fix(RecordButton): Fix temporal dead zone error breaking Dashboard #13
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Move stopRecording callback definition before startRecording to fix 'Cannot access stopRecording before initialization' ReferenceError. The issue occurred because startRecording referenced stopRecording in both its function body (for maxDuration auto-stop) and its dependency array, but stopRecording was defined after startRecording. JavaScript's temporal dead zone prevents accessing const/let variables before their declaration, even within useCallback closures. This bug prevented the Dashboard example page and any component using RecordButton from rendering in Storybook.
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Pull request overview
Fixes a runtime ReferenceError (temporal dead zone) that prevented RecordButton (and the Dashboard Storybook example) from rendering by reordering hook callback definitions.
Changes:
- Moves
stopRecording’suseCallbackdefinition abovestartRecordingso it can be safely referenced instartRecording’s body and dependency array.
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| const stopRecording = React.useCallback(() => { | ||
| if (timerRef.current) { | ||
| clearInterval(timerRef.current); | ||
| } | ||
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| if ( | ||
| mediaRecorderRef.current && | ||
| mediaRecorderRef.current.state !== 'inactive' | ||
| ) { | ||
| mediaRecorderRef.current.stop(); | ||
| } | ||
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| if (streamRef.current) { | ||
| streamRef.current.getTracks().forEach((track) => track.stop()); | ||
| } | ||
| }, []); |
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Consider adding/expanding a Playwright Storybook render/visual test that covers the Dashboard story (or a RecordButton story) to prevent regressions where RecordButton fails to render due to hook callback ordering/initialization errors (this bug was only caught at runtime in Storybook).
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Move stopRecording callback definition before startRecording to fix 'Cannot access stopRecording before initialization' ReferenceError.
The issue occurred because startRecording referenced stopRecording in both its function body (for maxDuration auto-stop) and its dependency array, but stopRecording was defined after startRecording. JavaScript's temporal dead zone prevents accessing const/let variables before their declaration, even within useCallback closures.
This bug prevented the Dashboard example page and any component using RecordButton from rendering in Storybook.