diff --git a/test/cli/samples/warn-broken-sourcemap/_config.js b/test/cli/samples/warn-broken-sourcemap/_config.js
index 596a4d33ae5..160b7876918 100644
--- a/test/cli/samples/warn-broken-sourcemap/_config.js
+++ b/test/cli/samples/warn-broken-sourcemap/_config.js
@@ -12,7 +12,7 @@ module.exports = {
 			stderr,
 			'(!) Broken sourcemap\n' +
 				'https://rollupjs.org/guide/en/#warning-sourcemap-is-likely-to-be-incorrect\n' +
-				"Plugins that transform code (such as 'test-plugin1', 'test-plugin2' and 'test-plugin3') should generate accompanying sourcemaps"
+				"Plugins that transform code (such as 'test-plugin1') should generate accompanying sourcemaps\n"
 		);
 	}
 };
diff --git a/test/cli/samples/warn-broken-sourcemap/rollup.config.js b/test/cli/samples/warn-broken-sourcemap/rollup.config.js
index c490546377b..d29788efcb6 100644
--- a/test/cli/samples/warn-broken-sourcemap/rollup.config.js
+++ b/test/cli/samples/warn-broken-sourcemap/rollup.config.js
@@ -6,18 +6,6 @@ module.exports = {
 			transform(code) {
 				return code + '/*1*/';
 			}
-		},
-		{
-			name: 'test-plugin2',
-			transform(code) {
-				return code + '/*2*/';
-			}
-		},
-		{
-			name: 'test-plugin3',
-			transform(code) {
-				return code + '/*3*/';
-			}
 		}
 	],
 	output: {
diff --git a/test/cli/samples/warn-broken-sourcemaps/_config.js b/test/cli/samples/warn-broken-sourcemaps/_config.js
new file mode 100644
index 00000000000..596a4d33ae5
--- /dev/null
+++ b/test/cli/samples/warn-broken-sourcemaps/_config.js
@@ -0,0 +1,18 @@
+const fs = require('fs');
+const path = require('path');
+const { assertStderrIncludes } = require('../../../utils.js');
+
+module.exports = {
+	description: 'displays warnings for broken sourcemaps',
+	command: 'rollup -c',
+	stderr: stderr => {
+		fs.unlinkSync(path.resolve(__dirname, 'bundle'));
+		fs.unlinkSync(path.resolve(__dirname, 'bundle.map'));
+		assertStderrIncludes(
+			stderr,
+			'(!) Broken sourcemap\n' +
+				'https://rollupjs.org/guide/en/#warning-sourcemap-is-likely-to-be-incorrect\n' +
+				"Plugins that transform code (such as 'test-plugin1', 'test-plugin2' and 'test-plugin3') should generate accompanying sourcemaps"
+		);
+	}
+};
diff --git a/test/cli/samples/warn-broken-sourcemaps/main.js b/test/cli/samples/warn-broken-sourcemaps/main.js
new file mode 100644
index 00000000000..c0b933d7b56
--- /dev/null
+++ b/test/cli/samples/warn-broken-sourcemaps/main.js
@@ -0,0 +1 @@
+console.log('main');
diff --git a/test/cli/samples/warn-broken-sourcemaps/rollup.config.js b/test/cli/samples/warn-broken-sourcemaps/rollup.config.js
new file mode 100644
index 00000000000..c490546377b
--- /dev/null
+++ b/test/cli/samples/warn-broken-sourcemaps/rollup.config.js
@@ -0,0 +1,28 @@
+module.exports = {
+	input: 'main.js',
+	plugins: [
+		{
+			name: 'test-plugin1',
+			transform(code) {
+				return code + '/*1*/';
+			}
+		},
+		{
+			name: 'test-plugin2',
+			transform(code) {
+				return code + '/*2*/';
+			}
+		},
+		{
+			name: 'test-plugin3',
+			transform(code) {
+				return code + '/*3*/';
+			}
+		}
+	],
+	output: {
+		format: 'esm',
+		file: 'bundle',
+		sourcemap: true
+	}
+};
diff --git a/test/form/samples/default-export-mode/_config.js b/test/form/samples/default-export-mode/_config.js
new file mode 100644
index 00000000000..bc4638b956c
--- /dev/null
+++ b/test/form/samples/default-export-mode/_config.js
@@ -0,0 +1,9 @@
+module.exports = {
+	description: 'allows specifying the export mode to be "default"',
+	options: {
+		output: {
+			exports: 'default',
+			name: 'bundle'
+		}
+	}
+};
