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- import { decode } from "@webassemblyjs/wasm-parser";
- import { traverse } from "@webassemblyjs/ast";
- import { cloneNode } from "@webassemblyjs/ast/lib/clone";
- import { shrinkPaddedLEB128 } from "@webassemblyjs/wasm-opt";
- import { getSectionForNode } from "@webassemblyjs/helper-wasm-bytecode";
- import constants from "@webassemblyjs/helper-wasm-bytecode";
- import { applyOperations } from "./apply";
-
- function hashNode(node) {
- return JSON.stringify(node);
- }
-
- function preprocess(ab) {
- var optBin = shrinkPaddedLEB128(new Uint8Array(ab));
- return optBin.buffer;
- }
-
- function sortBySectionOrder(nodes) {
- nodes.sort(function (a, b) {
- var sectionA = getSectionForNode(a);
- var sectionB = getSectionForNode(b);
- var aId = constants.sections[sectionA];
- var bId = constants.sections[sectionB];
-
- if (typeof aId !== "number" || typeof bId !== "number") {
- throw new Error("Section id not found");
- } // $FlowIgnore ensured above
-
-
- return aId > bId;
- });
- }
-
- export function edit(ab, visitors) {
- ab = preprocess(ab);
- var ast = decode(ab);
- return editWithAST(ast, ab, visitors);
- }
- export function editWithAST(ast, ab, visitors) {
- var operations = [];
- var uint8Buffer = new Uint8Array(ab);
- var nodeBefore;
-
- function before(type, path) {
- nodeBefore = cloneNode(path.node);
- }
-
- function after(type, path) {
- if (path.node._deleted === true) {
- operations.push({
- kind: "delete",
- node: path.node
- }); // $FlowIgnore
- } else if (hashNode(nodeBefore) !== hashNode(path.node)) {
- operations.push({
- kind: "update",
- oldNode: nodeBefore,
- node: path.node
- });
- }
- }
-
- traverse(ast, visitors, before, after);
- uint8Buffer = applyOperations(ast, uint8Buffer, operations);
- return uint8Buffer.buffer;
- }
- export function add(ab, newNodes) {
- ab = preprocess(ab);
- var ast = decode(ab);
- return addWithAST(ast, ab, newNodes);
- }
- export function addWithAST(ast, ab, newNodes) {
- // Sort nodes by insertion order
- sortBySectionOrder(newNodes);
- var uint8Buffer = new Uint8Array(ab); // Map node into operations
-
- var operations = newNodes.map(function (n) {
- return {
- kind: "add",
- node: n
- };
- });
- uint8Buffer = applyOperations(ast, uint8Buffer, operations);
- return uint8Buffer.buffer;
- }
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