Build: Add `exports` to package.json, export slim & esm builds

Summary of the changes:
* define the `exports` field in `package.json`; `jQuery` & `$` are also
  exported as named exports in ESM builds now
* declare `"type": "module"` globally except for the `build` folder
* add the `--esm` option to `grunt custom`, generating jQuery as an ECMAScript
  module into the `dist-module` folder
* expand `node_smoke_tests` to test the slim & ESM builds and their various
  combinations; also, test both jQuery loaded via a path to the file as well
  as from module specifiers that should be parsed via the `exports` feature
* add details about ESM usage to the release package README
* run `compare_size` on all built minified files; don't run it anymore on
  unminified files where they don't provide lots of value
* remove the remove_map_comment task; SWC doesn't insert the
`//# sourceMappingURL=` pragma by default so there's nothing to strip

Fixes gh-4592
Closes gh-5255

1 files changed, 0 insertions, 439 deletions

diff --git a/Gruntfile.js b/Gruntfile.js
deleted file mode 100644
index 11260d350..000000000
--- a/Gruntfile.js
+++ /dev/null
@@ -1,439 +0,0 @@
-"use strict";
-
-module.exports = function( grunt ) {
-	function readOptionalJSON( filepath ) {
-		const stripJSONComments = require( "strip-json-comments" );
-		let data = {};
-		try {
-			data = JSON.parse( stripJSONComments(
-				fs.readFileSync( filepath, { encoding: "utf8" } )
-			) );
-		} catch ( e ) {}
-		return data;
-	}
-
-	const fs = require( "fs" );
-	const gzip = require( "gzip-js" );
-	const nodeV14OrNewer = !/^v1[0-3]\./.test( process.version );
-	const nodeV17OrNewer = !/^v1[0-6]\./.test( process.version );
-	const customBrowsers = process.env.BROWSERS && process.env.BROWSERS.split( "," );
-
-	// Support: Node.js <14
-	// Skip running tasks that dropped support for Node.js 10 or 12
-	// in this Node version.
-	function runIfNewNode( task ) {
-		return nodeV14OrNewer ? task : "print_old_node_message:" + task;
-	}
-
-	if ( nodeV14OrNewer ) {
-		const playwright = require( "playwright-webkit" );
-		process.env.WEBKIT_HEADLESS_BIN = playwright.webkit.executablePath();
-	}
-
-	if ( !grunt.option( "filename" ) ) {
-		grunt.option( "filename", "jquery.js" );
-	}
-
-	grunt.initConfig( {
-		pkg: grunt.file.readJSON( "package.json" ),
-		dst: readOptionalJSON( "dist/.destination.json" ),
-		compare_size: {
-			files: [ "dist/jquery.js", "dist/jquery.min.js" ],
-			options: {
-				compress: {
-					gz: function( contents ) {
-						return gzip.zip( contents, {} ).length;
-					}
-				},
-				cache: "build/.sizecache.json"
-			}
-		},
-		babel: {
-			options: {
-				sourceMap: "inline",
-				retainLines: true,
-				plugins: [ "@babel/transform-for-of" ]
-			},
-			tests: {
-				files: {
-					"test/data/core/jquery-iterability-transpiled.js":
-						"test/data/core/jquery-iterability-transpiled-es6.js"
-				}
-			}
-		},
-		build: {
-			all: {
-				dest: "dist/jquery.js",
-				minimum: [
-					"core"
-				],
-
-				// Exclude specified modules if the module matching the key is removed
-				removeWith: {
-					ajax: [ "manipulation/_evalUrl", "deprecated/ajax-event-alias" ],
-					callbacks: [ "deferred" ],
-					css: [ "effects", "dimensions", "offset" ],
-					"css/showHide": [ "effects" ],
-					deferred: {
-						remove: [ "ajax", "effects", "queue", "core/ready" ],
-						include: [ "core/ready-no-deferred" ]
-					},
-					event: [ "deprecated/ajax-event-alias", "deprecated/event" ],
-					selector: [ "css/hiddenVisibleSelectors", "effects/animatedSelector" ]
-				}
-			}
-		},
-		npmcopy: {
-			all: {
-				options: {
-					destPrefix: "external"
-				},
-				files: {
-					"bootstrap/bootstrap.css": "bootstrap/dist/css/bootstrap.css",
-					"bootstrap/bootstrap.min.css": "bootstrap/dist/css/bootstrap.min.css",
-					"bootstrap/bootstrap.min.css.map": "bootstrap/dist/css/bootstrap.min.css.map",
-
-					"core-js-bundle/core-js-bundle.js": "core-js-bundle/minified.js",
-					"core-js-bundle/LICENSE": "core-js-bundle/LICENSE",
-
-					"npo/npo.js": "native-promise-only/lib/npo.src.js",
-
-					"qunit/qunit.js": "qunit/qunit/qunit.js",
-					"qunit/qunit.css": "qunit/qunit/qunit.css",
-					"qunit/LICENSE.txt": "qunit/LICENSE.txt",
-
-					"requirejs/require.js": "requirejs/require.js",
-
-					"sinon/sinon.js": "sinon/pkg/sinon.js",
-					"sinon/LICENSE.txt": "sinon/LICENSE"
-				}
-			}
-		},
-		jsonlint: {
-			pkg: {
-				src: [ "package.json" ]
-			}
-		},
-		eslint: {
-			options: {
-				maxWarnings: 0
-			},
-
-			// We have to explicitly declare "src" property otherwise "newer"
-			// task wouldn't work properly :/
-			dist: {
-				src: [ "dist/jquery.js", "dist/jquery.min.js" ]
-			},
-			dev: {
-				src: [
-					"src/**/*.js",
-					"Gruntfile.js",
-					"test/**/*.js",
-					"build/**/*.js",
-
-					// Ignore files from .eslintignore
-					// See https://github.com/sindresorhus/grunt-eslint/issues/119
-					...fs
-						.readFileSync( `${ __dirname }/.eslintignore`, "utf-8" )
-						.split( "\n" )
-						.filter( filePath => filePath )
-						.map( filePath => filePath[ 0 ] === "!" ?
