Fail the build if --tests filter is applied and no tests execute during the entire build (this allows for an empty set of filtered tests at single project level).

build.gradle

@@ -29,6 +29,7 @@ apply from: file('gradle/defaults-java.gradle')
 apply from: file('gradle/testing/defaults-tests.gradle')
 apply from: file('gradle/testing/defaults-tests-solr.gradle')
 apply from: file('gradle/testing/randomization.gradle')
+apply from: file('gradle/testing/fail-on-no-tests.gradle')
 
 // Maven publishing.
 apply from: file('gradle/maven/defaults-maven.gradle')

gradle/testing/fail-on-no-tests.gradle

@@ -0,0 +1,41 @@
+// If we run the test task with a filter we want to fail if no test actually ran (everything was excluded).
+
+configure(allprojects) {
+  plugins.withType(JavaPlugin) {
+    test {
+      filter {
+        failOnNoMatchingTests = false
+      }
+    }
+  }
+}
+
+gradle.taskGraph.whenReady { graph ->
+  def args = gradle.startParameter.taskNames
+  def filters = args.findAll({ arg ->
+    return arg == /--tests/
+  })
+
+  // Only apply the check if we are actually filtering.
+  if (!filters.isEmpty()) {
+    def testTasks = graph.allTasks.findAll { task -> task instanceof Test }
+    // ... and there are some test tasks in the execution graph.
+    if (!testTasks.isEmpty()) {
+      def executedTests = 0
+
+      testTasks.each { task ->
+        task.afterSuite { desc, result ->
+          executedTests += result.testCount
+        }
+      }
+
+      // After the build is finished, check the test count.
+      gradle.buildFinished {
+        if (executedTests == 0) {
+          throw new GradleException("No tests found for the given filters?")
+        }
+      }
+    }
+  }
+}
+