webpack/lib/WebAssemblyParser.js

75 lines
1.7 KiB
JavaScript

/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
const { traverse } = require("@webassemblyjs/ast");
const { decode } = require("@webassemblyjs/wasm-parser");
const { Tapable } = require("tapable");
const WebAssemblyImportDependency = require("./dependencies/WebAssemblyImportDependency");
const isMemoryImport = moduleImport => moduleImport.descr.type === "Memory";
const isTableImport = moduleImport => moduleImport.descr.type === "Table";
const decoderOpts = {
ignoreCodeSection: true,
ignoreDataSection: true
};
function nonSupportImportOfType(type) {
const e = new Error("Unsupported import of type " + JSON.stringify(type));
e.stack = "";
return e;
}
class WebAssemblyParser extends Tapable {
constructor(options) {
super();
this.hooks = {};
this.options = options;
}
parse(binary, state) {
// flag it as ESM
state.module.buildMeta.exportsType = "namespace";
// parse it
const ast = decode(binary, decoderOpts);
// extract imports and exports
const exports = (state.module.buildMeta.providedExports = []);
traverse(ast, {
ModuleExport({ node }) {
exports.push(node.name);
},
ModuleImport({ node }) {
// Prevent importing a Memory or Table for now
// Depends on https://github.com/WebAssembly/esm-integration
if (isMemoryImport(node) === true) {
throw nonSupportImportOfType("Memory");
}
if (isTableImport(node) === true) {
throw nonSupportImportOfType("Table");
}
const dep = new WebAssemblyImportDependency(
node.module,
node.name,
node.descr
);
state.module.addDependency(dep);
}
});
return state;
}
}
module.exports = WebAssemblyParser;