Merge pull request #11137 from webpack/change/dev-no-used

disable used exports optimization in development

lib/config/defaults.js

@@ -550,8 +550,8 @@ const applyOptimizationDefaults = (
 	});
 	D(optimization, "sideEffects", true);
 	D(optimization, "providedExports", true);
-	D(optimization, "usedExports", true);
-	D(optimization, "innerGraph", true);
+	D(optimization, "usedExports", production);
+	D(optimization, "innerGraph", production);
 	D(optimization, "mangleExports", production);
 	D(optimization, "concatenateModules", production);
 	D(optimization, "runtimeChunk", false);

lib/dependencies/ExportsInfoDependency.js

@@ -29,8 +29,13 @@ const getProperty = (moduleGraph, module, exportName, property) => {
 		switch (property) {
 			case "usedExports": {
 				const usedExports = moduleGraph.getExportsInfo(module).getUsedExports();
-				if (typeof usedExports === "boolean" || usedExports === undefined)
+				if (
+					typeof usedExports === "boolean" ||
+					usedExports === undefined ||
+					usedExports === null
+				) {
 					return usedExports;
+				}
 				return Array.from(usedExports).sort();
 			}
 		}

test/Defaults.unittest.js

@@ -148,7 +148,7 @@ describe("Defaults", () => {
 		    "chunkIds": "natural",
 		    "concatenateModules": false,
 		    "flagIncludedChunks": false,
-		    "innerGraph": true,
+		    "innerGraph": false,
 		    "mangleExports": false,
 		    "mangleWasmImports": false,
 		    "mergeDuplicateChunks": true,
@@ -191,7 +191,7 @@ describe("Defaults", () => {
 		      "minRemainingSize": undefined,
 		      "minSize": 10000,
 		    },
-		    "usedExports": true,
+		    "usedExports": false,
 		  },
 		  "output": Object {
 		    "assetModuleFilename": "[hash][ext]",
@@ -357,12 +357,13 @@ describe("Defaults", () => {
 		-     "chunkIds": "natural",
 		-     "concatenateModules": false,
 		-     "flagIncludedChunks": false,
+		-     "innerGraph": false,
+		-     "mangleExports": false,
 		+     "checkWasmTypes": true,
 		+     "chunkIds": "deterministic",
 		+     "concatenateModules": true,
 		+     "flagIncludedChunks": true,
-		@@ ... @@
-		-     "mangleExports": false,
+		+     "innerGraph": true,
 		+     "mangleExports": true,
 		@@ ... @@
 		-     "minimize": false,
@@ -385,6 +386,9 @@ describe("Defaults", () => {
 		-       "minSize": 10000,
 		+       "minSize": 30000,
 		@@ ... @@
+		-     "usedExports": false,
+		+     "usedExports": true,
+		@@ ... @@
 		-   "performance": false,
 		+   "performance": Object {
 		+     "hints": "warning",
@@ -406,12 +410,13 @@ describe("Defaults", () => {
 		-     "chunkIds": "natural",
 		-     "concatenateModules": false,
 		-     "flagIncludedChunks": false,
+		-     "innerGraph": false,
+		-     "mangleExports": false,
 		+     "checkWasmTypes": true,
 		+     "chunkIds": "deterministic",
 		+     "concatenateModules": true,
 		+     "flagIncludedChunks": true,
-		@@ ... @@
-		-     "mangleExports": false,
+		+     "innerGraph": true,
 		+     "mangleExports": true,
 		@@ ... @@
 		-     "minimize": false,
@@ -434,6 +439,9 @@ describe("Defaults", () => {
 		-       "minSize": 10000,
 		+       "minSize": 30000,
 		@@ ... @@
+		-     "usedExports": false,
+		+     "usedExports": true,
+		@@ ... @@
 		-   "performance": false,
 		+   "performance": Object {
 		+     "hints": "warning",

test/__snapshots__/StatsTestCases.test.js.snap

@@ -447,29 +447,31 @@ Child all:
 `;
 
