test: add spec

test/spec/on-image-error-handler.spec.ts

@@ -0,0 +1,29 @@
+import { embedImages } from '../../src/embed-images'
+
+describe('Error Handling in resourceToDataURL', () => {
+  it('should call the onImageErrorHandler when an error occurs', async () => {
+    const handlers = {
+      onError: () => {},
+    }
+    spyOn(handlers, 'onError')
+    const options = { onImageErrorHandler: handlers.onError }
+    const node = document.createElement('img')
+    node.src = 'invalid_url'
+
+    // Assuming resourceToDataURL is the function being tested
+    await embedImages(node, options).then(() => {
+      expect(handlers.onError).toHaveBeenCalled()
+    })
+  })
+
+  it('should reject with an error if no onImageErrorHandler is provided', async () => {
+    const options = {}
+    const node = document.createElement('img')
+    node.src = 'invalid_url'
+    await embedImages(node, options).catch((error) => {
+      expect(() => {
+        throw error
+      }).toThrow()
+    })
+  })
+})