Add browser build

This commit uses rollup, same as solana's web3 project uses to bundle a browser-specific build

ts/.gitignore

@@ -0,0 +1 @@
+.rollup.cache/

ts/package.json

@@ -4,6 +4,7 @@
   "description": "Anchor client",
   "module": "./dist/esm/index.js",
   "main": "./dist/cjs/index.js",
+  "browser": "./dist/browser/index.js",
   "license": "(MIT OR Apache-2.0)",
   "types": "dist/cjs/index.d.ts",
   "homepage": "https://github.com/project-serum/anchor#readme",
@@ -21,8 +22,9 @@
     "node": ">=11"
   },
   "scripts": {
-    "build": "rm -rf dist/ && yarn build:node",
+    "build": "rimraf dist/ && yarn build:node && yarn build:browser",
     "build:node": "tsc && tsc -p tsconfig.cjs.json",
+    "build:browser": "rollup --config",
     "lint:fix": "prettier src/** tests/** -w",
     "lint": "prettier src/** tests/** --check",
     "watch": "tsc -p tsconfig.cjs.json --watch",
@@ -49,6 +51,10 @@
   "devDependencies": {
     "@commitlint/cli": "^11.0.0",
     "@commitlint/config-conventional": "^11.0.0",
+    "@rollup/plugin-commonjs": "^21.0.1",
+    "@rollup/plugin-node-resolve": "^13.0.6",
+    "@rollup/plugin-replace": "^3.0.0",
+    "@rollup/plugin-typescript": "^8.3.0",
     "@types/bn.js": "^4.11.6",
     "@types/bs58": "^4.0.1",
     "@types/crypto-hash": "^1.1.2",
@@ -63,9 +69,13 @@
     "jest-config": "27.3.1",
     "lint-staged": "^10.5.0",
     "prettier": "^2.1.2",
+    "rimraf": "^3.0.2",
+    "rollup": "^2.60.2",
+    "rollup-plugin-terser": "^7.0.2",
     "ts-jest": "^27.0.7",
     "ts-jest-resolver": "^2.0.0",
     "ts-node": "^9.0.0",
+    "tslib": "^2.3.1",
     "typedoc": "^0.22.10",
     "typescript": "^4.5.2"
   }

ts/rollup.config.ts

@@ -0,0 +1,54 @@
+import nodeResolve from "@rollup/plugin-node-resolve";
+import typescript from "@rollup/plugin-typescript";
+import replace from "@rollup/plugin-replace";
+import commonjs from "@rollup/plugin-commonjs";
+import { terser } from "rollup-plugin-terser";
+
+const env = process.env.NODE_ENV;
+
+export default {
+  input: "src/index.ts",
+  plugins: [
+    commonjs(),
+    nodeResolve({
+      browser: true,
+      extensions: [".js", ".ts"],
+      dedupe: ["bn.js", "buffer"],
+      preferBuiltins: false,
+    }),
+    typescript({
+      tsconfig: "./tsconfig.base.json",
+      moduleResolution: "node",
+      outDir: "types",
+      target: "es2019",
+      outputToFilesystem: false,
+    }),
+    replace({
+      preventAssignment: true,
+      values: {
+        "process.env.NODE_ENV": JSON.stringify(env),
+        "process.env.BROWSER": JSON.stringify(true),
+      },
+    }),
+    terser(),
+  ],
+  external: [
+    "@project-serum/borsh",
+    "@solana/web3.js",
+    "assert",
+    "base64-js",
+    "bn.js",
+    "bs58",
+    "buffer",
+    "camelcase",
+    "eventemitter3",
+    "js-sha256",
+    "pako",
+    "toml",
+  ],
+  output: {
+    file: "dist/browser/index.js",
+    format: "cjs",
+    sourcemap: true,
+  },
+};