testing.md

Testing and verify

bun test
bun run test:watch
bun verify

verify = oxlint + oxfmt --check + tsc + tsc:app + Jest (212 tests as of 2026-08-22).

Tests live in src/tests/. Native modules are stubbed in jest.setup.js (AsyncStorage, FlashList → FlatList, expo-updates, safe area, etc.).

Philosophy

Focus on store/session correctness for every math mode the app exposes, plus critical UI wiring — not full visual snapshot coverage. Calculator and bitwise behavior are tested by driving the Zustand store (sessionTestHarness.ts) the same way keypad actions would.

Test files

File	What it covers
intMath.test.ts	mask/range/parse/display/copy for all bases and word sizes
mathModes.test.ts	Parametrized calc + bitwise matrix (bases × word sizes × signed)
calcSession.test.ts	Calc keypad sequences, precedence, overflow, history on =
bitwiseSession.test.ts	NOT/shift/NEG, AND/OR/XOR, hex entry, bit grid, word size
settingsSession.test.ts	Theme/defaults persistence, loadSettings, resetApp, URL constants
history.test.ts	AsyncStorage load/save, per-category cap (300), total cap (600)
settingsUi.test.tsx	Settings → History nav, Linking.openURL, History FlashList rows
bootstrapApp.test.ts	OTA sync then loadSettings order
App.test.tsx	Splash + bootstrapApp on mount
updatesController.test.ts	OTA check/fetch/skip/fail paths (mocked expo-updates)
storeVersion.test.ts	Installed version helper
theme.test.ts	Light/dark semantic tokens
appStore.test.ts	Store wiring smoke
CustomSplashScreen.test.tsx	Splash backgrounds

Calculator — scenario samples (calcSession.test.ts)

Store-driven tests (calcKeys.press(...)) with 8-bit signed — representative flows; the full mode matrix is in mathModes.test.ts + intMath.test.ts:

Scenario	Input / action	Expected
Basic add	10+1=	value 11, history entry
Precedence	2+3×4=	14
Parentheses	(2+3)×4=	20
Auto-close paren	(5+2=	7
Hex base	base 16, 2A+1=	43
Word mask	200+100=	44
Signed overflow	127+1=	128, lastOverflow true
Sticky overflow	127+1−1=	127, overflow stays true
Intermediate fold	80×4÷4=	16, overflow true
Divide by zero	5÷0=	divError, value 0
Incomplete	5+ then =	toast “Incomplete expression”
AC	after eval	tokens [], value 0
Backspace	123 ⌫ then =	12
Ans	5+5= then +Ans=	20
Cross-tab	calc 15= then bitwise NOT	shared value updated

Controller unit tests (applyEvaluate, tapDigit, tapOp, tapAC, tapAns, tapBack) cover div-zero patch, 255×255 mask, and intermediate folding.

Calculator — mode matrix (mathModes.test.ts + intMath.test.ts)

Mode	Covered
Input bases DEC/BIN/OCT/HEX	Yes
Word sizes 8 / 16 / 32 / 64	Yes
Signed overflow at max + 1	Yes
Unsigned wrap at max + 1	Yes
Mixed-base expressions	Yes
Unary minus	Yes
Ans in hex	Yes
Word shrink mid-session	Yes
Empty evaluate	Yes

Calculator — remaining non-math gaps

Gap	Notes
Clipboard copy (BaseRows)	formatCopyValue covered in intMath; UI press not mocked
Full CalculatorScreen render	Optional smoke

Bitwise — covered inputs / expected results

Scenario	Action	Expected
NOT	seed 111 → NOT	0x90
SHL overflow	0x80 SHL	overflow, value 0
SHR	after SHL overflow	overflow cleared
NEG at −128	0x80 NEG	overflow, value 0x80
AND/OR/XOR	F0 op 0F	0, 0xFF, 0xF0 respectively
Pending op switch	AND → OR mid-entry	pending OR, value unchanged
Hex → operand	FF AND 0F	operand 0x0F
Hex overflow	1FF on 8-bit	toast Max 8-bit
Bit toggle	bit 0 on 0	value 1
Bit toggle + pending op	F0 AND toggle bit 0	operand 1, value F0
Word shrink	16-bit 0x1FF → 8-bit	0xFF, mask toast
Cross-tab	calc 10= OR 5	15

Bitwise — mode matrix (mathModes.test.ts)

Mode	Covered
Word sizes 8 / 16 / 32 / 64	Yes
NOT / SHL / SHR / NEG per word size	Yes
AND / OR / XOR per word size	Yes
Top-bit toggle per word size	Yes
Hex entry overflow per word size	Yes
Calc ↔ bitwise shared value per size	Yes

Bitwise — remaining non-math gaps

Gap	Notes
operandWarn UI toast	Store flag tested; UI not mocked
BitwiseScreen render	Optional smoke

Settings / history / boot

Area	Covered	Gap
Theme persist + reset preserves light	Yes	Save failure toast
Launch defaults → session on loadSettings	Yes	Corrupt JSON in storage
History caps	Yes	UI empty states (only via buildHistoryListRows in settings test)
Settings UI → History nav	Yes (mocked navigation)	Full stack integration without mocks
External URLs	Yes	Linking failure toast
bootstrapApp order	Yes	—

OTA / app shell

Area	Covered	Gap
syncOtaUpdate paths	Yes	—
App splash + bootstrap	Yes	SPLASH_MIN_MS timing edge
Custom splash theme	Yes	—

Summary

Math correctness is tested at the store + intMath layer for every user-facing mode: all four calc input bases, all four word sizes, signed and unsigned overflow semantics, all bitwise unary/binary ops, mixed-base expressions, and calc ↔ bitwise value sharing — each with explicit expected numeric answers.

Still outside the math gate: clipboard button wiring (formatting logic is tested), corrupt storage, and unmocked navigation. Those do not affect evaluated results.

Release gate: bun verify (212 tests).