( module => {
-			assert.equal( module.exports, '2H' );
+			assert.equal( module.exports, 'JSNEXT' );
+		});
+	});
+
+	it( 'DEPRECATED: options.module still works with correct priority', function () {
+		return rollup.rollup({
+			input: 'samples/module/main.js',
+			plugins: [
+				nodeResolve({ module: true, main: true, preferBuiltins: false })
+			]
+		}).then( executeBundle ).then( module => {
+			assert.equal( module.exports, 'MODULE' );
 		});
 	});
 
@@ -660,7 +671,7 @@ describe( 'rollup-plugin-node-resolve', function () {
 				nodeResolve({})
 			]
 		}).then( executeBundle ).then( module => {
-			assert.equal( module.exports, '2H' );
+			assert.equal( module.exports, 'MAIN' );
 		});
 	});
 
@@ -819,7 +830,7 @@ describe( 'rollup-plugin-node-resolve', function () {
 				})
 			]
 		}).then( executeBundle ).then( module => {
-			assert.deepEqual(module.exports, { 
+			assert.deepEqual(module.exports, {
 				React: 'react:root',
 				ReactConsumer: 'react-consumer:react:root'
 			});
@@ -833,7 +844,7 @@ describe( 'rollup-plugin-node-resolve', function () {
 				nodeResolve()
 			]
 		}).then( executeBundle ).then( module => {
-			assert.deepEqual(module.exports, { 
+			assert.deepEqual(module.exports, {
 				React: 'react:root',
 				ReactConsumer: 'react-consumer:react:child'
 			});