# Fill output test coverage gaps — exact-width boundary and head lines_omitted

## Execution State

- **Executor Type:** any
- **Actor:** null
- **Claimed At:** null
- **Reopen Count:** 0
- **State:** ✅ (Completed)
- **Closes:** null
- **Blocked Reason:** null
- **Dir:** .
- **Validated By:** author-inline (pre-MAAV historic — see ## Verification Record)
- **Validation Date:** 2026-05-17

## Goal

Add the two pending test functions identified in the output processing test surface audit to `tests/output.rs`, so that FT-11 (exact-width boundary non-truncation) and FT-12 (process_output head limit reports accurate lines_omitted count) are covered by automated tests (Motivated: the audit of `tests/docs/feature/01_output_processing.md` found FT-11 and FT-12 marked ⏳ — the boundary-detection fix and the head/lines_omitted interaction were documented in spec but had no corresponding test, leaving regressions undetectable; Observable: two new test functions `width_exact_boundary` and `process_output_head_lines_omitted` exist in `tests/output.rs`, confirmed by `grep -c "fn width_exact_boundary\|fn process_output_head_lines_omitted" /home/user1/pro/lib/wip_core/wtools/dev/module/core/cli_fmt/tests/output.rs`; Scoped: `tests/output.rs` only — no changes to source, docs, or other test files; Testable: `cargo nextest run --manifest-path /home/user1/pro/lib/wip_core/wtools/dev/module/core/cli_fmt/Cargo.toml --features output --test output 2>&1 | tail -3`).

The boundary-detection fix (BUG-005, documented at top of `tests/output.rs`) ensures that a line whose visible length equals `max_width` is not truncated. The existing test `width_no_truncation_needed` covers a well-below-width case (10 chars, width=50) but not the exact-boundary case (10 chars, width=10), which is where the pre-fix bug manifested.

The `lines_omitted` accuracy for the `with_head()` path is verified by `combined_head_and_width` only indirectly (head=2 + 4 lines = lines_omitted=2). FT-12 requires a clean, width-free case: 5-line input, head=2, lines_omitted must be 3.

## In Scope

- `/home/user1/pro/lib/wip_core/wtools/dev/module/core/cli_fmt/tests/output.rs` — add `width_exact_boundary` and `process_output_head_lines_omitted` test functions

## Out of Scope

- Documentation updates (already completed)
- Source code changes — all tests must pass against the current `src/output.rs` without modification
- Any changes to `src/help.rs`, `tests/help.rs`, or the `cli_help_template` feature

## Requirements

- All work must strictly adhere to all applicable rulebooks
  (discover via `kbase .rulebooks`)
- 2-space indentation per code_style.rulebook.md
- Tests must be in the existing `tests/output.rs` integration test file
- No mocking — use real `process_output()` and real `OutputConfig`
- Tests must fail loudly with descriptive `assert!` messages
- Test function names must exactly match those referenced in `tests/docs/feature/01_output_processing.md`: `width_exact_boundary`, `process_output_head_lines_omitted`

## Work Procedure

Execute in order. Do not skip or reorder steps.

1. **Read spec** — Read `/home/user1/pro/lib/wip_core/wtools/dev/module/core/cli_fmt/tests/docs/feature/01_output_processing.md` §FT-11 and §FT-12 for the exact Given/When/Then for each test.
2. **Read source** — Read `/home/user1/pro/lib/wip_core/wtools/dev/module/core/cli_fmt/tests/output.rs` to understand existing test structure and placement conventions (sections, doc comments).
3. **Write `width_exact_boundary`** — In the "Width truncation tests" section, add a test: input `"0123456789"` (10 visible chars), `with_width(10)`, assert `result.width_truncated == false` and `result.content.starts_with("0123456789")`.
4. **Write `process_output_head_lines_omitted`** — In the "Head truncation tests" section (or after it), add a test: 5-line input, `with_head(2)`, assert `result.content` contains `"line1"` and `"line2"`, assert `result.lines_omitted == 3`.
5. **Validate** — Run `cargo nextest run --manifest-path /home/user1/pro/lib/wip_core/wtools/dev/module/core/cli_fmt/Cargo.toml --features output --test output 2>&1 | tail -5`. All tests must pass.
6. **Update spec status** — In `tests/docs/feature/01_output_processing.md`, remove the ⏳ marks from FT-11 and FT-12; in `tests/docs/feature/readme.md`, change `01_output_processing.md` status from ⏳ back to ✅.
7. **Walk Validation Checklist** — every item must answer YES.

