Demote opentest4j between assumption exception classes (fixes #1985)

New order of priority:
* org.testng.SkipException
* org.junit.AssumptionViolatedException
* org.opentest4j.TestAbortedException

Author: scordio

src/main/java/org/assertj/core/api/Assumptions.java

@@ -1295,16 +1295,16 @@ protected static <ASSERTION> Class<? extends ASSERTION> generateAssumptionClass(
   }
 
   private static RuntimeException assumptionNotMet(AssertionError assertionError) throws ReflectiveOperationException {
-    Class<?> assumptionClass = getAssumptionClass("org.opentest4j.TestAbortedException");
+    Class<?> assumptionClass = getAssumptionClass("org.testng.SkipException");
     if (assumptionClass != null) return assumptionNotMet(assumptionClass, assertionError);
 
-    assumptionClass = getAssumptionClass("org.testng.SkipException");
+    assumptionClass = getAssumptionClass("org.junit.AssumptionViolatedException");
     if (assumptionClass != null) return assumptionNotMet(assumptionClass, assertionError);
 
-    assumptionClass = getAssumptionClass("org.junit.AssumptionViolatedException");
+    assumptionClass = getAssumptionClass("org.opentest4j.TestAbortedException");
     if (assumptionClass != null) return assumptionNotMet(assumptionClass, assertionError);
 
-    throw new IllegalStateException("Assumptions require opentest4j, TestNG or JUnit on the classpath");
+    throw new IllegalStateException("Assumptions require TestNG, JUnit or opentest4j on the classpath");
   }
 
   private static Class<?> getAssumptionClass(String className) {

src/test/java/org/assertj/core/util/AssertionsUtil.java

@@ -24,7 +24,7 @@
 
 import org.assertj.core.api.ThrowableAssert.ThrowingCallable;
 import org.assertj.core.api.ThrowableAssertAlternative;
-import org.opentest4j.TestAbortedException;
+import org.junit.AssumptionViolatedException;
 
 public class AssertionsUtil {
 
@@ -41,7 +41,7 @@ public static ThrowableAssertAlternative<AssertionError> assertThatAssertionErro
   }
 
   public static void expectAssumptionNotMetException(ThrowingCallable shouldRaiseError) {
-    assertThatThrownBy(shouldRaiseError).isInstanceOf(TestAbortedException.class);
+    assertThatThrownBy(shouldRaiseError).isInstanceOf(AssumptionViolatedException.class);
   }
 
   public static Charset getDifferentCharsetFrom(Charset charset) {