Configure japicc task to check source and binary compatibility

Author: marcphilipp

build.gradle

@@ -267,10 +267,33 @@ subprojects { subproj ->
 		if (subproj.name in platformProjects) {
 			subproj.group = platformGroup
 			subproj.version = platformVersion
+			subproj.baseline = platformBaseline
 		}
 		else if (subproj.name in vintageProjects) {
 			subproj.group = vintageGroup
 			subproj.version = vintageVersion
+			subproj.baseline = vintageBaseline
+		}
+
+		configurations {
+			base
+		}
+
+		dependencies {
+			base(group: subproj.group, name: subproj.name, version: subproj.baseline) {
+				force = true
+				transitive = false
+			}
+		}
+
+		task japicc(type: Exec, dependsOn: assemble) {
+			// Requires https://github.com/lvc/japi-compliance-checker to be installed
+			def reportPath = "$buildDir/reports/japicc-${subproj.name}.html"
+			inputs.file configurations.base[0]
+			inputs.file jar.archivePath
+			outputs.file reportPath
+			commandLine 'japi-compliance-checker', configurations.base[0], jar.archivePath, '-report-path', reportPath
+			ignoreExitValue = true
 		}
 
 		javadoc {

gradle.properties

@@ -1,11 +1,14 @@
 group               = org.junit.jupiter
 version             = 5.1.0-SNAPSHOT
+baseline            = 5.0.3
 
 platformGroup       = org.junit.platform
 platformVersion     = 1.1.0-SNAPSHOT
+platformBaseline    = 1.0.3
 
 vintageGroup        = org.junit.vintage
 vintageVersion      = 5.1.0-SNAPSHOT
+vintageBaseline     = 4.12.3
 
 # --release release
 # Compiles against the public, supported and documented API for a specific VM version.

junit-platform-console-standalone/junit-platform-console-standalone.gradle

@@ -40,6 +40,7 @@ javadoc {
 
 jar.enabled = false
 test.enabled = false // prevent supposed-to-fail integration tests from failing the build
+japicc.enabled = false
 
 shadowJar {
 	// Generate shadow jar only if the underlying manifest was regenerated.