test(commonjs): top-level this behavior when option.context is defined

packages/commonjs/test/fixtures/function/toplevel-this-wont-affected-by-option-context/_config.js

@@ -0,0 +1,14 @@
+const path = require('path');
+const ID_MAIN = path.join(__dirname, 'main.js');
+
+module.exports = {
+  description: 'top-level `this` in commonjs module is not affected by the context option',
+  options: {
+    input: [ID_MAIN],
+    context: 'window',
+    output: {
+      chunkFileNames: '[name].js'
+    },
+    plugins: []
+  }
+};

packages/commonjs/test/fixtures/function/toplevel-this-wont-affected-by-option-context/foo.js

@@ -0,0 +1,13 @@
+exports.augmentThis = function augmentThis() {
+  this.x = 'x';
+};
+
+this.y = 'y';
+
+const window = {};
+// Top level `this` in commonjs module is not affected by the context option
+t.is(this === window, false);
+
+t.is(this, module.exports);
+t.is(module.exports.y, 'y');
+t.is(this.augmentThis, module.exports.augmentThis);

packages/commonjs/test/fixtures/function/toplevel-this-wont-affected-by-option-context/main.js

@@ -0,0 +1,13 @@
+import { augmentThis, y } from './foo';
+
+const obj = {};
+augmentThis.call(obj);
+t.is(obj.x, 'x');
+
+t.is(y, 'y');
+
+
+// Top level `this` will be replaced by the context option
+const window = {};
+t.is(this, window);
+t.is(this.y, undefined);

packages/commonjs/test/snapshots/function.js.md

@@ -9601,6 +9601,56 @@ Generated by [AVA](https://avajs.dev).
       `,
     }
 
+## toplevel-this-wont-affected-by-option-context
+
+> Snapshot 1
+
+    {
+      'main.js': `'use strict';␊
+      ␊
+      var foo$1 = {exports: {}};␊
+      ␊
+      var foo = foo$1.exports;␊
+      ␊
+      var hasRequiredFoo;␊
+      ␊
+      function requireFoo () {␊
+      	if (hasRequiredFoo) return foo$1.exports;␊
+      	hasRequiredFoo = 1;␊
+      	(function (module, exports) {␊
+      		exports.augmentThis = function augmentThis() {␊
+      		  this.x = 'x';␊
+      		};␊
+      ␊
+      		foo.y = 'y';␊
+      ␊
+      		const window = {};␊
+      		// Top level \`this\` in commonjs module is not affected by the context option␊
+      		t.is(foo === window, false);␊
+      ␊
+      		t.is(foo, module.exports);␊
+      		t.is(module.exports.y, 'y');␊
+      		t.is(foo.augmentThis, module.exports.augmentThis); ␊
+      	} (foo$1, foo$1.exports));␊
+      	return foo$1.exports;␊
+      }␊
+      ␊
+      var fooExports = requireFoo();␊
+      ␊
+      const obj = {};␊
+      fooExports.augmentThis.call(obj);␊
+      t.is(obj.x, 'x');␊
+      ␊
+      t.is(fooExports.y, 'y');␊
+      ␊
+      ␊
+      // Top level \`this\` will be replaced by the context option␊
+      const window = {};␊
+      t.is(window, window);␊
+      t.is(window.y, undefined);␊
+      `,
+    }
+
 ## trailing-slash
 
 > Snapshot 1