chore: move babel-plugin-transform-typescript-metadata in plugins

package.json

@@ -26,19 +26,22 @@
   },
   "devDependencies": {
     "@babel/core": "^7.22.15",
+    "@babel/helper-plugin-utils": "^7.22.5",
     "@babel/plugin-proposal-decorators": "^7.22.15",
-    "@babel/plugin-transform-export-namespace-from": "^7.18.9",
-    "@babel/plugin-transform-nullish-coalescing-operator": "^7.18.6",
-    "@babel/plugin-transform-optional-chaining": "^7.21.0",
     "@babel/plugin-syntax-class-properties": "^7.12.13",
     "@babel/plugin-syntax-import-assertions": "^7.22.5",
+    "@babel/plugin-transform-export-namespace-from": "^7.18.9",
     "@babel/plugin-transform-modules-commonjs": "^7.22.15",
+    "@babel/plugin-transform-nullish-coalescing-operator": "^7.18.6",
+    "@babel/plugin-transform-optional-chaining": "^7.21.0",
     "@babel/plugin-transform-typescript": "^7.22.15",
     "@babel/preset-typescript": "^7.22.15",
     "@babel/template": "^7.22.15",
+    "@babel/traverse": "^7.22.15",
     "@babel/types": "^7.22.15",
     "@types/babel__core": "^7.20.1",
     "@types/babel__template": "^7.4.1",
+    "@types/babel__traverse": "^7.20.1",
     "@types/node": "^20.5.9",
     "@types/object-hash": "^3.0.4",
     "@types/resolve": "^1.20.2",
@@ -47,7 +50,6 @@
     "acorn": "^8.10.0",
     "babel-plugin-dynamic-import-node": "^2.3.3",
     "babel-plugin-parameter-decorator": "^1.0.16",
-    "@sirenko/babel-plugin-transform-typescript-metadata": "^0.3.2-fix-reflect",
     "changelogen": "^0.5.5",
     "config": "^3.3.9",
     "create-require": "^1.1.1",

src/babel.ts

@@ -6,6 +6,7 @@ import type {
 import { TransformOptions, TRANSFORM_RESULT } from "./types";
 import { TransformImportMetaPlugin } from "./plugins/babel-plugin-transform-import-meta";
 import { importMetaEnvPlugin } from "./plugins/import-meta-env";
+import babelPluginTransformTypescriptMetadata from "./plugins/babel-plugin-transform-typescript-metadata";
 
 export default function transform(opts: TransformOptions): TRANSFORM_RESULT {
   const _opts: BabelTransformOptions & { plugins: PluginItem[] } = {
@@ -37,7 +38,7 @@ export default function transform(opts: TransformOptions): TRANSFORM_RESULT {
     ]);
     // `unshift` because these plugin must come before `@babel/plugin-syntax-class-properties`
     _opts.plugins.unshift(
-      [require("@sirenko/babel-plugin-transform-typescript-metadata")],
+      [babelPluginTransformTypescriptMetadata],
       [require("@babel/plugin-proposal-decorators"), { legacy: true }],
     );
     _opts.plugins.push(require("babel-plugin-parameter-decorator"));

src/plugins/babel-plugin-transform-typescript-metadata/index.ts

@@ -0,0 +1,47 @@
+import { PluginObj } from '@babel/core';
+import { declare } from '@babel/helper-plugin-utils';
+import { parameterVisitor } from './parameter/parameter-visitor';
+import { metadataVisitor } from './metadata/metadata-visitor';
+
+export default declare(
+  (api: any): PluginObj => {
+    api.assertVersion(7);
+
+    return {
+      visitor: {
+        Program(programPath) {
+          /**
+           * We need to traverse the program right here since
+           * `@babel/preset-typescript` removes imports at this level.
+           *
+           * Since we need to convert some typings into **bindings**, used in
+           * `Reflect.metadata` calls, we need to process them **before**
+           * the typescript preset.
+           */
+          programPath.traverse({
+            ClassDeclaration(path) {
+              for (const field of path.get('body').get('body')) {
+                if (
+                  field.type !== 'ClassMethod' &&
+                  field.type !== 'ClassProperty'
+                ) {
+                  continue;
+                }
+
+                parameterVisitor(path, field as any);
+                metadataVisitor(path, field as any);
+              }
+
+              /**
+               * We need to keep binding in order to let babel know where imports
+               * are used as a Value (and not just as a type), so that
+               * `babel-transform-typescript` do not strip the import.
+               */
+              (path.parentPath.scope as any).crawl();
+            }
+          });
+        }
+      }
+    };
+  }
+);