Name: testland/mockclock-jvm
Rating: 73.6 (1 reviews)
Author: testland

testland/mockclock-jvm

Wraps Java's java.time.Clock + InstantSource dependency-injection pattern for testing time-sensitive code. Covers Clock.fixed(instant, zone), Clock.offset(baseClock, duration), Clock.systemDefaultZone() for production, the InstantSource interface (Java 17+), and the recommended dependency-injection pattern (constructor-inject Clock instead of calling Instant.now() directly). Use when you need to wire the clock-injection pattern (Clock.fixed, Clock.offset, MutableClock, InstantSource, Spring @Bean) into JVM (Java / Kotlin / Scala) production or test code. For pure DST transition reference (skipped or repeated hours, IANA DB, cron-double-fire bug classes) without a clock-injection need, use dst-transition-reference instead.

Quality

92%

Does it follow best practices?

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Securityby

Passed

No findings from the security scan

Quality

Content

80%

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

A strong, executable reference for the JVM clock-injection pattern with good conciseness and actionability. It is weakest on workflow clarity (the DST example is hand-wavy and lacks validation) and on progressive disclosure (everything lives inline in one long file).

Suggestions

Make the DST test example concrete by replacing 'assert the behaviour matches docs' with an actual assertion showing the expected ZonedDateTime resolution, or move it entirely into dst-transition-reference.

Split the advanced techniques (MutableClock, InstantSource, Spring DI) into reference files under references/ and keep SKILL.md as a tighter overview with one-level-deep pointers, improving progressive disclosure.

Add a brief validation step to the Running section (e.g. expected test count or a sanity assertion) so the production→test workflow has an explicit checkpoint.

Dimension	Reasoning	Score
Conciseness	Lean and code-dominated; the only prose is a short overview with a doc citation anchoring the recommended DI pattern, and minimal one-line notes per technique — no padding with concepts Claude already knows.	3 / 3
Actionability	Complete, copy-paste-ready Java for each technique (injection, Clock.fixed, Clock.offset, MutableClock, InstantSource, Spring DI), plus runnable 'mvn test / gradle test' and a CI YAML — fully executable rather than pseudocode.	3 / 3
Workflow Clarity	The core production-inject→test-fixed pattern is clear, but the DST test section is vague ('assert the behaviour matches docs' with no concrete assertion) and there are no validation checkpoints; the body is a catalog of parallel techniques rather than a sequenced workflow.	2 / 3
Progressive Disclosure	Sections are well-organized and the References section cleanly signals one-level-deep companion skills and external docs, but the ~220-line body keeps every advanced sub-technique inline with no bundle files offloading detail.	2 / 3
	Total	10 / 12 Passed

Description

100%

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A precise, trigger-rich description that states concrete capabilities, gives explicit use-when guidance, and actively disambiguates from a sibling skill. It is long but every clause carries load.

Dimension	Reasoning	Score
Specificity	Lists multiple concrete actions — 'Clock.fixed(instant, zone), Clock.offset(baseClock, duration), Clock.systemDefaultZone() ... InstantSource interface (Java 17+), and the recommended dependency-injection pattern (constructor-inject Clock)' — rather than vague language.	3 / 3
Completeness	Explicitly answers both what ('Wraps ... dependency-injection pattern for testing time-sensitive code') and when ('Use when you need to wire the clock-injection pattern ... into JVM ... production or test code').	3 / 3
Trigger Term Quality	Uses natural terms a JVM developer would say when needing this skill: 'Clock.fixed', 'Clock.offset', 'MutableClock', 'InstantSource', 'Spring @Bean', and 'Instant.now()', with good coverage across Java/Kotlin/Scala.	3 / 3
Distinctiveness Conflict Risk	Clear JVM-clock-injection niche with an explicit redirect — 'For pure DST transition reference ... without a clock-injection need, use dst-transition-reference instead' — making conflicts unlikely.	3 / 3
	Total	12 / 12 Passed

Validation

100%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Reviewed

5 days ago

Table of Contents

Discovery Implementation Validation