DEV: Upgrade babel & remove vendored safari-bugfix transformation (#28208)

The Safari 15 bugfix has been rolled into @babel/preset-env in the most recent version, so we no longer need to carry our vendored copy.

This commit updates @babel/preset-env, runs npx yarn-deduplicate yarn.lock, and removes the vendored transform.

This commit also refactors our theme transpiler to use @babel/preset-env, with the same list of target browsers as our ember-cli build uses. This means we no longer need to maintain a separate list of babel transforms for themes.

app/assets/javascripts/admin/package.json

@@ -14,7 +14,7 @@
     "start": "ember serve"
   },
   "dependencies": {
-    "@babel/core": "^7.24.9",
+    "@babel/core": "^7.25.2",
     "discourse-common": "1.0.0",
     "ember-cli-babel": "^8.2.0",
     "ember-cli-htmlbars": "^6.3.0",

app/assets/javascripts/discourse-common/package.json

@@ -14,7 +14,7 @@
     "start": "ember serve"
   },
   "dependencies": {
-    "@babel/core": "^7.24.9",
+    "@babel/core": "^7.25.2",
     "@uppy/aws-s3": "3.0.6",
     "@uppy/aws-s3-multipart": "3.1.3",
     "@uppy/core": "3.0.4",

app/assets/javascripts/discourse-plugins/package.json

@@ -8,7 +8,7 @@
     "ember-addon"
   ],
   "dependencies": {
-    "@babel/core": "^7.24.9",
+    "@babel/core": "^7.25.2",
     "deprecation-silencer": "1.0.0",
     "discourse-widget-hbs": "1.0.0",
     "ember-cli-babel": "^8.2.0",

app/assets/javascripts/discourse-widget-hbs/package.json

@@ -14,7 +14,7 @@
     "start": "ember serve"
   },
   "dependencies": {
-    "@babel/core": "^7.24.9",
+    "@babel/core": "^7.25.2",
     "ember-auto-import": "^2.7.4",
     "ember-cli-babel": "^8.2.0",
     "ember-cli-htmlbars": "^6.3.0",

app/assets/javascripts/discourse/lib/babel-plugin-safari-class-fields-bugfix.js

@@ -1,97 +0,0 @@
-function wrapInitializer(path, babel) {
-  function needsWrapping(node) {
-    if (t.isLiteral(node) && !t.isTemplateLiteral(node)) {
-      return false;
-    }
-
-    if (
-      t.isCallExpression(node) ||
-      t.isOptionalCallExpression(node) ||
-      t.isNewExpression(node)
-    ) {
-      return needsWrapping(node.callee) || node.arguments.some(needsWrapping);
-    }
-
-    if (t.isTemplateLiteral(node)) {
-      return node.expressions.some(needsWrapping);
-    }
-
-    if (t.isTaggedTemplateExpression(node)) {
-      return needsWrapping(node.tag) || needsWrapping(node.quasi);
-    }
-
-    if (t.isArrayExpression(node)) {
-      return node.elements.some(needsWrapping);
-    }
-
-    if (t.isObjectExpression(node)) {
-      return node.properties.some((prop) => {
-        if (t.isObjectProperty(prop)) {
-          return (
-            needsWrapping(prop.value) ||
-            (prop.computed && needsWrapping(prop.key))
-          );
-        }
-        if (t.isObjectMethod(prop)) {
-          return false;
-        }
-        return false;
-      });
-    }
-
-    if (t.isMemberExpression(node) || t.isOptionalMemberExpression(node)) {
-      return (
-        needsWrapping(node.object) ||
-        (node.computed && needsWrapping(node.property))
-      );
-    }
-
-    if (
-      t.isFunctionExpression(node) ||
-      t.isArrowFunctionExpression(node) ||
-      t.isClassExpression(node)
-    ) {
-      return false;
-    }
-
-    if (t.isThisExpression(node)) {
-      return false;
-    }
-
-    if (t.isSequenceExpression(node)) {
-      return node.expressions.some(needsWrapping);
-    }
-
-    // Is an identifier, or anything else not covered above
-    return true;
-  }
-
-  const { types: t } = babel;
-  const { value } = path.node;
-
-  if (value && needsWrapping(value)) {
-    path.node.value = t.callExpression(
-      t.arrowFunctionExpression([], value),
-      []
-    );
-  }
-}
-
-function makeVisitor(babel) {
-  return {
-    ClassProperty(path) {
-      wrapInitializer(path, babel);
-    },
-    ClassPrivateProperty(path) {
-      wrapInitializer(path, babel);
-    },
-  };
-}
-
-module.exports = function wrapClassFields(babel) {
-  return {
-    post(file) {
-      babel.traverse(file.ast, makeVisitor(babel), file.scope, this);
-    },
-  };
-};

app/assets/javascripts/discourse/lib/common-babel-config.js

@@ -15,7 +15,6 @@ module.exports = function generateCommonBabelConfig() {
             runEarly: true,
           },
         ],
-        require.resolve("./babel-plugin-safari-class-fields-bugfix"),
       ],
     },
   };

app/assets/javascripts/discourse/package.json

@@ -37,8 +37,8 @@
     "pretty-text": "1.0.0"
   },
   "devDependencies": {
-    "@babel/core": "^7.24.9",
+    "@babel/core": "^7.25.2",
-    "@babel/standalone": "^7.24.10",
+    "@babel/standalone": "^7.25.3",
     "@colors/colors": "^1.6.0",
     "@discourse/backburner.js": "^2.7.1-0",
     "@discourse/itsatrap": "^2.0.10",