 exports[`StatsTestCases should print correct stats for chunk-module-id-range 1`] = `
-"Hash: f33d111f25cd01c8c3cf
+"Hash: 024b7b1350be3708ba8e
 Time: X ms
 Built at: 1970-04-20 12:42:42
 PublicPath: (none)
-   Asset     Size
-main1.js  1.9 KiB  [emitted]  [name: main1]
-main2.js  1.9 KiB  [emitted]  [name: main2]
+   Asset      Size
+main1.js  4.39 KiB  [emitted]  [name: main1]
+main2.js  4.38 KiB  [emitted]  [name: main2]
 Entrypoint main1 = main1.js
 Entrypoint main2 = main2.js
-chunk main2.js (main2) 136 bytes [entry] [rendered]
+chunk main2.js (main2) 136 bytes (javascript) 668 bytes (runtime) [entry] [rendered]
     > ./main2 main2
  ./a.js 20 bytes [built]
  ./d.js 20 bytes [built]
  ./e.js 20 bytes [built]
  ./f.js 20 bytes [built]
  ./main2.js 56 bytes [built]
-chunk main1.js (main1) 136 bytes [entry] [rendered]
+     + 3 hidden chunk modules
+chunk main1.js (main1) 136 bytes (javascript) 668 bytes (runtime) [entry] [rendered]
     > ./main1 main1
  ./a.js 20 bytes [built]
  ./b.js 20 bytes [built]
  ./c.js 20 bytes [built]
  ./d.js 20 bytes [built]
- ./main1.js 56 bytes [built]"
+ ./main1.js 56 bytes [built]
+     + 3 hidden chunk modules"
 `;
 
 exports[`StatsTestCases should print correct stats for chunks 1`] = `
@@ -3568,10 +3570,10 @@ Child development:
     chunk dev-main-very-big_js-4647fb9d.js (main-very-big_js-4647fb9d) 1.57 KiB ={main-big_js-1}= ={main-in-some-directory_b}= ={main-in-some-directory_very-big_js-8d76cf03}= ={main-index_js-41f5a26e}= ={main-inner-module_small_js-3}= ={main-small_js-1}= ={main-subfolder_big_js-b}= ={main-subfolder_small_js-1}= ={main-very-big_js-08cf55cf}= ={main-very-big_js-62f7f644}= ={vendors-node_modules_big_js_1-node_modules_small_js_1-node_modules_small_js_2}= ={vendors-node_modules_very-big_js_1}= [initial] [rendered]
         > ./ main
      ./very-big.js?3 1.57 KiB [built]
-    chunk dev-main-very-big_js-62f7f644.js (main-very-big_js-62f7f644) 1.57 KiB (javascript) 4.84 KiB (runtime) ={main-big_js-1}= ={main-in-some-directory_b}= ={main-in-some-directory_very-big_js-8d76cf03}= ={main-index_js-41f5a26e}= ={main-inner-module_small_js-3}= ={main-small_js-1}= ={main-subfolder_big_js-b}= ={main-subfolder_small_js-1}= ={main-very-big_js-08cf55cf}= ={main-very-big_js-4647fb9d}= ={vendors-node_modules_big_js_1-node_modules_small_js_1-node_modules_small_js_2}= ={vendors-node_modules_very-big_js_1}= [entry] [rendered]
+    chunk dev-main-very-big_js-62f7f644.js (main-very-big_js-62f7f644) 1.57 KiB (javascript) 5.11 KiB (runtime) ={main-big_js-1}= ={main-in-some-directory_b}= ={main-in-some-directory_very-big_js-8d76cf03}= ={main-index_js-41f5a26e}= ={main-inner-module_small_js-3}= ={main-small_js-1}= ={main-subfolder_big_js-b}= ={main-subfolder_small_js-1}= ={main-very-big_js-08cf55cf}= ={main-very-big_js-4647fb9d}= ={vendors-node_modules_big_js_1-node_modules_small_js_1-node_modules_small_js_2}= ={vendors-node_modules_very-big_js_1}= [entry] [rendered]
         > ./ main
      ./very-big.js?1 1.57 KiB [built]
-         + 5 hidden root modules
+         + 6 hidden root modules
     chunk dev-vendors-node_modules_big_js_1-node_modules_small_js_1-node_modules_small_js_2.js (id hint: vendors) 402 bytes ={main-big_js-1}= ={main-in-some-directory_b}= ={main-in-some-directory_very-big_js-8d76cf03}= ={main-index_js-41f5a26e}= ={main-inner-module_small_js-3}= ={main-small_js-1}= ={main-subfolder_big_js-b}= ={main-subfolder_small_js-1}= ={main-very-big_js-08cf55cf}= ={main-very-big_js-4647fb9d}= ={main-very-big_js-62f7f644}= ={vendors-node_modules_very-big_js_1}= [initial] [rendered] split chunk (cache group: defaultVendors)
         > ./ main
      ./node_modules/big.js?1 268 bytes [built]

