migrate extra properties, buildScan and allprojects configuration to …

…Kotlin DSL (#123)

build.gradle.kts

@@ -14,4 +14,27 @@ plugins {
     id("com.github.kt3k.coveralls") version "2.9.0"
 }
 
+val isBuildOnJenkins by extra(System.getenv().getOrDefault("BUILD_TAG", "").startsWith("jenkins-"))
+println("buildOnJenkins = $isBuildOnJenkins for current build.")
+
+val skipSpotBugs by extra(hasProperty("skipSpotBugs"))
+println("Using skipSpotBugs = $skipSpotBugs for current build.")
+
+// set default junit versions if not set via command line
+val junit4Version by extra(findProperty("junit4Version")?.toString() ?: "4.12")
+println("Using JUnit4 version $junit4Version for current build.")
+val junitJupiterVersion by extra(findProperty("junitJupiterVersion")?.toString() ?: "5.5.2")
+println("Using JUnit Jupiter version $junitJupiterVersion for current build.")
+
+buildScan {
+    termsOfServiceUrl = "https://gradle.com/terms-of-service"
+    termsOfServiceAgree = "yes"
+}
+
+allprojects {
+    repositories {
+        mavenCentral()
+    }
+}
+
 apply(from = "legacy.build.gradle")

legacy.build.gradle

@@ -1,30 +1,3 @@
-ext {
-    isBuildOnJenkins = System.env["BUILD_TAG"]?.startsWith("jenkins-") ?: false
-    skipSpotBugs = hasProperty("skipSpotBugs")
-    println("Using skipSpotBugs = ${skipSpotBugs} for current build.")
-
-    if (!hasProperty("junit4Version")) { // set default junit version if not set via command line
-        junit4Version = "4.12"
-    }
-    println("Using JUnit4 version ${junit4Version} for current build.")
-
-    if (!hasProperty("junitJupiterVersion")) { // set default junit version if not set via command line
-        junitJupiterVersion = "5.5.2"
-    }
-    println("Using JUnit Jupiter version ${junitJupiterVersion} for current build.")
-}
-
-buildScan {
-    termsOfServiceUrl = "https://gradle.com/terms-of-service"
-    termsOfServiceAgree = "yes"
-}
-
-allprojects {
-    repositories {
-        mavenCentral()
-    }
-}
-
 subprojects {
     apply(plugin: "jacoco")
     apply(plugin: "java-library")