[Test Improver] Add 116 unit tests for untested string.js utilities

[github-actions]

🤖 Test Improver — automated AI assistant

Goal and Rationale

shell/utils/string.js is a large (407-line) utility module used extensively across the codebase. Despite its size and importance, roughly half its exported functions had no unit tests. This PR adds tests for 25 previously untested pure functions.

Approach

Added shell/utils/__tests__/string-utils.test.ts with 116 tests covering:

Function	Cases
camelToTitle	simple, multi-hump, empty, null
ucFirst / lcFirst	upper/lower, already correct, empty, null
strPad	left/right padding, already-at-length, custom chars
escapeHtml	&, <>, ", ', plain
escapeRegex	dots, brackets, all specials
formatPercent	<1%, 1–10%, ≥10%, precision edge cases
pluralize	consonant+y, vowel+y, -ics, -s, regular
indent	string, array, custom token, null, afterRegex
decamelize / dasherize	camel, underscore, spaces
asciiLike	ASCII, tab, newline, non-ASCII, empty
coerceStringTypeToScalarType	float, int, boolean, NaN, passthrough
ensureRegex	regex passthrough, exact string, non-exact
matchesSomeRegex	match, no match, empty list, null string
nlToBr	LF, CR+LF, CR, HTML escaping, null
splitObjectPath	dotted, double-quoted, single-quoted, single
joinObjectPath	simple, dot-containing segment, single
shortenedImage	docker.io prefix, index.docker.io, :latest, sha256, null
isIpv4	valid, boundaries, out-of-range, too few octets, hostname
sanitizeKey / sanitizeValue / sanitizeIP	allowed chars, strips invalid, null
xOfy	numbers, non-number x/y, both
isBase64	valid, invalid padding, empty, non-base64

Coverage Impact

Running both string.test.ts (existing) and string-utils.test.ts (new):

Metric	Before	Combined
Statements	0% (new file)	89.4%
Branches	0% (new file)	98.2%
Functions	0% (new file)	88.2%
Lines	0% (new file)	89.4%

Remaining uncovered functions are non-deterministic (random32, randomStr, generateRandomAlphaString) and DOM-dependent (decodeHtml) — already covered in string.test.ts.

Trade-offs

• Created a separate file rather than modifying the existing string.test.ts (per AGENTS.md: never overwrite existing test files).
• Random functions intentionally excluded — non-deterministic by nature.

Reproducibility

# Run new tests only
node_modules/.bin/jest --no-coverage shell/utils/__tests__/string-utils.test.ts

# Run with coverage (both files)
node_modules/.bin/jest --collectCoverage --coverageDirectory /tmp/cov \
  --collectCoverageFrom 'shell/utils/string.js' \
  shell/utils/__tests__/string.test.ts \
  shell/utils/__tests__/string-utils.test.ts

Test Status

✅ 116/116 tests pass
✅ ESLint: 0 warnings, 0 errors

Warning

Firewall blocked 1 domain

The following domain was blocked by the firewall during workflow execution:

• download.cypress.io

To allow these domains, add them to the network.allowed list in your workflow frontmatter:

network:
  allowed:
    - defaults
    - "download.cypress.io"

See Network Configuration for more information.

Generated by Daily Test Improver · ● 2.4M · ◷