-							filePath.slice( 1 ) :
-							`!${ filePath }`
-						),
-
-					// Explicitly ignore `dist/` as it could be unignored by
-					// the above `.eslintignore` parsing.
-					"!dist/**/*.js"
-				]
-			}
-		},
-		testswarm: {
-			tests: [
-
-				// A special module with basic tests, meant for not fully
-				// supported environments like jsdom. We run it everywhere,
-				// though, to make sure tests are not broken.
-				"basic",
-
-				"ajax",
-				"animation",
-				"attributes",
-				"callbacks",
-				"core",
-				"css",
-				"data",
-				"deferred",
-				"deprecated",
-				"dimensions",
-				"effects",
-				"event",
-				"manipulation",
-				"offset",
-				"queue",
-				"selector",
-				"serialize",
-				"support",
-				"traversing",
-				"tween"
-			]
-		},
-		karma: {
-			options: {
-				customContextFile: "test/karma.context.html",
-				customDebugFile: "test/karma.debug.html",
-				customLaunchers: {
-					ChromeHeadlessNoSandbox: {
-						base: "ChromeHeadless",
-						flags: [ "--no-sandbox" ]
-					}
-				},
-				frameworks: [ "qunit" ],
-				middleware: [ "mockserver" ],
-				plugins: [
-					"karma-*",
-					{
-						"middleware:mockserver": [
-							"factory",
-							require( "./test/middleware-mockserver.js" )
-						]
-					}
-				],
-				client: {
-					qunit: {
-
-						// We're running `QUnit.start()` ourselves via `loadTests()`
-						// in test/jquery.js
-						autostart: false
-					}
-				},
-				files: [
-					"test/data/jquery-1.9.1.js",
-					"external/sinon/sinon.js",
-					"external/npo/npo.js",
-					"external/requirejs/require.js",
-					"test/data/testinit.js",
-
-					"test/jquery.js",
-
-					{
-						pattern: "dist/jquery.*",
-						included: false,
-						served: true,
-						nocache: true
-					},
-					{
-						pattern: "src/**",
-						type: "module",
-						included: false,
-						served: true,
-						nocache: true
-					},
-					{ pattern: "external/**", included: false, served: true },
-					{
-						pattern: "test/**/*.@(js|css|jpg|html|xml|svg)",
-						included: false,
-						served: true,
-						nocache: true
-					}
-				],
-				reporters: [ "dots" ],
-				autoWatch: false,
-
-				// 2 minutes; has to be longer than QUnit.config.testTimeout
-				browserNoActivityTimeout: 120e3,
-
-				concurrency: 3,
-				captureTimeout: 20 * 1000,
-				singleRun: true
-			},
-			main: {
-				browsers: customBrowsers ||
-					[ "ChromeHeadless", "FirefoxHeadless", "WebkitHeadless" ]
-			},
-			esmodules: {
-				browsers: customBrowsers || [ "ChromeHeadless" ],
-				options: {
-					client: {
-						qunit: {
-
-							// We're running `QUnit.start()` ourselves via `loadTests()`
-							// in test/jquery.js
-							autostart: false,
-
-							esmodules: true
-						}
-					}
-				}
-			},
-
-			jsdom: {
-				options: {
-					files: [
-						"test/data/jquery-1.9.1.js",
-						"test/data/testinit-jsdom.js",
-
-						// We don't support various loading methods like esmodules,
-						// choosing a version etc. for jsdom.
