Some test artifacts should be build ahead of actually running the tests. These test artifacts compile source code into binaries, generate JAR files, install modules and package functions into zip files.
A build.sh script is availble as a convenience and will run ahead of tests when using gradle. However this script will not work on Windows as it currently assumes Bash is available.
Some artifacts are not build because they require additional tooling. Specifically, these are the unicode tests for the Ballerina and .NET runtimes. These unicode tests are checked however in their corresponding runtime build.
For Java artifacts, Java 8 is required. If not found in your path, the build script will skip those artifacts and corresponding tests will also be skipped.