From 259ec446e38a81fca41d19496b1ae8d1adca7cc6 Mon Sep 17 00:00:00 2001
From: Klaus Lehner <172195+klu2@users.noreply.github.com>
Date: Sun, 17 Jul 2022 10:50:43 +0200
Subject: [PATCH] only load tests if dependent classes are on the classpath
 (#3)

---
 .../cleancode/archunit/CleanCodeRuleSets.kt   | 16 +++++++++----
 .../cleancode/archunit/utils/ClassUtils.kt    | 21 +++++++++++++++++
 .../archunit/utils/ClassUtilsTest.kt          | 23 +++++++++++++++++++
 3 files changed, 55 insertions(+), 5 deletions(-)
 create mode 100644 src/test/kotlin/io/cloudflight/cleancode/archunit/utils/ClassUtilsTest.kt

diff --git a/src/main/kotlin/io/cloudflight/cleancode/archunit/CleanCodeRuleSets.kt b/src/main/kotlin/io/cloudflight/cleancode/archunit/CleanCodeRuleSets.kt
index 5c4b9e2..270456a 100644
--- a/src/main/kotlin/io/cloudflight/cleancode/archunit/CleanCodeRuleSets.kt
+++ b/src/main/kotlin/io/cloudflight/cleancode/archunit/CleanCodeRuleSets.kt
@@ -1,20 +1,26 @@
 package io.cloudflight.cleancode.archunit
 
 import com.tngtech.archunit.junit.ArchTest
-import com.tngtech.archunit.junit.ArchTests
-import io.cloudflight.cleancode.archunit.rules.jpa.JpaRuleSet
 import io.cloudflight.cleancode.archunit.rules.jdk.JdkRuleSet
+import io.cloudflight.cleancode.archunit.rules.jpa.JpaRuleSet
 import io.cloudflight.cleancode.archunit.rules.logging.LoggingRuleSet
+import io.cloudflight.cleancode.archunit.utils.ruleSetOf
 
 class CleanCodeRuleSets {
 
     @ArchTest
-    val jpa = ArchTests.`in`(JpaRuleSet::class.java)
+    val jpa = ruleSetOf(
+        JpaRuleSet::class.java,
+        requiredClasses = arrayOf(
+            "javax.persistence.Entity",
+            "javax.validation.constraints.NotNull"
+        )
+    )
 
     @ArchTest
-    val logging = ArchTests.`in`(LoggingRuleSet::class.java)
+    val logging = ruleSetOf(LoggingRuleSet::class.java)
 
     @ArchTest
-    val jdk = ArchTests.`in`(JdkRuleSet::class.java)
+    val jdk = ruleSetOf(JdkRuleSet::class.java)
 
 }
diff --git a/src/main/kotlin/io/cloudflight/cleancode/archunit/utils/ClassUtils.kt b/src/main/kotlin/io/cloudflight/cleancode/archunit/utils/ClassUtils.kt
index 9607dc3..9ae9173 100644
--- a/src/main/kotlin/io/cloudflight/cleancode/archunit/utils/ClassUtils.kt
+++ b/src/main/kotlin/io/cloudflight/cleancode/archunit/utils/ClassUtils.kt
@@ -1,10 +1,31 @@
 package io.cloudflight.cleancode.archunit.utils
 
+import com.tngtech.archunit.junit.ArchTests
+
 fun Class<*>.isKotlinClass(): Boolean {
     return this.declaredAnnotations.any {
         it.annotationClass == Metadata::class
     }
 }
 
+internal fun ruleSetOf(clazz: Class<*>, vararg requiredClasses: String): ArchTests {
+    return if (classesExistOnClasspath(*requiredClasses)) {
+        ArchTests.`in`(clazz)
+    } else {
+        ArchTests.`in`(Object::class.java)
+    }
+}
+
+internal fun classesExistOnClasspath(vararg classes: String): Boolean {
+    classes.forEach {
+        try {
+            Class.forName(it)
+        } catch (err: ClassNotFoundException) {
+            return false
+        }
+    }
+    return true
+}
+
 
 
diff --git a/src/test/kotlin/io/cloudflight/cleancode/archunit/utils/ClassUtilsTest.kt b/src/test/kotlin/io/cloudflight/cleancode/archunit/utils/ClassUtilsTest.kt
new file mode 100644
index 0000000..a41f262
--- /dev/null
+++ b/src/test/kotlin/io/cloudflight/cleancode/archunit/utils/ClassUtilsTest.kt
@@ -0,0 +1,23 @@
+package io.cloudflight.cleancode.archunit.utils
+
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.Test
+
+class ClassUtilsTest {
+
+    @Test
+    fun existOnClassPath() {
+        assertThat(classesExistOnClasspath("java.lang.Object")).isTrue
+    }
+
+    @Test
+    fun dontExistOnClassPath() {
+        assertThat(classesExistOnClasspath("io.cloudflight.Foo")).isFalse
+    }
+
+    @Test
+    fun dontExistOnClassPath2() {
+        assertThat(classesExistOnClasspath("java.lang.Object", "io.cloudflight.Foo")).isFalse
+    }
+
+}
\ No newline at end of file