Fix logic errors in sys prop & env var @enabled conditions

Issue: #219

Author: sbrannen

junit-jupiter-api/src/main/java/org/junit/jupiter/api/condition/EnabledIfEnvironmentVariable.java

@@ -30,9 +30,8 @@
  * <p>When declared at the class level, the result will apply to all test methods
  * within that class as well.
  *
- * <p>If the specified environment variable is undefined, the presence of this
- * annotation will have no effect on whether or not the class or method
- * is enabled.
+ * <p>If the specified environment variable is undefined, the annotated class or
+ * method will be disabled.
  *
  * @since 5.1
  * @see DisabledIfEnvironmentVariable

junit-jupiter-api/src/main/java/org/junit/jupiter/api/condition/EnabledIfEnvironmentVariableCondition.java

@@ -51,14 +51,12 @@ public ConditionEvaluationResult evaluateExecutionCondition(ExtensionContext con
 
 		// Nothing to match against?
 		if (actual == null) {
-			return enabled(format("Environment variable [%s] does not exist", name));
+			return disabled(format("Environment variable [%s] does not exist", name));
 		}
-
 		if (actual.matches(regex)) {
 			return enabled(format("Environment variable [%s] with value [%s] matches regular expression [%s]", name,
 				actual, regex));
 		}
-		// else
 		return disabled(format("Environment variable [%s] with value [%s] does not match regular expression [%s]", name,
 			actual, regex));
 	}

junit-jupiter-api/src/main/java/org/junit/jupiter/api/condition/EnabledIfSystemProperty.java

@@ -30,9 +30,8 @@
  * <p>When declared at the class level, the result will apply to all test methods
  * within that class as well.
  *
- * <p>If the specified system property is undefined, the presence of this
- * annotation will have no effect on whether or not the class or method
- * is enabled.
+ * <p>If the specified system property is undefined, the annotated class or
+ * method will be disabled.
  *
  * @since 5.1
  * @see DisabledIfSystemProperty

junit-jupiter-api/src/main/java/org/junit/jupiter/api/condition/EnabledIfSystemPropertyCondition.java

@@ -51,14 +51,12 @@ public ConditionEvaluationResult evaluateExecutionCondition(ExtensionContext con
 
 		// Nothing to match against?
 		if (actual == null) {
-			return enabled(format("System property [%s] does not exist", name));
+			return disabled(format("System property [%s] does not exist", name));
 		}
-
 		if (actual.matches(regex)) {
 			return enabled(
 				format("System property [%s] with value [%s] matches regular expression [%s]", name, actual, regex));
 		}
-		// else
 		return disabled(
 			format("System property [%s] with value [%s] does not match regular expression [%s]", name, actual, regex));
 	}

junit-jupiter-engine/src/test/java/org/junit/jupiter/api/condition/EnabledIfEnvironmentVariableIntegrationTests.java

@@ -11,7 +11,6 @@
 package org.junit.jupiter.api.condition;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.junit.jupiter.api.Assertions.fail;
 
 import org.junit.jupiter.api.Disabled;
@@ -52,7 +51,7 @@ void environmentVariableDoesNotMatch() {
 	@Test
 	@EnabledIfEnvironmentVariable(named = BOGUS, matches = "doesn't matter")
 	void environmentVariableDoesNotExist() {
-		assertNull(System.getenv(BOGUS));
+		fail("should be disabled");
 	}
 
 }