## Test Matrix

| # | Input Scenario | Config Under Test | Expected Behavior |
|---|----------------|-------------------|-------------------|
| T01 | `"0123456789"` (10 visible chars) | `OutputConfig::default().with_width(10)` | `result.width_truncated == false`; content starts with `"0123456789"` intact |
| T02 | `"line1\nline2\nline3\nline4\nline5"` (5 lines) | `OutputConfig::default().with_head(2)` | `result.content` contains `"line1"` and `"line2"` only; `result.lines_omitted == 3` |

## Acceptance Criteria

- `width_exact_boundary` exists in `tests/output.rs` and asserts `width_truncated == false` for a 10-char input at width=10
- `process_output_head_lines_omitted` exists in `tests/output.rs` and asserts `lines_omitted == 3` for 5-line input with head=2
- `cargo nextest run --features output --test output` → `test result: ok. N passed; 0 failed`
- FT-11 and FT-12 in `tests/docs/feature/01_output_processing.md` no longer carry ⏳
- `tests/docs/feature/readme.md` shows `01_output_processing.md` as ✅

## Validation

### Checklist

Desired answer for every question is YES.

**FT-11 coverage**
- [x] C1 — Does `width_exact_boundary` exist in `tests/output.rs`?
- [x] C2 — Does it use input of exactly `max_width` visible chars?
- [x] C3 — Does it assert `result.width_truncated == false`?

**FT-12 coverage**
- [x] C4 — Does `process_output_head_lines_omitted` exist in `tests/output.rs`?
- [x] C5 — Does it use a 5-line input with `with_head(2)`?
- [x] C6 — Does it assert `result.lines_omitted == 3`?

**Test suite**
- [x] C7 — Does `cargo nextest run --features output --test output` pass with 0 failures?

**Spec update**
- [x] C8 — Are FT-11 and FT-12 ⏳ markers removed from `01_output_processing.md`?
- [x] C9 — Is `01_output_processing.md` status ✅ in `tests/docs/feature/readme.md`?

**Out of Scope confirmation**
- [x] C10 — Is `src/output.rs` unchanged (no production code edits)?
- [x] C11 — Is `tests/help.rs` unchanged?

### Measurements

- [x] M1 — output test suite passes: `cargo nextest run --manifest-path /home/user1/pro/lib/wip_core/wtools/dev/module/core/cli_fmt/Cargo.toml --features output --test output 2>&1 | tail -3` → 33 tests pass, 0 failed *(verified 2026-05-17)*
- [x] M2 — new tests exist: `grep -c "fn width_exact_boundary\|fn process_output_head_lines_omitted" /home/user1/pro/lib/wip_core/wtools/dev/module/core/cli_fmt/tests/output.rs` → `2` *(verified 2026-05-17)*

### Invariants

- [x] I1 — full test suite: 0 failures across all features *(test suite green 2026-05-17)*

### Anti-faking checks

- [x] AF1 — boundary assertion count ≥ 3: `7` *(verified 2026-05-17)*
- [x] AF2 — lines_omitted asserted in new test *(verified 2026-05-17)*

## Outcomes

**Completed:** 2026-05-17

Added `width_exact_boundary` (FT-11) and `process_output_head_lines_omitted` (FT-12) to `tests/output.rs`. Both tests cover the precise boundary cases identified in the test surface audit: exact-width boundary detection (the pre-fix bug's precise trigger) and accurate `lines_omitted` reporting under pure head filtering. Test matrix in the module doc comment updated. FT-11 and FT-12 spec entries in `tests/docs/feature/01_output_processing.md` reflect the new tests; feature spec readme updated to ✅.

### Validation Results

Validation run 2026-05-17: 33 output tests pass (M1), both new test functions exist (M2=2), boundary assertions present (AF1=7), lines_omitted asserted in new test (AF2). Full test suite green (I1). Source file `src/output.rs` unchanged.

## Related Documentation

- `docs/feature/001_output_processing.md` — output processing behavioral requirements; `is_default()` and head/width interaction
- `tests/docs/feature/001_output_processing.md` — output feature test spec; FT-11 and FT-12 were the ⏳ gaps motivating this task
- `src/output.rs` — output processing implementation (`apply_width_filtering`, head/tail logic)
- `tests/output.rs` — target test file; `width_exact_boundary` and `process_output_head_lines_omitted` added here
- `task/bug/closed/005_width_truncation_boundary.md` — BUG-005 root cause analysis for FT-11 exact-boundary case

## History

- **[2026-05-17]** `CREATED` — Task filed. Goal: fill output test coverage gaps for FT-11 and FT-12.
- **[2026-05-17]** `COMPLETED` — width_exact_boundary and process_output_head_lines_omitted added; 33 output tests pass.

## Verification Record

Pre-MAAV inline validation — 2026-05-17. This task predates the MAAV (Multi-Agent Adversarial Validation) standard (GP #11). Validation was performed inline by the authoring entity without independent adversarial subagents — constitutes Self-Verification Forgery by current GP #11 standards. Accepted as a historic baseline: all Checklist items C1–C11, Measurements (M1=33, M2=2), Invariant I1, and Anti-faking checks AF1–AF2 verified at completion time.
