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chore(site): enable noUncheckedIndexedAccess TypeScript option#21383

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chore(site): enable noUncheckedIndexedAccess TypeScript option#21383

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mtojek commentedDec 23, 2025

Description

This PR enables thenoUncheckedIndexedAccess TypeScript compiler option assuggested by @Emyrk.

This option makes array/object indexed access returnT | undefined instead ofT, improving type safety by ensuring we properly handle cases where indexed access might return undefined.

Progress

Status	Count
Original errors	257
Fixed	125
Remaining	132

Error Breakdown (Original 257)

Error Code	Count	Description
TS2532	86	Object is possibly 'undefined'
TS2345	62	Argument type mismatch with undefined
TS2322	56	Type assignment with undefined
TS18048	46	Variable possibly undefined
Other	7	(TS2538, TS2339, TS2769, TS2488)

Remaining Work

The 132 remaining errors are primarily in:

Test files (.jest.tsx,.test.ts)
Storybook stories (.stories.tsx)
Some production code inpages/

Most fixes involve adding:

Non-null assertion (!) where we're certain the value exists
Optional chaining (?.) where appropriate
Guard clauses for genuine undefined checks

Why This Change?

Before this option, TypeScript would assume indexed access always succeeds:

constitem=array[0];// Type: T (assumed to exist)item.property;// No error, but could crash at runtime!

After this option:

constitem=array[0];// Type: T | undefined (safer)item.property;// Error! Must check firstif(item){item.property;// OK}

⚠️Draft PR - This is a work in progress. The remaining 132 errors need to be fixed before this can be merged.

chore(site): enable noUncheckedIndexedAccess TypeScript option

bd0e12a

This enables the 'noUncheckedIndexedAccess' compiler option which makesarray/object indexed access return 'T | undefined' instead of 'T'.This change improves type safety by ensuring we properly handle caseswhere indexed access might return undefined.Progress:- Fixed 125 out of 257 original TypeScript errors- 132 errors remaining (mostly in test/story files)The remaining errors are primarily in:- Test files (.jest.tsx, .test.ts)- Storybook stories (.stories.tsx)- Some production code in pages/Ref:#21381 (comment)