`react-doctor/no-floating-then-in-jsx-handler`

Floating .then in a JSX event handler

Category: Bugs
Severity: warn
Source: oxlint-plugin-react-doctor
Framework: global
Enabled when: always
Default: Enabled

Validate the diagnostic

Confirm the reported code matches this rule before you edit it.

Confirm the reported code matches react-doctor/no-floating-then-in-jsx-handler. Compare it with the Before example and verify the same API, framework, and execution context. Treat it as a false positive only when one of those conditions differs.

Compare the code

The corrected pattern shows a focused way to address the diagnostic.

Reported pattern

const SaveButton = () => (
  <button onClick={() => save().then(showSuccess)}>
    Save
  </button>
);

Corrected pattern

const SaveButton = () => (
  <button
    onClick={() => save().then(showSuccess).catch(showError)}
  >
    Save
  </button>
);

How to fix

Use the corrected pattern as a reference. Preserve behavior that the rule does not require you to change.

Copyable fix prompt

Copy this self-contained prompt into your coding agent after you confirm the diagnostic.

Fix every confirmed react-doctor/no-floating-then-in-jsx-handler diagnostic in the current repository. Required change: - Handle every event-handler promise rejection. Add .catch(), or use an async handler with try/catch. Error boundaries do not catch rejected event-handler promises.

Reference transformation:Before:

const SaveButton = () => (
  <button onClick={() => save().then(showSuccess)}>
    Save
  </button>
);

After:

const SaveButton = () => (
  <button
    onClick={() => save().then(showSuccess).catch(showError)}
  >
    Save
  </button>
);

Constraints: - Confirm the reported code matches the Before pattern. - Make the smallest change that fixes the root cause. - Preserve behavior and interfaces unrelated to this diagnostic. - Reuse existing project components, utilities, and conventions. - Do not introduce render-phase side effects, render-phase state updates, or Hooks rule violations. - Adapt identifiers and framework details instead of copying blindly. - Do not disable the rule or suppress matching code. Verification: - Run focused tests for the changed behavior. - Run React Doctor and confirm this diagnostic no longer appears. - Report the files changed and any checks you could not run.

More Bugs rules from the rules reference:

react-doctor/no-hydration-branch-on-browser-global: Render the same initial branch on the server and client instead of branching on a browser global during hydration.
react-doctor/no-impure-call-at-module-scope: Nondeterministic built-in at module scope
react-doctor/no-impure-state-updater: State updater has side effects
react-doctor/no-indeterminate-attribute: Indeterminate checkbox state set as an attribute
react-doctor/no-inert-sticky-position: Sticky positioning has no inset

react-doctor/no-floating-then-in-jsx-handler