Pixiv CLI Test

Test pixiv-cli

Determine the evidence

Read the diff and the affected owner/tests before choosing commands. Work from the repository root unless a command explicitly needs another directory. Check go version against go.mod; source builds need cgo and a compatible C linker plus the committed native libraries. Do not install missing tools or fetch dependencies without authorization. Report environment failures separately from regressions.

For source behavior, select the smallest existing test that exposes the missing behavior, or extend it only where coverage is missing, and observe its expected failure before implementation. A test that fails to compile or cannot reach its assertion is not a behavioral Red. Implement one slice, run Green, then refactor and rerun. For structural-only work, reuse before/after characterization evidence; obtain an explicit exception if an applicable Red requirement cannot be met. Never modify expected output solely to make an unexplained failure disappear.

Use existing Go testing and HTTP/FS fixtures. Test public behavior through real boundaries rather than reproducing the implementation in mocks. Prefer deterministic inputs and temporary stores; exercise cancellation, error propagation, and ordering when affected. Follow the canonical test file layout, including owner-matched names and documented same-package exceptions; do not create task-numbered test files or public exports only for tests.

Decide whether test code must change

Before adding a test, name the observable contract or credible failure that existing tests do not protect. Inspect their assertions, not just their names or coverage percentage. Prefer running an existing test, then extending a relevant case/table, then adding a new test only for an uncovered scenario. Record the choice briefly in the existing handoff, not a new test-plan file.

• Test behavior, not the existence of each function or file. A getter, forwarding wrapper, simple field projection, or newly extracted helper needs no separate test when its behavior is already protected at the calling boundary. Short security, parsing, or persistence code can still carry independent risk and require coverage.
• For pure moves, renames, or extraction, run existing characterization before and after. Do not invent a behavior change, alter an assertion to manufacture Red, or duplicate a test solely because a helper appeared.
• Test at the narrowest stable boundary that catches the defect. Extra CLI/MCP/SDK layers earn tests for distinct serialization, validation, permissions, or failure semantics, not repeated assertions of the same mapping. Mock real external boundaries rather than recreating the implementation in a test.
• Keep fixtures and assertions direct. Use table-driven cases only when they share setup and semantics; avoid a generic fixture builder, mock hierarchy, assertion DSL, or new framework for a small case. Do not test standard-library behavior instead of the project's own contract.
• Ordinary prose comments, headings, and internal code layout do not need exact-text or AST/regex tests. Machine-consumed directives, generated contracts, parsers, and security boundaries may need targeted existing checks; distinguish those from style preferences.
• Remove or consolidate tests only within the authorized scope and after identifying the same contract protected by retained checks. Preserve regression inputs and run the retained checks; fewer lines alone do not justify deleting evidence.

Finish adding tests when changed contracts and credible failure paths are protected. There is no per-function, per-file, test-count, or invented coverage-percentage target. TDD governs the order of evidence, not the quantity of new test code; mandatory repository gates still apply.