add-missing-unit-test

A workflow for adding a missing unit test or extending an existing test for a class, with Kover used to measure code coverage. Unit tests check small pieces of code in isolation; Kover reports how much code the tests exercise.

In plain words
What is it for?
Use it when a class lacks tests or an existing test file needs another case, including tests for edge cases and branches.
Why use it?
It helps identify untested logic, establish the current build and test state, and verify that the new tests improve coverage without breaking the project.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/flutter/flutter-intellij/add-missing-unit-test
Any agent
npx skills add flutter/flutter-intellij --skill add-missing-unit-test
Clone the repo
git clone --depth 1 https://github.com/flutter/flutter-intellij

Made for: Claude Code, Codex.

Per session 36 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 553 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00036 $0.00553
Opus 5 $0.00018 $0.00277
Sonnet 5 $0.00007 $0.00111
Haiku 4.5 $0.00004 $0.00055

Measured 3d ago against content hash fa5cfcba9629, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

add-missing-unit-test scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.agents/skills/add-missing-unit-test/SKILL.md · 42 lines

How it starts

The opening of the file, as written. The whole thing — 42 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Skill: Add Missing Unit Test

You are tasked with adding a new unit test for a class that currently lacks one, or adding a new test case to an existing test file, to improve code coverage and reliability.

Objective

Add a new unit test for a class that currently lacks one, or add a new test case to an existing test file, to improve code coverage and reliability.

Workflow Instructions

1. Identify Target

  • Choose a class in src/ that has complex logic but logic coverage is missing or incomplete.

2. Establish Baseline

  • Run ./gradlew testClasses to compile all sources (production and test) and ensure the project is in a valid state.
  • Run ./gradlew verifyPlugin to ensure no plugin verification issues exist.
  • Run ./gradlew test (or specific test if it exists) to establish current pass/fail status.
  • Run tests with Kover (./gradlew koverHtmlReport or ./gradlew koverXmlReport) to determine current coverage percentage for target class.

3. Implement Test

  • Create a new test class ([ClassName]Test) in testSrc/ if it doesn't exist.
  • Add test cases to cover specific methods, edge cases, and branches.
  • Ensure the test follows project testing conventions (naming, mocking, assertions).

4. Verify

  • Run ./gradlew testClasses to ensure new test compiles.
  • Run new test (and related tests) to ensure it passes.
  • Run ./gradlew verifyPlugin to ensure no regressions in plugin verification.
  • Run Kover again to confirm coverage improvement.

5. Report & Review

  • Summarize test added and coverage improvement.
  • Test Location: Explicitly state where in the IDE user should go to test changed functionality (e.g., "Run the new test file [TestFileName]").
  • Action: Ask user to review new test closely. Validate that code being tested is actively used (e.g., check that it is not dead code/0 references).
  • Do not commit or push.
  • Provide a suggested Git commit message, explicitly including the Kover coverage improvement:
    • Example Pattern: Add unit tests for [Class Name]. Coverage verified using Kover. Coverage improvement: [Class Name]: ~[X]% line coverage ([Y] covered, [Z] uncovered).

Read the full file on GitHub · 42 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 3d ago First seen · 42 lines · 36 tokens per session scan A fa5cfcba9629

Subscribe to this mod's changes

add-missing-unit-test is a skill published in the GitHub repository flutter/flutter-intellij (2,013 stars, last pushed 2d ago), licensed BSD-3-Clause. It adds 36 tokens to every session and 553 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.