Skip events that already have default prevented

Author: dgreif

src/index.ts

@@ -105,7 +105,7 @@ function getMatches(el: HTMLElement): RemoteFormHandler[] {
 }
 
 function handleSubmit(event: Event) {
-  if (!(event.target instanceof HTMLFormElement)) {
+  if (!(event.target instanceof HTMLFormElement) || event.defaultPrevented) {
     return
   }
   const form = event.target

test/test.js

@@ -139,4 +139,20 @@ describe('remoteForm', function () {
     button.form.action += '?a=b'
     button.click()
   })
+
+  it('does not submit the request if default is already prevented', function () {
+    // prevent default before this event reaches the remote-form listener
+    const defaultPreventHandler = event => event.preventDefault()
+    document.addEventListener('submit', defaultPreventHandler, {capture: true})
+
+    let handlerCalled = false
+    remoteForm('.my-remote-form', async function () {
+      handlerCalled = true
+    })
+
+    document.querySelector('button[type=submit]').click()
+
+    assert.isFalse(handlerCalled)
+    document.removeEventListener('submit', defaultPreventHandler, {capture: true})
+  })
 })