fix(patches): register the live-markdown parser worklet in an insertion effect

[dariusz-biela]

PR Stack

Follow-up to #101577, which fixed the React Native renderer so Fabric runs the insertion effect cleanup for a subtree removed while hidden. This PR carries the library change as a patch and relies on that renderer patch.

Explanation of Change

Patches @expensify/react-native-live-markdown@0.1.336 with the fix from Expensify/react-native-live-markdown#776: the parser worklet is registered in useInsertionEffect instead of during render, so the native input keeps formatting markdown after React remounts its effects. The upstream PR is on hold until the library can rely on React Native 0.88, which is why the change ships as a patch.

In the app

• MarkdownTextInput on iOS and Android keeps formatting markdown after its screen was hidden behind an <Activity> and shown again, and under StrictMode in development. Before, the input silently lost its parser and rendered plain text from then on.
• No change on web, the web input is not part of the patch.

In the code

• patches/@expensify/react-native-live-markdown/…+001+register-parser-worklet-in-insertion-effect.patch carries the src/, lib/ and native (cpp/, apple/, android/) parts of the upstream PR. The parser id is chosen in JS, one per mounted input and a fresh one on every parser change, and registered in a new useParserId hook. The native registry becomes a plain map from id to worklet. A parse for an id with no registered worklet logs a warning and returns no ranges without caching them, so the next parse picks the parser up once it is registered.
• patches/@expensify/react-native-live-markdown/details.md documents the patch and its dependency on the renderer patch from fix(patches): run the useInsertionEffect cleanup of a component removed inside a hidden Activity #101577: without it Fabric skips the insertion cleanup for an input removed while hidden and the worklet leaks in the native registry.

Note

This case is unreachable in practice, but it is possible in theory, so I'm noting it here. On a parser change or unmount, the insertion cleanup unregisters the old id during the JS commit, a moment before the native view receives the new parserId. A parse that runs on the UI thread inside that window finds no worklet, logs a No parser registered warning and returns no ranges for that single parse. The next parse formats the text again. I could not trigger it on the iOS simulator, even with fast typing right after a filter swap in the search router.

Fixed Issues

$ #98254
PROPOSAL: N/A (internal fix)

Tests

The bug is latent on main: no markdown input sits under a hidden <Activity> and StrictMode is off, so the dev steps turn on StrictMode, which disconnects and reconnects effects on every mount the same way a hidden <Activity> does. The patch changes native code, so rebuild the app after npm install.

1. Run npm install and verify that patch-package lists @expensify/react-native-live-markdown@0.1.336 (1 register-parser-worklet-in-insertion-effect) with a check mark and no warning.
2. Set USE_REACT_STRICT_MODE_IN_DEV to true in src/CONFIG.ts, rebuild and start the app on iOS and Android. Open a report and type Hello *bold* _italic_ ~strike~ `code` https://expensify.com in the composer. Verify that every style and the link render as you type. On main with the same flag the composer shows plain text only.
3. Send the message, open another report and come back. Type *again* in the composer and verify that it renders bold.
4. Open the search router, type from: and pick a person from the suggestions. Verify that the filter is highlighted. Delete the picked value, pick a different person and verify that the new filter is highlighted too. Each change gives the input a new parser, so this checks that a parser swap keeps formatting.
5. Revert src/CONFIG.ts, run the app on web and repeat step 2. Verify that formatting works as before, since the web input is not part of the patch.

• Verify that no errors appear in the JS console

Offline tests

N/A. The patch only changes when the markdown parser is registered on the native side, no network or Onyx code is involved.

QA Steps

Regression pass on the normal build, with no StrictMode and no <Activity>. Run it on iOS and Android native, and steps 1 and 2 on mWeb and desktop web.

1. Open a report and type Hello *bold* _italic_ ~strike~ `code` https://expensify.com in the composer. Add a code block, a quote (> quote), a heading (# heading), a mention of another member and an emoji. Verify that everything is formatted as you type.
2. Send the message. Verify that the composer clears and formats the next text you type.
3. Edit the sent message. Verify that the edit composer shows the formatting and keeps formatting while you change the text.
4. Go to Search, then Settings, then back to the report. Type *bold* in the composer and verify that it renders bold.
5. Open the search router, type type:expense from: and pick a person from the suggestions. Verify that both filters are highlighted, then replace the picked person and verify that the highlighting follows.

