--- name: coverage-report description: > Run tests with code coverage collection, parse the results, and present a formatted coverage report — any language, discovery-driven. Dispatches by coverage_format from .claude/context/language-config.md. Supports cobertura, jacoco, lcov, json-summary, and go-cover. Highlights pass/fail against the configured threshold (default 90%). Read-only analysis. allowed-tools: Bash, Read, Grep, Glob argument-hint: "[repo-name-or-path]" --- # /coverage-report — Code Coverage Report (Language-Agnostic) **Usage:** `/coverage-report [repo-name-or-path]` Runs the repo's configured coverage command, locates the output file, dispatches parsing based on `coverage_format`, and produces a structured coverage report. No per-language logic lives in this skill — everything comes from discovered config. ## Pre-Flight: Resolve Target Repo 1. Read `.claude/context/language-config.md`. 2. Resolve the target repo via `$ARGUMENTS[0]` (repo name or path) or auto-detect from the current working directory. 3. From the matched entry, extract: - `project_root` - `coverage_command` - `coverage_format` — one of: `cobertura`, `jacoco`, `lcov`, `json-summary`, `go-cover`, `none` - `coverage_output_glob` - `coverage_threshold` (integer percentage; default 90 if missing) 4. **Early exit:** if `coverage_format == "none"`, print: ``` Coverage checks disabled for this repo (coverage_format: none). ``` and exit cleanly with no further action. ## Arguments - `$ARGUMENTS[0]` (optional): Repo name or path. If omitted, auto-detect. ## Steps ### 1. Run Tests with Coverage ```bash cd "" && 2>&1 ``` Capture the exit code. If the command fails, still proceed to locate and parse any coverage output that was produced, and flag the test failures in the report. ### 2. Locate Coverage File ```bash find "" -path "" -type f 2>/dev/null \ | sort -r | head -1 ``` Or, if `coverage_output_glob` is a plain glob (not a `find -path` expression): ```bash ls -t ""/ 2>/dev/null | head -1 ``` If no file is found, report the glob and instruct the user to re-check `coverage_output_glob` in `language-config.md`. Stop. ### 3. Parse Coverage Data (Format Dispatch) Dispatch on `coverage_format`. Each parser produces at minimum `line_pct` (float, 0–100). Some parsers also produce per-package / per-class breakdowns. Prefer shell tooling (`xmllint`, `grep`, `awk`) over inline Python when possible. Python is a **soft prerequisite** — fall back to Python only if `xmllint` is not available and the format requires XML parsing. #### Parser: `cobertura` Used by: dotnet (Coverlet), Python (coverage.py), Ruby (SimpleCov), PHP (PHPUnit). The root `` element carries `line-rate` as a float in `[0.0, 1.0]`. ```bash # Preferred: xmllint LINE_RATE=$(xmllint --xpath 'string(/coverage/@line-rate)' "") LINE_PCT=$(awk "BEGIN { printf \"%.1f\", ${LINE_RATE} * 100 }") # Fallback: grep LINE_RATE=$(grep -oE 'line-rate="[0-9.]+"' "" | head -1 \ | grep -oE '[0-9.]+') LINE_PCT=$(awk "BEGIN { printf \"%.1f\", ${LINE_RATE} * 100 }") ``` For per-package breakdown, iterate `` elements and read each `line-rate`. #### Parser: `jacoco` Used by: Java (Maven/Gradle with JaCoCo plugin). The root element (``) contains a direct-child ``. ```bash # Preferred: xmllint MISSED=$(xmllint --xpath 'string(/report/counter[@type="LINE"]/@missed)' "") COVERED=$(xmllint --xpath 'string(/report/counter[@type="LINE"]/@covered)' "") LINE_PCT=$(awk "BEGIN { t = ${MISSED} + ${COVERED}; if (t>0) printf \"%.1f\", ${COVERED}/t*100; else print \"0.0\" }") ``` Per-package: iterate `` elements and read each direct-child `` (skip nested counters inside classes/methods — take only the direct children). #### Parser: `lcov` Used by: JS/TS (Istanbul lcov reporter), Rust (tarpaulin), C/C++ (gcov/lcov). Parse `LF:N` (lines found) and `LH:N` (lines hit) lines. Sum across all records. ```bash TOTAL_LF=$(grep -E '^LF:' | awk -F: '{ sum += $2 } END { print sum+0 }') TOTAL_LH=$(grep -E '^LH:' | awk -F: '{ sum += $2 } END { print sum+0 }') LINE_PCT=$(awk "BEGIN { if (${TOTAL_LF}>0) printf \"%.1f\", ${TOTAL_LH}/${TOTAL_LF}*100; else print \"0.0\" }") ``` Per-file: each `SF:` record is followed by its own `LF`/`LH` — extract per-record for breakdown. #### Parser: `json-summary` Used by: Jest, Vitest, Istanbul (`--coverage-reporter=json-summary`). Read `total.lines.pct` from the JSON file. ```bash # Preferred: jq LINE_PCT=$(jq -r '.total.lines.pct' "") # Fallback: grep (brittle) LINE_PCT=$(grep -oE '"lines":\{[^}]*"pct":[0-9.]+' "" | head -1 \ | grep -oE '[0-9.]+$') ``` Per-file breakdown: iterate keys of the top-level object (skip `"total"`) and read `.lines.pct`. #### Parser: `go-cover` Used by: Go (`go test -coverprofile=`). The output file is a Go coverprofile. Run `go tool cover -func=` and extract the `total:` line's percentage: ```bash cd "" && go tool cover -func="" 2>&1 \ | awk '/^total:/ { gsub("%","",$NF); print $NF }' ``` Per-package breakdown: the same `go tool cover -func` output lists per-function coverage; aggregate by package (everything before the last `/`). #### Parser: unknown If `coverage_format` is anything other than the five above (and not `none`), fail loudly: ``` Unknown coverage format ''; supported formats: cobertura, jacoco, lcov, json-summary, go-cover. Update coverage_format in .claude/context/language-config.md or set coverage_format=none to skip coverage checks. ``` Stop — do not attempt generic parsing. ### 4. Compare Against Threshold ```bash THRESHOLD= # default 90 PASS=$(awk "BEGIN { print (${LINE_PCT} >= ${THRESHOLD}) ? \"PASS\" : \"FAIL\" }") ``` ### 5. Present Report ``` ╔══════════════════════════════════════════════════════════════╗ ║ CODE COVERAGE REPORT ║ ╚══════════════════════════════════════════════════════════════╝ Generated: Repo: Language: Format: Source: Test result: ─── Overall Coverage ────────────────────────────────────────── Line coverage: XX.X% %)> ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ [████████████░░░] XX.X% ─── Per-Package / Per-Module Breakdown ─────────────────────── 95.2% PASS 87.1% FAIL (below %) 91.4% PASS ─── Units Below Threshold ──────────────────────────────────── ─── Recommendations ─────────────────────────────────────────── % threshold."> ─────────────────────────────────────────────────────────────── ``` ### 6. Cleanup Do not delete coverage output files automatically — they live inside the repo's build output directory, and the user may want to inspect them. If a prior run left a known temporary directory (`./coverage-results` from dotnet/Coverlet defaults), the repo's own `.gitignore` should cover it. ## Threshold The default threshold is **90%** line coverage. The repo's `coverage_threshold` field overrides this. The report clearly marks whether the threshold is met. If below, list the top uncovered units to guide the Tester agent. ## Rules - This skill is **read-only analysis** — it does NOT modify source or test code. - Never hardcode language-specific logic (`dotnet`, `mvnw`, `jacoco`, `coverlet`, etc.). All commands and formats come from `language-config.md`. - If tests fail, report both the test failures AND the coverage data. - If coverage collection fails entirely, provide clear diagnostic steps pointing at `coverage_command`, `coverage_format`, and `coverage_output_glob` in the config. - Prefer shell + `xmllint`/`jq`/`awk` over inline Python. Python is a **soft prerequisite** — only fall back to it when the preferred tool is unavailable. - If `coverage_format == "none"`, exit cleanly with an informational message.