diff --git a/tests/src/core/importType.js b/tests/src/core/importType.js
index 6de32168d5..400c96b967 100644
--- a/tests/src/core/importType.js
+++ b/tests/src/core/importType.js
@@ -227,8 +227,13 @@ describe('importType(name)', function () {
 
   it('`isExternalModule` works with windows directory separator', function() {
     expect(isExternalModule('foo', {}, 'E:\\path\\to\\node_modules\\foo')).to.equal(true)
+    expect(isExternalModule('foo', {}, '.\\foo')).to.equal(false)
+
     expect(isExternalModule('foo', {
       'import/external-module-folders': ['E:\\path\\to\\node_modules'],
     }, 'E:\\path\\to\\node_modules\\foo')).to.equal(true)
+    expect(isExternalModule('foo', {
+      'import/external-module-folders': ['E:\\path\\to\\node_modules'],
+    }, '.\\foo')).to.equal(false)
   })
 })