Mocha&Chai update (#1499)

- upgrade Mocha and Chai version
- dump exception error object properties (works well with Chakra)
- use Babel to translate ES module to umd
- replace bigint notation (with `n` suffix) unsupported by Chakra
- script loading tweaks for unittests to support `globalThis` and Chai
exports

Author: CedricGuillemet

Apps/UnitTests/CMakeLists.txt

@@ -9,8 +9,8 @@ set(SCRIPTS
 set(EXTERNAL_SCRIPTS
     "../node_modules/babylonjs/babylon.max.js"
     "../node_modules/babylonjs-materials/babylonjs.materials.js"
-    "../node_modules/chai/chai.js"
-    "../node_modules/mocha/mocha.js")
+    "../node_modules/chai/chai.umd.js"
+    "../node_modules/mocha/mocha.umd.js")
 
 set(SOURCES
     "Shared/Shared.h"

Apps/UnitTests/Shared/Shared.cpp

@@ -89,8 +89,31 @@ TEST(JavaScript, All)
     loader.Eval("location = { href: '' };", ""); // Required for Mocha.js as we do not have a location in Babylon Native
     loader.LoadScript("app:///Scripts/babylon.max.js");
     loader.LoadScript("app:///Scripts/babylonjs.materials.js");
-    loader.LoadScript("app:///Scripts/chai.js");
-    loader.LoadScript("app:///Scripts/mocha.js");
+    loader.Eval("exports = {};", "");             // Required for Chai.js as we do not have exports in Babylon Native
+    // Required for Mocha.js as self and globalThis don't exist
+    // This should be removed once using Webpack and making a bundle with test.ts instead of a .js
+    loader.Eval(R"(
+            (function() {
+                if (typeof globalThis === 'object') return;
+
+                Object.defineProperty(Object.prototype, '__magic__', {
+                  get: function() {
+                    return this;
+                  },
+                  configurable : true
+                    });
+
+                __magic__.globalThis = __magic__;
+                delete Object.prototype.__magic__;
+            })();
+
+            if (typeof self === 'undefined') {
+                self = globalThis;
+            }
+        )", "");
+    loader.LoadScript("app:///Scripts/chai.umd.js");
+    loader.Eval("globalThis.chai = exports;", "");
+    loader.LoadScript("app:///Scripts/mocha.umd.js");
     loader.LoadScript("app:///Scripts/tests.js");
 
     device.StartRenderingCurrentFrame();

Apps/babel-plugin-replace-bigint.js

@@ -0,0 +1,13 @@
+module.exports = function() {
+  return {
+    visitor: {
+      BigIntLiteral(path) {
+        const value = path.node.value;  // Get the BigInt literal value
+        path.replaceWith({
+          type: 'NumericLiteral',
+          value: Number(value),  // Convert BigInt to Number
+        });
+      },
+    },
+  };
+};

Apps/babel.config.json

@@ -0,0 +1,10 @@
+{
+  "presets": [
+    ["@babel/preset-env", {
+      "targets": {
+        "ie": "11"
+      }
+    }]
+  ],
+  "plugins": ["./babel-plugin-replace-bigint"]
+}