lock.lock();

    boolean satisfied = false;
    try {
      return satisfied = guard.isSatisfied();
    } finally {
      if (!satisfied) {
        lock.unlock();
      }
    }
  }

  /**
   * Enters this monitor if the guard is satisfied. Blocks at most the given time acquiring the
   * lock, but does not wait for the guard to be satisfied.
   *

    /**
     * Returns true if the precondition is satisfied.
     * @throws Exception if the precondition cannot be checked
     */
    boolean isSatisfied() throws Exception;

    /**
     * Utility method to check if a precondition class is satisfied.
     *
     * @param preconditionClass the class of the precondition to be checked
     * @return true if the precondition is satisfied

    lock.lock();

    boolean satisfied = false;
    try {
      return satisfied = guard.isSatisfied();
    } finally {
      if (!satisfied) {
        lock.unlock();
      }
    }
  }

  /**
   * Enters this monitor if the guard is satisfied. Blocks at most the given time acquiring the
   * lock, but does not wait for the guard to be satisfied.
   *

            "java.sourceCompatibility = 1.8"
        } else if (versionNumber < VersionNumber.parse('6.4.0') && TestPrecondition.satisfied(UnitTestPreconditions.Jdk10OrLater)) {
            "java.sourceCompatibility = 9"
        } else if (versionNumber < VersionNumber.parse('6.6.0') && TestPrecondition.satisfied(UnitTestPreconditions.Jdk11OrLater)) {

import static org.gradle.test.precondition.TestPrecondition.satisfied;
import static org.gradle.test.precondition.TestPrecondition.notSatisfied;

@CompileStatic
class UnitTestPreconditions {

    static final class Symlinks implements TestPrecondition {
        @Override
        boolean isSatisfied() {
            return satisfied(MacOs) || satisfied(Linux)
        }
    }

    private volatile boolean satisfied;

    public TestGuard(boolean satisfied) {
      super(MonitorTestCase.this.monitor);
      this.satisfied = satisfied;
    }

    @Override
    public boolean isSatisfied() {
      return this.satisfied;
    }

    public void setSatisfied(boolean satisfied) {
      this.satisfied = satisfied;
    }
  }

  private final boolean interruptible;

        @Override
        boolean isSatisfied() throws Exception {
            return satisfied(UnitTestPreconditions.UnixDerivative) && locate("bash") != null
        }
    }

    static class DashAvailable implements TestPrecondition {
        @Override
        boolean isSatisfied() throws Exception {
            return satisfied(UnitTestPreconditions.UnixDerivative) && locate("dash") != null
        }
    }

    private volatile boolean satisfied;

    public TestGuard(boolean satisfied) {
      super(MonitorTestCase.this.monitor);
      this.satisfied = satisfied;
    }

    @Override
    public boolean isSatisfied() {
      return this.satisfied;
    }

    public void setSatisfied(boolean satisfied) {
      this.satisfied = satisfied;
    }
  }

  private final boolean interruptible;

# Gradle / precondition Tester

This project collections information about where test preconditions can be satisfied.
We can use this information (i.e. by looking at the test results in Develocity) to see if we have any preconditions or combinations of preconditions, which are never satisfied – a situation which we otherwise would hardly notice.

 * <p>
 * Each combination can have three outcomes:
 * <ul>
 *     <li><b>Successful:</b> the precondition combination could be satisfied.</li>
 *     <li>
 *         <b>Skipped:</b> the precondition combination could <i>not</i> be satisfied.
 *         This is normal, and simply signifies that the precondition is not satisfied on the current system
 *     </li>
 *     <li>
 *         <b>Failed:</b> there was an error while checking the combination.