• Verify that no errors appear in the JS console

PR Author Checklist

• I linked the correct issue in the ### Fixed Issues section above
• I wrote clear testing steps that cover the changes made in this PR
  • I added steps for local testing in the Tests section
  • I added steps for the expected offline behavior in the Offline steps section
  • I added steps for Staging and/or Production testing in the QA steps section
  • I added steps to cover failure scenarios (i.e. verify an input displays the correct error message if the entered data is not correct)
  • I turned off my network connection and tested it while offline to ensure it matches the expected behavior (i.e. verify the default avatar icon is displayed if app is offline)
  • I tested this PR with a High Traffic account against the staging or production API to ensure there are no regressions (e.g. long loading states that impact usability).
• I included screenshots or videos for tests on all platforms
• I ran the tests on all platforms & verified they passed on:
  • Android: Native
  • Android: mWeb Chrome
  • iOS: Native
  • iOS: mWeb Safari
  • MacOS: Chrome / Safari
• I verified there are no console errors (if there's a console error not related to the PR, report it or open an issue for it to be fixed)
• I followed proper code patterns (see Reviewing the code)
  • I verified that comments were added to code that is not self explanatory
  • I verified that any new or modified comments were clear, correct English, and explained "why" the code was doing something instead of only explaining "what" the code was doing.
  • I verified any copy / text that was added to the app is grammatically correct in English. It adheres to proper capitalization guidelines (note: only the first word of header/labels should be capitalized), and is either coming verbatim from figma or has been approved by marketing (in order to get marketing approval, ask the Bug Zero team member to add the Waiting for copy label to the issue)
• If a new code pattern is added I verified it was agreed to be used by multiple Expensify engineers
• I followed the guidelines as stated in the Review Guidelines
• I tested other components that can be impacted by my changes (i.e. if the PR modifies a shared library or component like Avatar, I verified the components using Avatar are working as expected)
• If a new CSS style is added I verified that:
  • A similar style doesn't already exist
  • The style can't be created with an existing StyleUtils function (i.e. StyleUtils.getBackgroundAndBorderStyle(theme.componentBG))
• If new assets were added or existing ones were modified, I verified that:
  • The assets are optimized and compressed (for SVG files, run npm run compress-svg)
  • The assets load correctly across all supported platforms.
• If the PR modifies code that runs when editing or sending messages, I tested and verified there is no unexpected behavior for all supported markdown - URLs, single line code, code blocks, quotes, headings, bold, strikethrough, and italic.
• If the PR modifies a generic component, I tested and verified that those changes do not break usages of that component in the rest of the App (i.e. if a shared library or component like Avatar is modified, I verified that Avatar is working as expected in all cases)
• If the PR modifies a component related to any of the existing Storybook stories, I tested and verified all stories for that component are still working as expected.
• If the PR modifies a component or page that can be accessed by a direct deeplink, I verified that the code functions as expected when the deeplink is used - from a logged in and logged out account.
• If the PR modifies the UI (e.g. new buttons, new UI components, changing the padding/spacing/sizing, moving components, etc) or modifies the form input styles:
  • I verified that all the inputs inside a form are aligned with each other.
  • I added Design label and/or tagged @Expensify/design so the design team can review the changes.
• I added unit tests for any new feature or bug fix in this PR to help automatically prevent regressions in this user flow.
• If the main branch was merged into this PR after a review, I tested again and verified the outcome was still expected according to the Test steps.

Screenshots/Videos

Android: Native

iOS: Native

Dev tests:

3-tests-ios-markdown-formatting.mp4

QA tests:

4-qa-steps-ios-markdown-formatting.mp4

MacOS: Chrome / Safari

Dev tests:

1-tests-web-markdown-formatting.mp4

QA tests:

2-qa-steps-web-markdown-formatting.mp4

[github-actions]

⚠️ This PR is possibly changing native code and/or updating libraries, it may cause problems with HybridApp. Please check if any patch updates are required in the HybridApp repo and run an AdHoc build to verify that HybridApp will not break. Ask Contributor Plus for help if you are not sure how to handle this. ⚠️