esbuild/internal/bundler/bundler_packagejson_test.go

package bundler

import (
	"testing"

	"github.com/evanw/esbuild/internal/config"
)

var packagejson_suite = suite{
	name: "packagejson",
}

func TestPackageJsonMain(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./custom-main.js"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/custom-main.js": `
				module.exports = function() {
					return 123
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBadMain(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./does-not-exist.js"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/index.js": `
				module.exports = function() {
					return 123
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonSyntaxErrorComment(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					// Single-line comment
					"a": 1
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/index.js": `
				module.exports = function() {
					return 123
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
		expectedScanLog: "/Users/user/project/node_modules/demo-pkg/package.json: error: JSON does not support comments\n",
	})
}

func TestPackageJsonSyntaxErrorTrailingComma(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"a": 1,
					"b": 2,
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/index.js": `
				module.exports = function() {
					return 123
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
		expectedScanLog: "/Users/user/project/node_modules/demo-pkg/package.json: error: JSON does not support trailing commas\n",
	})
}

func TestPackageJsonModule(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main.js",
					"module": "./main.esm.js"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				module.exports = function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.esm.js": `
				export default function() {
					return 123
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserString(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"browser": "./browser"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/browser.js": `
				module.exports = function() {
					return 123
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserMapRelativeToRelative(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main",
					"browser": {
						"./main.js": "./main-browser",
						"./lib/util.js": "./lib/util-browser"
					}
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				const util = require('./lib/util')
				module.exports = function() {
					return ['main', util]
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main-browser.js": `
				const util = require('./lib/util')
				module.exports = function() {
					return ['main-browser', util]
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/lib/util.js": `
				module.exports = 'util'
			`,
			"/Users/user/project/node_modules/demo-pkg/lib/util-browser.js": `
				module.exports = 'util-browser'
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserMapRelativeToModule(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main",
					"browser": {
						"./util.js": "util-browser"
					}
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				const util = require('./util')
				module.exports = function() {
					return ['main', util]
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/util.js": `
				module.exports = 'util'
			`,
			"/Users/user/project/node_modules/util-browser/index.js": `
				module.exports = 'util-browser'
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserMapRelativeDisabled(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main",
					"browser": {
						"./util-node.js": false
					}
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				const util = require('./util-node')
				module.exports = function(obj) {
					return util.inspect(obj)
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/util-node.js": `
				module.exports = require('util')
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserMapModuleToRelative(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"browser": {
						"node-pkg": "./node-pkg-browser"
					}
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/node-pkg-browser.js": `
				module.exports = function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/index.js": `
				const fn = require('node-pkg')
				module.exports = function() {
					return fn()
				}
			`,
			"/Users/user/project/node_modules/node-pkg/index.js": `
				module.exports = function() {
					return 234
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserMapModuleToModule(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"browser": {
						"node-pkg": "node-pkg-browser"
					}
				}
			`,
			"/Users/user/project/node_modules/node-pkg-browser/index.js": `
				module.exports = function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/index.js": `
				const fn = require('node-pkg')
				module.exports = function() {
					return fn()
				}
			`,
			"/Users/user/project/node_modules/node-pkg/index.js": `
				module.exports = function() {
					return 234
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserMapModuleDisabled(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"browser": {
						"node-pkg": false
					}
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/index.js": `
				const fn = require('node-pkg')
				module.exports = function() {
					return fn()
				}
			`,
			"/Users/user/project/node_modules/node-pkg/index.js": `
				module.exports = function() {
					return 234
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserMapNativeModuleDisabled(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"browser": {
						"fs": false
					}
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/index.js": `
				const fs = require('fs')
				module.exports = function() {
					return fs.readFile()
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserMapAvoidMissing(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import 'component-classes'
			`,
			"/Users/user/project/node_modules/component-classes/package.json": `
				{
					"browser": {
						"indexof": "component-indexof"
					}
				}
			`,
			"/Users/user/project/node_modules/component-classes/index.js": `
				try {
					var index = require('indexof');
				} catch (err) {
					var index = require('component-indexof');
				}
			`,
			"/Users/user/project/node_modules/component-indexof/index.js": `
				module.exports = function() {
					return 234
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserOverModuleBrowser(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main.js",
					"module": "./main.esm.js",
					"browser": "./main.browser.js"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				module.exports = function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.esm.js": `
				export default function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.browser.js": `
				module.exports = function() {
					return 123
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			Platform:      config.PlatformBrowser,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserOverMainNode(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main.js",
					"module": "./main.esm.js",
