[TEST] Add BATS tests for eslint.sh

[prog-time]

Note

The task was generated using the MCP server — prog-time/github-issues-server

Release: 1
Type: test
Priority: high
Blocks: —
Blocked by: —
Status: todo

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Description

The script scripts/shell/linters/eslint.sh has no corresponding BATS test file. Every other linter script in scripts/shell/linters/ has a test counterpart in tests/linters/ (hadolint, htmlhint, markdownlint, shellcheck, stylelint, yamllint), but eslint.bats does not exist. This violates the project rule that every shell script must be covered by a BATS unit test (rules/process/ci-cd.md, section 9).

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Motivation

Without tests, regressions in eslint.sh — config discovery logic, file collection, the ERROR_FOUND accumulator — will not be caught by CI. ESLint's config file detection is the most complex of all linter scripts: it checks seven possible filename variants (eslintrc.json, eslint.config.js, and five others). This logic is especially brittle without test coverage.

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Target Structure

tests/
└── linters/
    ├── eslint.bats         ← new file
    ├── hadolint.bats
    ├── htmlhint.bats
    ├── markdownlint.bats
    ├── shellcheck.bats
    ├── stylelint.bats
    └── yamllint.bats

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Checklist

• Create tests/linters/eslint.bats modelled on tests/linters/htmlhint.bats
• Test: no ESLint config file found → exit 1, output contains ::error::No ESLint config file found
• Test: config .eslintrc.json found, no JS/TS files → exit 0, output contains ⚠️ No JS/TS files found. Skipping.
• Test: config eslint.config.js found (alternative format), all files pass → exit 0, output contains ✅ All JS/TS files passed ESLint checks!
• Test: config found, one file fails → exit 1, output contains ❌ ESLint found issues!
• Test: config found, multiple files, one fails — all files are checked (accumulator pattern, does not stop on first error)
• Verify the test file uses helpers from tests/helpers/common.bash (mock_tool / conditional stub pattern matching htmlhint.bats)
• Run bats tests/linters/eslint.bats locally — all tests pass
• Run bats --recursive tests/ — the full test suite passes

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Affected Files

File	Change
tests/linters/eslint.bats	create