From ff09f82f819fc6185fbc5a842267fc9cffadd711 Mon Sep 17 00:00:00 2001
From: Bruno Windels <brunow@matrix.org>
Date: Wed, 16 Sep 2020 16:58:35 +0200
Subject: [PATCH] add bs58 as a dependency

override some of its imports as they would just add
a lot of nodejs fluff that needs stubbing out for a browser.
---
 package.json                                  |  1 +
 scripts/package-overrides/buffer/index.js     |  6 +++++
 .../package-overrides/safe-buffer/index.js    |  1 +
 scripts/post-install.mjs                      | 26 +++++++++++++++++--
 yarn.lock                                     | 19 ++++++++++++++
 5 files changed, 51 insertions(+), 2 deletions(-)
 create mode 100644 scripts/package-overrides/buffer/index.js
 create mode 100644 scripts/package-overrides/safe-buffer/index.js

diff --git a/package.json b/package.json
index 9e22569a..7faaea2c 100644
--- a/package.json
+++ b/package.json
@@ -48,6 +48,7 @@
   },
   "dependencies": {
     "another-json": "^0.2.0",
+    "bs58": "^4.0.1",
     "olm": "https://packages.matrix.org/npm/olm/olm-3.1.4.tgz"
   }
 }
diff --git a/scripts/package-overrides/buffer/index.js b/scripts/package-overrides/buffer/index.js
new file mode 100644
index 00000000..951b344b
--- /dev/null
+++ b/scripts/package-overrides/buffer/index.js
@@ -0,0 +1,6 @@
+module.exports = class Buffer {
+    static isBuffer() {return false;}
+    static from(arrayBuffer) {return arrayBuffer;}
+    static allocUnsafe(size) {return Buffer.alloc(size);}
+    static alloc(size) {return new Uint8Array(size);}
+};
diff --git a/scripts/package-overrides/safe-buffer/index.js b/scripts/package-overrides/safe-buffer/index.js
new file mode 100644
index 00000000..93a10446
--- /dev/null
+++ b/scripts/package-overrides/safe-buffer/index.js
@@ -0,0 +1 @@
+module.exports.Buffer = require("buffer");
diff --git a/scripts/post-install.mjs b/scripts/post-install.mjs
index 328f8c7c..16332c5d 100644
--- a/scripts/post-install.mjs
+++ b/scripts/post-install.mjs
@@ -22,18 +22,34 @@ import { fileURLToPath } from 'url';
 import { dirname } from 'path';
 // needed to translate commonjs modules to esm
 import commonjs from '@rollup/plugin-commonjs';
-// multi-entry plugin so we can add polyfill file to main
+import { nodeResolve } from '@rollup/plugin-node-resolve';
 import {removeDirIfExists} from "./common.mjs";
 
 const __filename = fileURLToPath(import.meta.url);
 const __dirname = dirname(__filename);
 const projectDir = path.join(__dirname, "../");
 
+/** function used to resolve common-js require calls below. */
+function packageIterator(request, start, defaultIterator) {
+    // this is just working for bs58, would need to tune it further for other dependencies
+    if (request === "safe-buffer") {
+        return [path.join(projectDir, "/scripts/package-overrides/safe-buffer")];
+    } else if (request === "buffer/") {
+        return [path.join(projectDir, "/scripts/package-overrides/buffer")];
+    } else {
+        return defaultIterator();
+    }
+}
+
 async function commonjsToESM(src, dst) {
     // create js bundle
     const bundle = await rollup({
         input: src,
-        plugins: [commonjs()]
+        plugins: [commonjs(), nodeResolve({
+            browser: true,
+            preferBuiltins: false,
+            customResolveOptions: {packageIterator}
+        })]
     });
     const {output} = await bundle.generate({
         format: 'es'
@@ -59,6 +75,12 @@ async function populateLib() {
         path.join(modulesDir, 'another-json/another-json.js'),
         path.join(libDir, "another-json/index.js")
     );
+    // transpile bs58 to esm
+    await fs.mkdir(path.join(libDir, "bs58/"));
+    await commonjsToESM(
+        path.join(modulesDir, 'bs58/index.js'),
+        path.join(libDir, "bs58/index.js")
+    );
 }
 
 populateLib();
diff --git a/yarn.lock b/yarn.lock
index d1bf27a2..89891ce7 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -931,6 +931,13 @@ balanced-match@^1.0.0:
   resolved "https://registry.yarnpkg.com/balanced-match/-/balanced-match-1.0.0.tgz#89b4d199ab2bee49de164ea02b89ce462d71b767"
   integrity sha1-ibTRmasr7kneFk6gK4nORi1xt2c=
 
+base-x@^3.0.2:
+  version "3.0.8"
+  resolved "https://registry.yarnpkg.com/base-x/-/base-x-3.0.8.tgz#1e1106c2537f0162e8b52474a557ebb09000018d"
+  integrity sha512-Rl/1AWP4J/zRrk54hhlxH4drNxPJXYUaKffODVI53/dAsV4t9fBxyxYKAVPU1XBHxYwOWP9h9H0hM2MVw4YfJA==
+  dependencies:
+    safe-buffer "^5.0.1"
+
 boolbase@~1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/boolbase/-/boolbase-1.0.0.tgz#68dff5fbe60c51eb37725ea9e3ed310dcc1e776e"
@@ -954,6 +961,13 @@ browserslist@^4.12.0, browserslist@^4.8.5:
     escalade "^3.0.2"
     node-releases "^1.1.60"
 
+bs58@^4.0.1:
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/bs58/-/bs58-4.0.1.tgz#be161e76c354f6f788ae4071f63f34e8c4f0a42a"
+  integrity sha1-vhYedsNU9veIrkBx9j806MTwpCo=
+  dependencies:
+    base-x "^3.0.2"
+
 builtin-modules@^3.1.0:
   version "3.1.0"
   resolved "https://registry.yarnpkg.com/builtin-modules/-/builtin-modules-3.1.0.tgz#aad97c15131eb76b65b50ef208e7584cd76a7484"
@@ -1726,6 +1740,11 @@ rollup@^2.26.4:
   optionalDependencies:
     fsevents "~2.1.2"
 
+safe-buffer@^5.0.1:
+  version "5.2.1"
+  resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.2.1.tgz#1eaf9fa9bdb1fdd4ec75f58f9cdb4e6b7827eec6"
+  integrity sha512-rp3So07KcdmmKbGvgaNxQSJr7bGVSVk5S9Eq1F+ppbRo70+YeaDxkw5Dd8NPN+GD6bjnYm2VuPuCXmpuYvmCXQ==
+
 safe-buffer@~5.1.1:
   version "5.1.2"
   resolved "https://registry.yarnpkg.com/safe-buffer/-/safe-buffer-5.1.2.tgz#991ec69d296e0313747d59bdfd2b745c35f8828d"