build: es6 compatibiliy for commonjs bundle (#74)

unjs · Aug 21, 2023 · 625f12d · 625f12d
1 parent afd1489
commit 625f12d
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Showing 3 changed files with 255 additions and 0 deletions.
diff --git a/build.config.ts b/build.config.ts
@@ -1,4 +1,6 @@
 import { defineBuildConfig } from "unbuild";
+import type { Plugin, OutputChunk } from "rollup";
+import { transform } from "esbuild";
 
 export default defineBuildConfig({
   declaration: true,
@@ -9,4 +11,21 @@ export default defineBuildConfig({
     },
   },
   entries: ["src/index"],
+  hooks: {
+    "rollup:options"(ctx, rollupConfig) {
+      (rollupConfig.plugins as Plugin[]).push({
+        name: "compat",
+        async generateBundle(_options, bundle) {
+          const cjsEntry = bundle["index.cjs"] as OutputChunk;
+          if (!cjsEntry) {
+            return;
+          }
+          cjsEntry.code = await transform(cjsEntry.code, {
+            target: "es6",
+            minify: true,
+          }).then((r) => r.code);
+        },
+      } satisfies Plugin);
+    },
+  },
 });
diff --git a/package.json b/package.json
@@ -32,10 +32,12 @@
     "@types/node": "^20.5.0",
     "@vitest/coverage-v8": "^0.34.2",
     "changelogen": "^0.5.4",
+    "esbuild": "^0.19.2",
     "eslint": "^8.47.0",
     "eslint-config-unjs": "^0.2.1",
     "jiti": "^1.19.2",
     "prettier": "^3.0.2",
+    "rollup": "^3.28.0",
     "typescript": "^5.1.6",
     "unbuild": "^2.0.0-rc.0",
     "vitest": "^0.34.2"