-						"dist/jquery.js",
-
-						// A partial replacement for testinit.js#loadTests()
-						"test/data/testrunner.js",
-
-						// jsdom only runs basic tests
-						"test/unit/basic.js",
-
-						{
-							pattern: "test/**/*.@(js|css|jpg|html|xml|svg)",
-							included: false,
-							served: true
-						}
-					]
-				},
-				browsers: [ "jsdom" ]
-			},
-
-			// To debug tests with Karma:
-			// 1. Run 'grunt karma:chrome-debug' or 'grunt karma:firefox-debug'
-			//    (any karma subtask that has singleRun=false)
-			// 2. Press "Debug" in the opened browser window to start
-			//    the tests. Unlike the other karma tasks, the debug task will
-			//    keep the browser window open.
-			"chrome-debug": {
-				browsers: [ "Chrome" ],
-				singleRun: false
-			},
-			"firefox-debug": {
-				browsers: [ "Firefox" ],
-				singleRun: false
-			},
-			"ie-debug": {
-				browsers: [ "IE" ],
-				singleRun: false
-			}
-		},
-		watch: {
-			files: [ "<%= eslint.dev.src %>" ],
-			tasks: [ "dev" ]
-		},
-		minify: {
-			all: {
-				files: {
-					"dist/<%= grunt.option('filename').replace('.js', '.min.js') %>":
-						"dist/<%= grunt.option('filename') %>"
-				},
-				options: {
-					sourceMap: {
-						filename: "dist/<%= grunt.option('filename').replace('.js', '.min.map') %>",
-
-						// The map's `files` & `sources` property are set incorrectly, fix
-						// them via overrides from the task config.
-						// See https://github.com/swc-project/swc/issues/7588#issuecomment-1624345254
-						overrides: {
-							file: "jquery.min.js",
-							sources: [
-								"jquery.js"
-							]
-						}
-					},
-					swc: {
-						format: {
-							ecma: 5,
-							asciiOnly: true,
-							comments: false,
-							preamble: "/*! jQuery v4.0.0-pre | " +
-								"(c) OpenJS Foundation and other contributors | " +
-								"jquery.org/license */\n"
-						},
-						compress: {
-							ecma: 5,
-							hoist_funs: false,
-							loops: false
-						},
-						mangle: true
-					}
-				}
-			}
-		}
-	} );
-
-	// Load grunt tasks from NPM packages
-	require( "load-grunt-tasks" )( grunt, {
-		pattern: nodeV14OrNewer ? [ "grunt-*" ] : [ "grunt-*", "!grunt-eslint" ]
-	} );
-
-	// Integrate jQuery specific tasks
-	grunt.loadTasks( "build/tasks" );
-
-	grunt.registerTask( "print_old_node_message", ( ...args ) => {
-		var task = args.join( ":" );
-		grunt.log.writeln( "Old Node.js detected, running the task \"" + task + "\" skipped..." );
-	} );
-
-	grunt.registerTask( "print_jsdom_message", () => {
-		grunt.log.writeln( "Node.js 17 or newer detected, skipping jsdom tests..." );
-	} );
-
-	grunt.registerTask( "lint", [
-		"jsonlint",
-
-		// Running the full eslint task without breaking it down to targets
-		// would run the dist target first which would point to errors in the built
-		// file, making it harder to fix them. We want to check the built file only
-		// if we already know the source files pass the linter.
-		runIfNewNode( "eslint:dev" ),
-		runIfNewNode( "eslint:dist" )
-	] );
-
-	grunt.registerTask( "lint:newer", [
-		"newer:jsonlint",
-
-		// Don't replace it with just the task; see the above comment.
-		runIfNewNode( "newer:eslint:dev" ),
-		runIfNewNode( "newer:eslint:dist" )
-	] );
-
-	grunt.registerTask( "test:fast", runIfNewNode( "node_smoke_tests" ) );
-	grunt.registerTask( "test:slow", [
-		runIfNewNode( "promises_aplus_tests" ),
-
-		// Support: Node.js 17+
-		// jsdom fails to connect to the Karma server in Node 17+.
-		// Until we figure out a fix, skip jsdom tests there.
-		nodeV17OrNewer ? "print_jsdom_message" : runIfNewNode( "karma:jsdom" )
-	] );
-
-	grunt.registerTask( "test:prepare", [
-		"npmcopy",
-		"qunit_fixture",
-		"babel:tests"
-	] );
-
-	grunt.registerTask( "test", [
-		"test:prepare",
-		"test:fast",
-		"test:slow"
-	] );
-
-	grunt.registerTask( "dev", [
-		"build:*:*",
-		runIfNewNode( "newer:eslint:dev" ),
-		"newer:minify",
-		"remove_map_comment",
-		"dist:*",
-		"qunit_fixture",
-		"compare_size"
-	] );
-
-	grunt.registerTask( "default", [
-		runIfNewNode( "eslint:dev" ),
-		"build:*:*",
-		"minify",
-		"remove_map_comment",
-		"dist:*",
-		"test:prepare",
-		runIfNewNode( "eslint:dist" ),
-		"test:fast",
-		"compare_size"
-	] );
-};