From 3bcdf0c23ba77cfa15f76690af939b6ae9591a3b Mon Sep 17 00:00:00 2001
From: Lukas Taegert-Atkinson <lukas.taegert-atkinson@tngtech.com>
Date: Wed, 3 May 2023 06:54:10 +0200
Subject: [PATCH] Handle shimming missing exports when preserving modules

---
 src/Module.ts                                 |  6 +++++-
 .../_config.js                                | 19 +++++++++++++++++++
 .../missing-export-preserve-modules/foo.js    |  1 +
 .../missing-export-preserve-modules/main.js   |  2 ++
 4 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 test/function/samples/missing-export-preserve-modules/_config.js
 create mode 100644 test/function/samples/missing-export-preserve-modules/foo.js
 create mode 100644 test/function/samples/missing-export-preserve-modules/main.js

diff --git a/src/Module.ts b/src/Module.ts
index 8d539ad2c90..55cec222fe9 100644
--- a/src/Module.ts
+++ b/src/Module.ts
@@ -747,7 +747,11 @@ export default class Module {
 		// Modules where this.ast is missing have been loaded via this.load and are
 		// not yet fully processed, hence they cannot be included.
 		return (
-			this.ast && (this.ast.included || this.namespace.included || this.importedFromNotTreeshaken)
+			this.ast &&
+			(this.ast.included ||
+				this.namespace.included ||
+				this.importedFromNotTreeshaken ||
+				this.exportShimVariable.included)
 		);
 	}
 
diff --git a/test/function/samples/missing-export-preserve-modules/_config.js b/test/function/samples/missing-export-preserve-modules/_config.js
new file mode 100644
index 00000000000..cd10b25726d
--- /dev/null
+++ b/test/function/samples/missing-export-preserve-modules/_config.js
@@ -0,0 +1,19 @@
+const path = require('node:path');
+
+module.exports = defineTest({
+	description: 'supports shimming missing exports when preserving modules',
+	options: {
+		shimMissingExports: true,
+		output: {
+			preserveModules: true
+		}
+	},
+	warnings: [
+		{
+			binding: 'bar',
+			code: 'SHIMMED_EXPORT',
+			exporter: path.join(__dirname, 'foo.js'),
+			message: 'Missing export "bar" has been shimmed in module "foo.js".'
+		}
+	]
+});
diff --git a/test/function/samples/missing-export-preserve-modules/foo.js b/test/function/samples/missing-export-preserve-modules/foo.js
new file mode 100644
index 00000000000..3329a7d972f
--- /dev/null
+++ b/test/function/samples/missing-export-preserve-modules/foo.js
@@ -0,0 +1 @@
+export const foo = 'foo';
diff --git a/test/function/samples/missing-export-preserve-modules/main.js b/test/function/samples/missing-export-preserve-modules/main.js
new file mode 100644
index 00000000000..352d9782b70
--- /dev/null
+++ b/test/function/samples/missing-export-preserve-modules/main.js
@@ -0,0 +1,2 @@
+import { bar } from './foo';
+assert.strictEqual(bar, undefined);