test/cases/chunks/inline-options/index.js

@@ -116,67 +116,71 @@ it("should not find module when mode is weak and chunk not served elsewhere (wit
 	});
 });
 
-it("should contain only one export from webpackExports from module", function () {
-	return import(/* webpackExports: "usedExports" */ "./dir12/a?1").then(
-		module => {
-			expect(module.usedExports).toEqual(["usedExports"]);
-		}
-	);
-});
-
-it("should contain only webpackExports from module", function () {
-	return import(
-		/* webpackExports: ["a", "usedExports", "b"] */ "./dir12/a?2"
-	).then(module => {
-		expect(module.usedExports).toEqual(["a", "b", "usedExports"]);
+if (process.env.NODE_ENV === "production") {
+	it("should contain only one export from webpackExports from module", function () {
+		return import(/* webpackExports: "usedExports" */ "./dir12/a?1").then(
+			module => {
+				expect(module.usedExports).toEqual(["usedExports"]);
+			}
+		);
 	});
-});
 
-it("should contain only webpackExports from module in eager mode", function () {
-	return import(
-		/*
+	it("should contain only webpackExports from module", function () {
+		return import(
+			/* webpackExports: ["a", "usedExports", "b"] */ "./dir12/a?2"
+		).then(module => {
+			expect(module.usedExports).toEqual(["a", "b", "usedExports"]);
+		});
+	});
+
+	it("should contain only webpackExports from module in eager mode", function () {
+		return import(
+			/*
 			webpackMode: "eager",
 			webpackExports: ["a", "usedExports", "b"]
 		*/ "./dir12/a?3"
-	).then(module => {
-		expect(module.usedExports).toEqual(["a", "b", "usedExports"]);
+		).then(module => {
+			expect(module.usedExports).toEqual(["a", "b", "usedExports"]);
+		});
 	});
-});
 
-it("should contain webpackExports from module in weak mode", function () {
-	require.resolve("./dir12/a?4");
-	return import(
-		/*
+	it("should contain webpackExports from module in weak mode", function () {
+		require.resolve("./dir12/a?4");
+		return import(
+			/*
 			webpackMode: "weak",
 			webpackExports: ["a", "usedExports", "b"]
 		*/ "./dir12/a?4"
-	).then(module => {
-		expect(module.usedExports).toEqual(["a", "b", "usedExports"]);
+		).then(module => {
+			expect(module.usedExports).toEqual(["a", "b", "usedExports"]);
+		});
 	});
-});
 
-it("should not mangle webpackExports from module", function () {
-	return import(/* webpackExports: "longnameforexport" */ "./dir12/a?5").then(
-		module => {
-			expect(module).toHaveProperty("longnameforexport");
-		}
-	);
-});
-
-it("should not mangle default webpackExports from module", function () {
-	return import(/* webpackExports: "default" */ "./dir12/a?6").then(module => {
-		expect(module).toHaveProperty("default");
+	it("should not mangle webpackExports from module", function () {
+		return import(/* webpackExports: "longnameforexport" */ "./dir12/a?5").then(
+			module => {
+				expect(module).toHaveProperty("longnameforexport");
+			}
+		);
 	});
-});
 
