Merge pull request #6160 from webpack/wasm/imports

add support for imports in wasm modules

examples/wasm-simple/test.filter.js

@@ -0,0 +1,5 @@
+var supportsWebAssembly = require("../../test/helpers/supportsWebAssembly");
+
+module.exports = function(config) {
+	return supportsWebAssembly();
+};

lib/WebAssemblyModulesPlugin.js

@@ -5,12 +5,15 @@
 "use strict";
 
 const WebAssemblyParser = require("./WebAssemblyParser");
+const WebAssemblyImportDependency = require("./dependencies/WebAssemblyImportDependency");
 
 class WebAssemblyModulesPlugin {
 	apply(compiler) {
 		compiler.hooks.compilation.tap("WebAssemblyModulesPlugin", (compilation, {
 			normalModuleFactory
 		}) => {
+			compilation.dependencyFactories.set(WebAssemblyImportDependency, normalModuleFactory);
+
 			normalModuleFactory.hooks.createParser.for("webassembly/experimental").tap("WebAssemblyModulesPlugin", () => {
 				return new WebAssemblyParser();
 			});

lib/WebAssemblyParser.js

@@ -8,6 +8,7 @@
 // Syntax: https://developer.mozilla.org/en/SpiderMonkey/Parser_API
 
 const Tapable = require("tapable").Tapable;
+const WebAssemblyImportDependency = require("./dependencies/WebAssemblyImportDependency");
 
 class WebAssemblyParser extends Tapable {
 	constructor(options) {
@@ -29,10 +30,13 @@ class WebAssemblyParser extends Tapable {
 		if(typeof WebAssembly !== "undefined") {
 			WebAssembly.compile(source).then(module => {
 				state.module.buildMeta.providedExports = WebAssembly.Module.exports(module).map(exp => exp.name);
+				for(const imp of WebAssembly.Module.imports(module)) {
+					const dep = new WebAssemblyImportDependency(imp.module, imp.name, imp.kind);
+					state.module.addDependency(dep);
+				}
 			}).then(() => callback(null, state), err => callback(err));
 		} else {
-			state.module.buildMeta.providedExports = false;
-			callback(null, state);
+			throw new Error("Can't compile WebAssembly modules without WebAssembly support in current node.js version (Update to latest node.js version)");
 		}
 	}
 }

lib/dependencies/WebAssemblyImportDependency.js

@@ -0,0 +1,27 @@
+/*
+	MIT License http://www.opensource.org/licenses/mit-license.php
+	Author Tobias Koppers @sokra
+*/
+"use strict";
+const ModuleDependency = require("./ModuleDependency");
+
+class WebAssemblyImportDependency extends ModuleDependency {
+	constructor(request, name) {
+		super(request);
+		this.name = name;
+	}
+
+	getReference() {
+		if(!this.module) return null;
+		return {
+			module: this.module,
+			importedNames: [this.name]
+		};
+	}
+
+	get type() {
+		return "wasm import";
+	}
+}
+
+module.exports = WebAssemblyImportDependency;

lib/wasm/WasmModuleTemplatePlugin.js

@@ -5,6 +5,7 @@
 "use strict";
 
 const RawSource = require("webpack-sources").RawSource;
+const WebAssemblyImportDependency = require("../dependencies/WebAssemblyImportDependency");
 
 class WasmModuleTemplatePlugin {
 	apply(moduleTemplate) {
@@ -30,11 +31,40 @@ class WasmModuleTemplatePlugin {
 						return `${module.moduleArgument}.exports = instance.exports;`;
 					}
 				};
+				const generateImports = () => {
+					const depsByRequest = new Map();
+					for(const dep of module.dependencies) {
+						if(dep instanceof WebAssemblyImportDependency) {
+							const request = dep.request;
+							let array = depsByRequest.get(request);
+							if(!array) {
+								depsByRequest.set(request, array = []);
+							}
+							const exportName = dep.name;
+							const usedName = dep.module && dep.module.isUsed(exportName);
+							array.push({
+								exportName,
+								usedName,
+								module: dep.module
+							});
+						}
+					}
+					const importsCode = [];
+					for(const pair of depsByRequest) {
+						const properties = [];
+						for(const data of pair[1]) {
+							properties.push(`\n\t\t${JSON.stringify(data.exportName)}: __webpack_require__(${JSON.stringify(data.module.id)})[${JSON.stringify(data.usedName)}]`);
+						}
+						importsCode.push(`\n\t${JSON.stringify(pair[0])}: {${properties.join(",")}\n\t}`);
+					}
+					return importsCode.join(",");
+				};
 				const source = new RawSource([
 					"\"use strict\";",
 					"",
 					"// Instanciate WebAssembly module",
-					"var instance = new WebAssembly.Instance(__webpack_require__.w[module.i], {});",
+					"var instance = new WebAssembly.Instance(__webpack_require__.w[module.i], {" + generateImports(),
+					"});",
 					"",
 					"// export exports from WebAssmbly module",
 					// TODO rewrite this to getters depending on exports to support circular dependencies

test/Examples.test.js

@@ -11,6 +11,11 @@ describe("Examples", () => {
 	const examples = require("../examples/examples.js");
 
 	examples.forEach((examplePath) => {
+		const filterPath = path.join(examplePath, "test.filter.js");
+		if(fs.existsSync(filterPath) && !require(filterPath)()) {
+			describe.skip(path.relative(basePath, examplePath), () => it("filtered"));
+			return;
+		}
 		it("should compile " + path.relative(basePath, examplePath), function(done) {
 			this.timeout(20000);
 			let options = {};

test/cases/wasm/import-wasm-wasm/index.js

@@ -0,0 +1,6 @@
+it("should allow to run a WebAssembly module with imports", function() {
+	return import("./wasm.wasm").then(function(wasm) {
+		const result = wasm.addNumber(20);
+		result.should.be.eql(42);
+	});
+});

test/cases/wasm/import-wasm-wasm/test.filter.js

@@ -0,0 +1,5 @@
+var supportsWebAssembly = require("../../../helpers/supportsWebAssembly");
+
+module.exports = function(config) {
+	return supportsWebAssembly();
+};

test/cases/wasm/imports-circular/index.js

@@ -0,0 +1,5 @@
+it("should allow to run a WebAssembly module importing JS circular", function() {
+	return import("./module").then(function(mod) {
+		mod.result.should.be.eql(42);
+	});
+});

test/cases/wasm/imports-circular/module.js

@@ -0,0 +1,7 @@
+import { addNumber } from "./wasm.wasm";
+
+export var result = addNumber(22);
+
+export function getNumber() {
+	return 20;
+}

test/cases/wasm/imports-circular/test.filter.js

@@ -0,0 +1,5 @@
+var supportsWebAssembly = require("../../../helpers/supportsWebAssembly");
+
+module.exports = function(config) {
+	return supportsWebAssembly();
+};

test/cases/wasm/imports/index.js

@@ -0,0 +1,6 @@
+it("should allow to run a WebAssembly module with imports", function() {
+	return import("./wasm.wasm?1").then(function(wasm) {
+		const result = wasm.addNumber(3);
+		result.should.be.eql(11);
+	});
+});

test/cases/wasm/imports/module.js

@@ -0,0 +1,3 @@
+export function getNumber() {
+	return 8;
+}

test/cases/wasm/imports/test.filter.js

@@ -0,0 +1,5 @@
+var supportsWebAssembly = require("../../../helpers/supportsWebAssembly");
+
+module.exports = function(config) {
+	return supportsWebAssembly();
+};