app/assets/javascripts/float-kit/package.json

@@ -14,7 +14,7 @@
     "start": "ember serve"
   },
   "dependencies": {
-    "@babel/core": "^7.24.9",
+    "@babel/core": "^7.25.2",
     "ember-auto-import": "^2.7.4",
     "ember-cli-babel": "^8.2.0",
     "ember-cli-htmlbars": "^6.3.0",

app/assets/javascripts/pretty-text/package.json

@@ -14,7 +14,7 @@
     "start": "ember serve"
   },
   "dependencies": {
-    "@babel/core": "^7.24.9",
+    "@babel/core": "^7.25.2",
     "discourse-common": "1.0.0",
     "ember-auto-import": "^2.7.4",
     "ember-cli-babel": "^8.2.0",

app/assets/javascripts/select-kit/package.json

@@ -14,7 +14,7 @@
     "start": "ember serve"
   },
   "dependencies": {
-    "@babel/core": "^7.24.9",
+    "@babel/core": "^7.25.2",
     "ember-auto-import": "^2.7.4",
     "ember-cli-babel": "^8.2.0",
     "ember-cli-htmlbars": "^6.3.0",

app/assets/javascripts/theme-transpiler/build.js

@@ -52,7 +52,7 @@ esbuild
       util: "./node_modules/@zxing/text-encoding",
     },
     define: {
-      process: `{ "env": {} }`,
+      process: `{ "env": { "EMBER_ENV": "production" } }`,
     },
     external: ["fs", "path"],
     entryPoints: ["./app/assets/javascripts/theme-transpiler/transpiler.js"],

app/assets/javascripts/theme-transpiler/package.json

@@ -7,7 +7,7 @@
   "license": "GPL-2.0-only",
   "keywords": [],
   "dependencies": {
-    "@babel/standalone": "^7.24.10",
+    "@babel/standalone": "^7.25.3",
     "@zxing/text-encoding": "^0.9.0",
     "babel-plugin-ember-template-compilation": "^2.2.5",
     "content-tag": "^2.0.1",

app/assets/javascripts/theme-transpiler/transpiler.js

@@ -30,8 +30,8 @@ import getRandomValues from "polyfill-crypto.getrandomvalues";
 import { minify as terserMinify } from "terser";
 import RawHandlebars from "discourse-common/addon/lib/raw-handlebars";
 import { WidgetHbsCompiler } from "discourse-widget-hbs/lib/widget-hbs-compiler";
-import BabelPluginSafariClassFieldsBugfix from "../discourse/lib/babel-plugin-safari-class-fields-bugfix";
 globalThis.crypto = { getRandomValues };
+import { browsers } from "../discourse/config/targets";
 
 const thisFallbackPlugin = EmberThisFallback._buildPlugin({
   enableLogging: false,
@@ -127,8 +127,7 @@ globalThis.compileRawTemplate = function (source, themeId) {
 };
 
 globalThis.transpile = function (source, options = {}) {
-  const { moduleId, filename, extension, skipModule, themeId, commonPlugins } =
+  const { moduleId, filename, extension, skipModule, themeId } = options;
-    options;
 
   if (extension === "gjs") {
     const preprocessor = new Preprocessor();
@@ -140,10 +139,7 @@ globalThis.transpile = function (source, options = {}) {
   if (moduleId && !skipModule) {
     plugins.push(["transform-modules-amd", { noInterop: true }]);
   }
-  commonPlugins.find((p) => p[0] === "decorator-transforms")[0] =
+  plugins.push([DecoratorTransforms, { runEarly: true }]);
-    DecoratorTransforms;
-  plugins.push(...commonPlugins);
-  plugins.unshift(BabelPluginSafariClassFieldsBugfix);
 
   try {
     return babelTransform(source, {
@@ -151,6 +147,17 @@ globalThis.transpile = function (source, options = {}) {
       filename,
       ast: false,
       plugins,
+      presets: [
+        [
+          "env",
+          {
+            modules: false,
+            targets: {
+              browsers,
+            },
+          },
+        ],
+      ],
     }).code;
   } catch (error) {
     // Workaround for https://github.com/rubyjs/mini_racer/issues/262

lib/discourse_js_processor.rb

@@ -6,15 +6,6 @@ class DiscourseJsProcessor
   class TranspileError < StandardError
   end
 
-  # To generate a list of babel plugins used by ember-cli, set
-  # babel: { debug: true } in ember-cli-build.js, then run `yarn ember build -prod`
-  DISCOURSE_COMMON_BABEL_PLUGINS = [
-    ["decorator-transforms", { runEarly: true }],
-    "proposal-class-static-block",
-    "transform-parameters",
-    "proposal-export-namespace-from",
-  ]
-
   def self.ember_cli?(filename)
     filename.include?("/app/assets/javascripts/discourse/dist/")
   end
@@ -161,7 +152,6 @@ class DiscourseJsProcessor
           filename: logical_path || "unknown",
           extension: extension,
           themeId: theme_id,
-          commonPlugins: DISCOURSE_COMMON_BABEL_PLUGINS,
         },
       )
     end