-it("should contain only webpackExports from module in context mode", function () {
-	const x = "b";
-	return import(/* webpackExports: "usedExports" */ `./dir13/${x}`).then(
-		module => {
-			expect(module.usedExports).toEqual(["usedExports"]);
-		}
-	);
-});
+	it("should not mangle default webpackExports from module", function () {
+		return import(/* webpackExports: "default" */ "./dir12/a?6").then(
+			module => {
+				expect(module).toHaveProperty("default");
+			}
+		);
+	});
+
+	it("should contain only webpackExports from module in context mode", function () {
+		const x = "b";
+		return import(/* webpackExports: "usedExports" */ `./dir13/${x}`).then(
+			module => {
+				expect(module.usedExports).toEqual(["usedExports"]);
+			}
+		);
+	});
+}
 
 function testChunkLoading(load, expectedSyncInitial, expectedSyncRequested) {
 	var sync = false;

test/cases/inner-graph/circular/index.js

@@ -5,6 +5,8 @@ it("export should be unused when only unused functions use it", () => {
 	expect(y("a")).toBe("okBAA");
 	expect(exportAUsed).toBe(true);
 	expect(exportBUsed).toBe(true);
-	expect(exportCUsed).toBe(false);
+	if (process.env.NODE_ENV === "production") {
+		expect(exportCUsed).toBe(false);
+	}
 	return import("./chunk");
 });

test/cases/inner-graph/export-default-named/index.js

@@ -21,21 +21,25 @@ it("a should be used", () => {
 	expect(a).toBe(true);
 });
 
-it("b should be unused", () => {
-	expect(b).toBe(false);
-});
+if (process.env.NODE_ENV === "production") {
+	it("b should be unused", () => {
+		expect(b).toBe(false);
+	});
+}
 
 it("c should be used", () => {
 	expect(c).toBe(true);
 });
 
-it("d should be used", () => {
-	expect(d).toBe(true);
-});
+if (process.env.NODE_ENV === "production") {
+	it("d should be used", () => {
+		expect(d).toBe(true);
+	});
 
-it("e should be unused", () => {
-	expect(e).toBe(false);
-});
+	it("e should be unused", () => {
+		expect(e).toBe(false);
+	});
+}
 
 it("f should be used", () => {
 	expect(f).toBe(true);

test/cases/inner-graph/extend-class/index.js

@@ -14,9 +14,11 @@ it("should load modules correctly", () => {
 	require("./module2");
 });
 
-it("B should not be used", () => {
-	expect(exportsInfoForB).toBe(false);
-});
+if (process.env.NODE_ENV === "production") {
+	it("B should not be used", () => {
+		expect(exportsInfoForB).toBe(false);
+	});
+}
 
 it("A should be used", () => {
 	expect(exportsInfoForA).toBe(true);
@@ -27,7 +29,9 @@ it("Z used, inner graph can not determine const usage", () => {
 });
 
 it("Pure super expression should be unused, another used", () => {
-	expect(exportsInfoForMixin1).toBe(false);
+	if (process.env.NODE_ENV === "production") {
+		expect(exportsInfoForMixin1).toBe(false);
+	}
 
 	expect(exportsInfoForMixin2).toBe(true);
 	expect(exportsInfoForMixin3).toBe(true);

test/cases/inner-graph/extend-class2/index.js

@@ -25,20 +25,24 @@ it("A should be used", () => {
 	expect(exprA).toBe(true);
 });
 
-it("B should not be used", () => {
-	expect(declB).toBe(false);
-	expect(exprB).toBe(false);
-});
+if (process.env.NODE_ENV === "production") {
+	it("B should not be used", () => {
+		expect(declB).toBe(false);
+		expect(exprB).toBe(false);
+	});
+}
 
 it("C should be used", () => {
 	expect(declC).toBe(true);
 	expect(exprC).toBe(true);
 });
 