					"browser": "./main.browser.js"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				module.exports = function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.esm.js": `
				export default function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.browser.js": `
				module.exports = function() {
					return 123
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			Platform:      config.PlatformNode,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserWithModuleBrowser(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main.js",
					"module": "./main.esm.js",
					"browser": {
						"./main.js": "./main.browser.js",
						"./main.esm.js": "./main.browser.esm.js"
					}
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				module.exports = function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.esm.js": `
				export default function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.browser.js": `
				module.exports = function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.browser.esm.js": `
				export default function() {
					return 123
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			Platform:      config.PlatformBrowser,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonBrowserWithMainNode(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import fn from 'demo-pkg'
				console.log(fn())
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main.js",
					"module": "./main.esm.js",
					"browser": {
						"./main.js": "./main.browser.js",
						"./main.esm.js": "./main.browser.esm.js"
					}
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				module.exports = function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.esm.js": `
				export default function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.browser.js": `
				module.exports = function() {
					return 123
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.browser.esm.js": `
				export default function() {
					return 123
				}
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			Platform:      config.PlatformNode,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonDualPackageHazardImportOnly(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import value from 'demo-pkg'
				console.log(value)
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main.js",
					"module": "./module.js"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				module.exports = 'main'
			`,
			"/Users/user/project/node_modules/demo-pkg/module.js": `
				export default 'module'
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonDualPackageHazardRequireOnly(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				console.log(require('demo-pkg'))
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main.js",
					"module": "./module.js"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				module.exports = 'main'
			`,
			"/Users/user/project/node_modules/demo-pkg/module.js": `
				export default 'module'
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonDualPackageHazardImportAndRequireSameFile(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import value from 'demo-pkg'
				console.log(value, require('demo-pkg'))
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main.js",
					"module": "./module.js"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				module.exports = 'main'
			`,
			"/Users/user/project/node_modules/demo-pkg/module.js": `
				export default 'module'
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonDualPackageHazardImportAndRequireSeparateFiles(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import './test-main'
				import './test-module'
			`,
			"/Users/user/project/src/test-main.js": `
				console.log(require('demo-pkg'))
			`,
			"/Users/user/project/src/test-module.js": `
				import value from 'demo-pkg'
				console.log(value)
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main.js",
					"module": "./module.js"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				module.exports = 'main'
			`,
			"/Users/user/project/node_modules/demo-pkg/module.js": `
				export default 'module'
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonDualPackageHazardImportAndRequireForceModuleBeforeMain(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import './test-main'
				import './test-module'
			`,
			"/Users/user/project/src/test-main.js": `
				console.log(require('demo-pkg'))
			`,
			"/Users/user/project/src/test-module.js": `
				import value from 'demo-pkg'
				console.log(value)
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main.js",
					"module": "./module.js"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				module.exports = 'main'
			`,
			"/Users/user/project/node_modules/demo-pkg/module.js": `
				export default 'module'
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			MainFields:    []string{"module", "main"},
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonDualPackageHazardImportAndRequireBrowser(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import './test-main'
				import './test-module'
			`,
			"/Users/user/project/src/test-main.js": `
				console.log(require('demo-pkg'))
			`,
			"/Users/user/project/src/test-module.js": `
				import value from 'demo-pkg'
				console.log(value)
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"main": "./main.js",
					"module": "./module.js",
					"browser": {
						"./main.js": "./main.browser.js",
						"./module.js": "./module.browser.js"
					}
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/main.js": `
				module.exports = 'main'
			`,
			"/Users/user/project/node_modules/demo-pkg/module.js": `
				export default 'module'
			`,
			"/Users/user/project/node_modules/demo-pkg/main.browser.js": `
				module.exports = 'browser main'
			`,
			"/Users/user/project/node_modules/demo-pkg/module.browser.js": `
				export default 'browser module'
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonMainFieldsA(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import value from 'demo-pkg'
				console.log(value)
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"a": "./a.js",
					"b": "./b.js"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/a.js": `
				module.exports = 'a'
			`,
			"/Users/user/project/node_modules/demo-pkg/b.js": `
				export default 'b'
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			MainFields:    []string{"a", "b"},
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}

func TestPackageJsonMainFieldsB(t *testing.T) {
	packagejson_suite.expectBundled(t, bundled{
		files: map[string]string{
			"/Users/user/project/src/entry.js": `
				import value from 'demo-pkg'
				console.log(value)
			`,
			"/Users/user/project/node_modules/demo-pkg/package.json": `
				{
					"a": "./a.js",
					"b": "./b.js"
				}
			`,
			"/Users/user/project/node_modules/demo-pkg/a.js": `
				module.exports = 'a'
			`,
			"/Users/user/project/node_modules/demo-pkg/b.js": `
				export default 'b'
			`,
		},
		entryPaths: []string{"/Users/user/project/src/entry.js"},
		options: config.Options{
			Mode:          config.ModeBundle,
			MainFields:    []string{"b", "a"},
			AbsOutputFile: "/Users/user/project/out.js",
		},
	})
}