Add a new script to include an example module for Cypress tests

Signed-off-by: Dominik Henneke <[email protected]>

module_system/BuildConfig.ts

@@ -26,8 +26,9 @@ export type BuildConfig = {
 };
 
 export function readBuildConfig(): BuildConfig {
-    if (fs.existsSync("./build_config.yaml")) {
-        return YAML.parse(fs.readFileSync("./build_config.yaml", "utf-8"));
+    const configFile = process.env.ELEMENT_BUILD_CONFIG ?? "./build_config.yaml";
+    if (fs.existsSync(configFile)) {
+        return YAML.parse(fs.readFileSync(configFile, "utf-8"));
     }
     return {}; // no config
 }

package.json

@@ -48,6 +48,7 @@
         "start:https": "concurrently --kill-others-on-fail --prefix \"{time} [{name}]\" -n res,element-js \"yarn start:res\" \"yarn start:js --https\"",
         "start:res": "yarn build:jitsi && node scripts/copy-res.js -w",
         "start:js": "webpack-dev-server --output-filename=bundles/_dev_/[name].js --output-chunk-filename=bundles/_dev_/[name].js -w --mode development --disable-host-check --hot",
+        "start:e2e": "ELEMENT_BUILD_CONFIG='node_modules/matrix-react-sdk/cypress/example_module/build_config.yaml' yarn start",
         "lint": "yarn lint:types && yarn lint:js && yarn lint:style",
         "lint:js": "yarn lint:js:src && yarn lint:js:module_system",
         "lint:js:src": "eslint --max-warnings 0 src test && prettier --check .",

webpack.config.js

@@ -277,6 +277,11 @@ module.exports = (env, argv) => {
                         // probably be removed.
                         if (f.includes("@vector-im/compound-web")) return true;
 
+                        // In Cypress we define an example module to test the Module API.
+                        // This is written in typescript and directly imported, so we need
+                        // to apply babel to it to compile it.
+                        if (f.includes("example_module")) return true;
+
                         // but we can't run all of our dependencies through babel (many of them still
                         // use module.exports which breaks if babel injects an 'include' for its
                         // polyfills: probably fixable but babeling all our dependencies is probably