-it("D should not be used", () => {
-	expect(declD).toBe(false);
-	expect(exprD).toBe(false);
-});
+if (process.env.NODE_ENV === "production") {
+	it("D should not be used", () => {
+		expect(declD).toBe(false);
+		expect(exprD).toBe(false);
+	});
+}
 
 it("E should be used", () => {
 	expect(declE).toBe(true);

test/cases/inner-graph/reexport-namespace-and-default/index.js

@@ -1,15 +1,17 @@
-import {exportDefaultUsed as export1} from "./package1/script";
-import {exportDefaultUsed as export2} from "./package1/script2";
-import {exportDefaultUsed as export3} from "./package2/script";
+import { exportDefaultUsed as export1 } from "./package1/script";
+import { exportDefaultUsed as export2 } from "./package1/script2";
+import { exportDefaultUsed as export3 } from "./package2/script";
 
 it("should load module correctly", () => {
-	require('./module');
+	require("./module");
 });
 
-it("default export should be unused", () => {
-	expect(export1).toBe(false);
-	expect(export2).toBe(false);
-});
+if (process.env.NODE_ENV === "production") {
+	it("default export should be unused", () => {
+		expect(export1).toBe(false);
+		expect(export2).toBe(false);
+	});
+}
 
 it("default export should be used", () => {
 	expect(export3).toBe(true);

test/cases/inner-graph/simple/index.js

@@ -12,11 +12,13 @@ it("export should be unused when only unused functions use it", () => {
 	f1();
 	expect(pureUsed).toBe(42);
 	expect(fWithDefault()).toBe(42);
-	expect(exportUsed).toBe(false);
-	expect(export2Used).toBe(true);
-	expect(export3Used).toBe(true);
-	expect(export4Used).toBe(true);
-	expect(export5Used).toBe(true);
-	expect(export6Used).toBe(true);
+	if (process.env.NODE_ENV === "production") {
+		expect(exportUsed).toBe(false);
+		expect(export2Used).toBe(true);
+		expect(export3Used).toBe(true);
+		expect(export4Used).toBe(true);
+		expect(export5Used).toBe(true);
+		expect(export6Used).toBe(true);
+	}
 	return import("./chunk");
 });

test/cases/parsing/harmony-deep-exports/index.js

@@ -32,21 +32,34 @@ it("should be able to call a deep function in commonjs", () => {
 it("should report consistent exports info", () => {
 	const x1 = counter.exportsInfo;
 
-	expect(x1.incrementInfo).toBe(true);
-	expect(x1.counterInfo).toBe(true);
-	expect(x1.resetInfo).toBe(true);
-	expect(x1.unusedExport).toBe(false);
-	expect(x1.unusedExportInfo).toBe(false);
-	expect(x1.somethingElse).toBe(false);
-	expect(x1.somethingElseInfo).toBe(false);
+	if (process.env.NODE_ENV === "production") {
+		expect(x1.incrementInfo).toBe(true);
+		expect(x1.counterInfo).toBe(true);
+		expect(x1.resetInfo).toBe(true);
+		expect(x1.unusedExport).toBe(false);
+		expect(x1.unusedExportInfo).toBe(false);
+		expect(x1.somethingElse).toBe(false);
+		expect(x1.somethingElseInfo).toBe(false);
+		expect(C.exportsInfo.nsInfo).toBe(true);
+		expect(C.exportsInfo.ns2).toBe(false);
+		expect(C.exportsInfo.ns2Info).toBe(false);
+	} else if (process.env.NODE_ENV === "development") {
+		expect(x1.incrementInfo).toBe(undefined);
+		expect(x1.counterInfo).toBe(undefined);
+		expect(x1.resetInfo).toBe(undefined);
+		expect(x1.unusedExport).toBe(true);
+		expect(x1.unusedExportInfo).toBe(undefined);
+		expect(x1.somethingElse).toBe(true);
+		expect(x1.somethingElseInfo).toBe(undefined);
+		expect(C.exportsInfo.nsInfo).toBe(undefined);
+		expect(C.exportsInfo.ns2).toBe(true);
+		expect(C.exportsInfo.ns2Info).toBe(undefined);
+	}
 	expect(x1.increment).toBe(true);
 	expect(x1.counter).toBe(true);
 	expect(x1.reset).toBe(true);
 	expect(x1.incrementProvideInfo).toBe(true);
 	expect(x1.somethingElseProvideInfo).toBe(false);
-	expect(C.exportsInfo.nsInfo).toBe(true);
-	expect(C.exportsInfo.ns2).toBe(false);
-	expect(C.exportsInfo.ns2Info).toBe(false);
 	expect(C.exportsInfo.increment).toBe(x1.increment);
 	expect(C.exportsInfo.counter).toBe(x1.counter);
 	expect(C.exportsInfo.reset).toBe(x1.reset);

