jiminhsieh/scalac-scoverage-plugin

scalac-scoverage-plugin is a free tool that helps Scala developers see how much of their code is actually tested. It generates detailed reports showing which statements and branches (the different paths code can take, like if/else conditions) were executed during test runs, and which were skipped. When tests run, the tool watches which lines of code get triggered and which don't, then produces an HTML report that highlights covered code in green and uncovered code in red. What makes this approach different is its focus on statement coverage rather than line coverage. Because Scala lets you pack multiple statements onto a single line, traditional line-by-line metrics can be misleading. A single line might contain a branch, and if your test only exercises one path, you'd see 100% line coverage while actually missing half the logic. By counting individual statements, it gives a more accurate picture of what's genuinely tested. A team building a Scala application would use this to keep their test suite honest. For example, if you have an age-check function that returns different messages depending on the user's age, the tool shows whether your tests actually try every age bracket. If half the branches are never hit, you know your tests have gaps before you ship. This repository is the core engine, a plugin that hooks into the Scala compiler. In practice, you wouldn't use this directly, instead, you'd add it through build tools like sbt, Maven, or Gradle, which wire it into your project automatically. You can also exclude specific packages or mark sections of code with special comments to skip coverage measurement on things you don't want counted.