diff --git a/test/form/samples/default-export-mode/_expected/amd.js b/test/form/samples/default-export-mode/_expected/amd.js
new file mode 100644
index 00000000000..37d25711e09
--- /dev/null
+++ b/test/form/samples/default-export-mode/_expected/amd.js
@@ -0,0 +1,7 @@
+define(function () { 'use strict';
+
+	var main = 42;
+
+	return main;
+
+});
diff --git a/test/form/samples/default-export-mode/_expected/cjs.js b/test/form/samples/default-export-mode/_expected/cjs.js
new file mode 100644
index 00000000000..5a370cdb174
--- /dev/null
+++ b/test/form/samples/default-export-mode/_expected/cjs.js
@@ -0,0 +1,5 @@
+'use strict';
+
+var main = 42;
+
+module.exports = main;
diff --git a/test/form/samples/default-export-mode/_expected/es.js b/test/form/samples/default-export-mode/_expected/es.js
new file mode 100644
index 00000000000..d862de816a3
--- /dev/null
+++ b/test/form/samples/default-export-mode/_expected/es.js
@@ -0,0 +1,3 @@
+var main = 42;
+
+export default main;
diff --git a/test/form/samples/default-export-mode/_expected/iife.js b/test/form/samples/default-export-mode/_expected/iife.js
new file mode 100644
index 00000000000..3578ebdc148
--- /dev/null
+++ b/test/form/samples/default-export-mode/_expected/iife.js
@@ -0,0 +1,8 @@
+var bundle = (function () {
+	'use strict';
+
+	var main = 42;
+
+	return main;
+
+}());
diff --git a/test/form/samples/default-export-mode/_expected/system.js b/test/form/samples/default-export-mode/_expected/system.js
new file mode 100644
index 00000000000..6d902c53457
--- /dev/null
+++ b/test/form/samples/default-export-mode/_expected/system.js
@@ -0,0 +1,10 @@
+System.register('bundle', [], function (exports) {
+	'use strict';
+	return {
+		execute: function () {
+
+			var main = exports('default', 42);
+
+		}
+	};
+});
diff --git a/test/form/samples/default-export-mode/_expected/umd.js b/test/form/samples/default-export-mode/_expected/umd.js
new file mode 100644
index 00000000000..5e071cb1060
--- /dev/null
+++ b/test/form/samples/default-export-mode/_expected/umd.js
@@ -0,0 +1,11 @@
+(function (global, factory) {
+	typeof exports === 'object' && typeof module !== 'undefined' ? module.exports = factory() :
+	typeof define === 'function' && define.amd ? define(factory) :
+	(global = global || self, global.bundle = factory());
+}(this, (function () { 'use strict';
+
+	var main = 42;
+
+	return main;
+
+})));
diff --git a/test/form/samples/default-export-mode/main.js b/test/form/samples/default-export-mode/main.js
new file mode 100644
index 00000000000..7a4e8a723a4
--- /dev/null
+++ b/test/form/samples/default-export-mode/main.js
@@ -0,0 +1 @@
+export default 42;
diff --git a/test/function/samples/invalid-default-export-mode/_config.js b/test/function/samples/invalid-default-export-mode/_config.js
new file mode 100644
index 00000000000..b7a6e6994cf
--- /dev/null
+++ b/test/function/samples/invalid-default-export-mode/_config.js
@@ -0,0 +1,14 @@
+module.exports = {
+	solo: true,
+	description: 'throw for invalid default export mode',
+	options: {
+		output: {
+			exports: 'default'
+		}
+	},
+	generateError: {
+		code: 'INVALID_EXPORT_OPTION',
+		message:
+			'"default" was specified for "output.exports", but entry module "main.js" has the following exports: default, foo'
+	}
+};
diff --git a/test/function/samples/invalid-default-export-mode/main.js b/test/function/samples/invalid-default-export-mode/main.js
new file mode 100644
index 00000000000..8981df90477
--- /dev/null
+++ b/test/function/samples/invalid-default-export-mode/main.js
@@ -0,0 +1,2 @@
+export default 42;
+export const foo = 43;