test/cases/parsing/harmony-export-import-specifier/index.js

@@ -1,31 +1,37 @@
 "use strict";
 
 import { x, y } from "./a";
-import {d2, usedD1, usedD2} from "./d.js";
-import {b1, usedB1, usedB2, usedB3, usedB4} from "./b.js";
-import {usedE1, usedE2} from "./e.js";
-import {h} from "./h.js";
+import { d2, usedD1, usedD2 } from "./d.js";
+import { b1, usedB1, usedB2, usedB3, usedB4 } from "./b.js";
+import { usedE1, usedE2 } from "./e.js";
+import { h } from "./h.js";
 
-it("namespace export as from commonjs should override named export", function() {
+it("namespace export as from commonjs should override named export", function () {
 	expect(x).toBe(1);
 	expect(y).toBe(3);
 });
 
 it("named namespace export should work correctly", function () {
 	expect(d2).toBe(2);
-	expect(usedD1).toBe(false);
+	if (process.env.NODE_ENV === "production") {
+		expect(usedD1).toBe(false);
+	}
 	expect(usedD2).toBe(true);
 
 	expect(b1.d2).toBe(2);
 	expect(usedB1).toBe(true);
-	expect(usedB2).toBe(false);
-	expect(usedB3).toBe(false);
-	expect(usedB4).toBe(false);
+	if (process.env.NODE_ENV === "production") {
+		expect(usedB2).toBe(false);
+		expect(usedB3).toBe(false);
+		expect(usedB4).toBe(false);
+	}
 });
 
 it("complex case should work correctly", () => {
 	expect(h.f1.e.e1).toBe(10);
 	expect(h.g1.e1).toBe(10);
 	expect(usedE1).toBe(true);
-	expect(usedE2).toBe(false);
+	if (process.env.NODE_ENV === "production") {
+		expect(usedE2).toBe(false);
+	}
 });

test/cases/side-effects/dynamic-reexports/dedupe-target-with-side/a.js

@@ -1,2 +1,2 @@
 export * from "./empty";
-export const valueUsed = __webpack_exports_info__.value.useInfo;
+export const valueUsed = __webpack_exports_info__.value.used;

test/hotCases/unexpected-invalidation/used-exports/index.js

@@ -0,0 +1,13 @@
+import { ghi } from "./subject";
+import value from "./module";
+
+it("should not invalidate subject in unrelated locations", done => {
+	expect(ghi).toBe(42);
+	expect(value).toBe(40);
+	import.meta.webpackHot.accept("./module", () => {
+		expect(ghi).toBe(42);
+		expect(value).toBe(41);
+		done();
+	});
+	NEXT(require("../../update")(done));
+});

test/hotCases/unexpected-invalidation/used-exports/module.js

@@ -0,0 +1,3 @@
+export { abc as default } from "./subject";
+---
+export { def as default } from "./subject";

test/hotCases/unexpected-invalidation/used-exports/subject.js

@@ -0,0 +1,3 @@
+export const abc = 40;
+export const def = 41;
+export const ghi = 42;