@webassemblyjs/wasm-edit

> Rewrite a WASM binary

Replace in-place an AST node in the binary.

Installation

``sh
yarn add @webassemblyjs/wasm-edit
`

Usage

Update:

`js
import { edit } from "@webassemblyjs/wasm-edit";

const binary = [/.../];

const visitors = {
ModuleImport({ node }) {
node.module = "foo";
node.name = "bar";
}
};

const newBinary = edit(binary, visitors);
`

Replace:

`js
import { edit } from "@webassemblyjs/wasm-edit";

const binary = [/.../];

const visitors = {
Instr(path) {
const newNode = t.callInstruction(t.indexLiteral(0));
path.replaceWith(newNode);
}
};

const newBinary = edit(binary, visitors);
`

Remove:

`js
import { edit } from "@webassemblyjs/wasm-edit";

const binary = [/.../];

const visitors = {
ModuleExport({ node }) {
path.remove()
}
};

const newBinary = edit(binary, visitors);
`

Insert:

`js
import { add } from "@webassemblyjs/wasm-edit";

const binary = [/.../];

const newBinary = add(actualBinary, [
t.moduleImport("env", "mem", t.memory(t.limit(1)))
]);
`

Providing the AST

Providing an AST allows you to handle the decoding yourself, here is the API:

`js
addWithAST(Program, ArrayBuffer, Array): ArrayBuffer;
editWithAST(Program, ArrayBuffer, visitors): ArrayBuffer;
``

Note that the AST will be updated in-place.