1 files changed, 44 insertions, 0 deletions
diff --git a/spec/frontend/editor/editor_lite_extension_base_spec.js b/spec/frontend/editor/editor_lite_extension_base_spec.js
new file mode 100644
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+++ b/spec/frontend/editor/editor_lite_extension_base_spec.js
@@ -0,0 +1,44 @@
+import { ERROR_INSTANCE_REQUIRED_FOR_EXTENSION } from '~/editor/constants';
+import { EditorLiteExtension } from '~/editor/editor_lite_extension_base';
+
+describe('The basis for an Editor Lite extension', () => {
+  let ext;
+  const defaultOptions = { foo: 'bar' };
+
+  it.each`
+    description                                                     | instance     | options
+    ${'accepts configuration options and instance'}                 | ${{}}        | ${defaultOptions}
+    ${'leaves instance intact if no options are passed'}            | ${{}}        | ${undefined}
+    ${'does not fail if both instance and the options are omitted'} | ${undefined} | ${undefined}
+    ${'throws if only options are passed'}                          | ${undefined} | ${defaultOptions}
+  `('$description', ({ instance, options } = {}) => {
+    const originalInstance = { ...instance };
+
+    if (instance) {
+      if (options) {
+        Object.entries(options).forEach(prop => {
+          expect(instance[prop]).toBeUndefined();
+        });
+        // Both instance and options are passed
+        ext = new EditorLiteExtension({ instance, ...options });
+        Object.entries(options).forEach(([prop, value]) => {
+          expect(ext[prop]).toBeUndefined();
+          expect(instance[prop]).toBe(value);
+        });
+      } else {
+        ext = new EditorLiteExtension({ instance });
+        expect(instance).toEqual(originalInstance);
+      }
+    } else if (options) {
+      // Options are passed without instance
+      expect(() => {
+        ext = new EditorLiteExtension({ ...options });
+      }).toThrow(ERROR_INSTANCE_REQUIRED_FOR_EXTENSION);
+    } else {
+      // Neither options nor instance are passed
+      expect(() => {
+        ext = new EditorLiteExtension();
+      }).not.toThrow();
+    }
+  });
+});