From 6497d6d67660fc383410f81262d7e3432e44bd2e Mon Sep 17 00:00:00 2001
From: Ivan Enderlin <ivan@mnt.io>
Date: Wed, 2 Nov 2022 16:19:17 +0100
Subject: [PATCH] feat(crypto-js): Make `scripts/build.sh` compatible with
 macOS.
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This patch also improves the “phrasing”, simplifies the code a little bit etc.
Small stuff.
---
 .../matrix-sdk-crypto-js/scripts/build.sh     | 30 +++++++++----------
 .../{ => scripts}/unbase64.js                 |  8 ++---
 2 files changed, 18 insertions(+), 20 deletions(-)
 rename bindings/matrix-sdk-crypto-js/{ => scripts}/unbase64.js (89%)

diff --git a/bindings/matrix-sdk-crypto-js/scripts/build.sh b/bindings/matrix-sdk-crypto-js/scripts/build.sh
index 835b0ad8d..3f828b47d 100755
--- a/bindings/matrix-sdk-crypto-js/scripts/build.sh
+++ b/bindings/matrix-sdk-crypto-js/scripts/build.sh
@@ -1,35 +1,35 @@
 #!/bin/bash
 #
-# Build the javascript modules
+# Build the JavaScript modules
 #
 # This script is really a workaround for https://github.com/rustwasm/wasm-pack/issues/1074.
 #
-# Currently, the only reliable way to load webassembly in all the JS
+# Currently, the only reliable way to load WebAssembly in all the JS
 # environments we want to target (web-via-webpack, web-via-browserify, jest)
 # seems to be to pack the WASM into base64, and then unpack it and instantiate
 # it at runtime.
 #
 # Hopefully one day, https://github.com/rustwasm/wasm-pack/issues/1074 will be
 # fixed and this will be unnecessary.
+#
+# Run this script from the root of the project, i.e. from the parent directory of this file.
 
 set -e
 
 RUSTFLAGS='-C opt-level=z' WASM_BINDGEN_WEAKREF=1 wasm-pack build --release --target nodejs --scope matrix-org --out-dir ./pkg
 
-# convert the wasm into a js file that exports the b64'ed wasm
-{
-    echo 'module.exports = `'
-    base64 pkg/matrix_sdk_crypto_js_bg.wasm
-    echo '`;'
-} > pkg/matrix_sdk_crypto_js_bg.wasm.js
+# Convert the Wasm into a JS file that exports the base64'ed Wasm.
+echo "module.exports = '$(base64 pkg/matrix_sdk_crypto_js_bg.wasm)';" > pkg/matrix_sdk_crypto_js_bg.wasm.js
 
-# copy in the unbase64 module
-cp unbase64.js pkg/
+# Copy in the unbase64 module
+cp scripts/wasm.js pkg/
 
-# In the javascript:
-#  1. replace the lines that load the wasm
-#  2. remove the imports of TextDecoder and TextEncoder. We rely on the global defaults.
+# In the JavaScript:
+#  1. Replace the lines that load the Wasm,
+#  2. Remove the imports of `TextDecoder` and `TextEncoder`. We rely on the global defaults.
 loadwasm='const bytes = require("./unbase64.js")(require("./matrix_sdk_crypto_js_bg.wasm.js"));'
-sed -i -e "/^const path = /,+1 c$loadwasm" \
-    -e '/= require(`util`)/d' \
+sed -i '' \
+    -e "/^const path = /d" \
+    -e "s@^const bytes =.*@${loadwasm}@" \
+    -e '/Text..coder.*= require(.util.)/d' \
     pkg/matrix_sdk_crypto_js.js
diff --git a/bindings/matrix-sdk-crypto-js/unbase64.js b/bindings/matrix-sdk-crypto-js/scripts/unbase64.js
similarity index 89%
rename from bindings/matrix-sdk-crypto-js/unbase64.js
rename to bindings/matrix-sdk-crypto-js/scripts/unbase64.js
index 445d69097..fa82e2dde 100644
--- a/bindings/matrix-sdk-crypto-js/unbase64.js
+++ b/bindings/matrix-sdk-crypto-js/scripts/unbase64.js
@@ -1,10 +1,10 @@
-// Javascript module which exports a function which will un-base64 a string
+// JavaScript module which exports a function which will un-base64 a string.
 //
 // Based on the code at https://developer.mozilla.org/en-US/docs/Glossary/Base64#solution_2_%E2%80%93_rewriting_atob_and_btoa_using_typedarrays_and_utf-8
 
 const lookup = new Uint8Array([0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 62, 0, 62, 0, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 0, 0, 0, 0, 63, 0, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51]);
 
-function base64DecToArr(sBase64) {
+module.exports = (sBase64) => {
   const sB64Enc = sBase64.replace(/[^A-Za-z0-9+/]/g, "");
   const nInLen = sB64Enc.length;
   const nOutLen = (nInLen * 3 + 1) >> 2;
@@ -29,6 +29,4 @@ function base64DecToArr(sBase64) {
   }
 
   return taBytes;
-}
-
-module.exports = base64DecToArr;
+};