Fix annotation style support for if(true) and if(false)

The documentation specifies annotation style pointcuts
can use if(false) or if(true) and not require a boolean
return value and body for the @Pointcut annotated
method but it doesn't work without this change to validation
that recognizes the situation.

Fixes #115

org.aspectj.ajdt.core/src/main/java/org/aspectj/ajdt/internal/compiler/ast/ValidateAtAspectJAnnotationsVisitor.java

@@ -528,6 +528,7 @@ public class ValidateAtAspectJAnnotationsVisitor extends ASTVisitor {
 
 		boolean noValueSupplied = true;
 		boolean containsIfPcd = false;
+		boolean isIfTrueOrFalse = false;
 		int[] pcLocation = new int[2];
 		String pointcutExpression = getStringLiteralFor("value", ajAnnotations.pointcutAnnotation, pcLocation);
 		try {
@@ -538,6 +539,11 @@ public class ValidateAtAspectJAnnotationsVisitor extends ASTVisitor {
 			} else {
 				noValueSupplied = false;
 				pc = new PatternParser(pointcutExpression, context).parsePointcut();
+				if (pc instanceof IfPointcut) {
+					if (((IfPointcut)pc).alwaysFalse() || ((IfPointcut)pc).alwaysTrue()) {
+						isIfTrueOrFalse = true;
+					}
+				}
 			}
 			pcDecl.pointcutDesignator = (pc == null) ? null : new PointcutDesignator(pc);
 			pcDecl.setGenerateSyntheticPointcutMethod();
@@ -592,10 +598,10 @@ public class ValidateAtAspectJAnnotationsVisitor extends ASTVisitor {
 					methodDeclaration.returnType.sourceEnd,
 					"Methods annotated with @Pointcut must return void unless the pointcut contains an if() expression");
 		}
-		if (!returnsBoolean && containsIfPcd) {
+		if (!returnsBoolean && containsIfPcd && !isIfTrueOrFalse) {
 			methodDeclaration.scope.problemReporter().signalError(methodDeclaration.returnType.sourceStart,
 					methodDeclaration.returnType.sourceEnd,
-					"Methods annotated with @Pointcut must return boolean when the pointcut contains an if() expression");
+					"Methods annotated with @Pointcut must return boolean when the pointcut contains an if() expression unless it is if(false) or if(true)");
 		}
 
 		if (methodDeclaration.statements != null && methodDeclaration.statements.length > 0 && !containsIfPcd) {

tests/bugs198/github_115/A.java

@@ -0,0 +1,32 @@
+import org.aspectj.lang.annotation.Aspect;
+import org.aspectj.lang.annotation.Before;
+import org.aspectj.lang.annotation.Pointcut;
+
+public class A {
+
+	public static void main(String []argv) {
+		System.out.println("A.main");
+	}
+
+}
+
+@Aspect
+class Azpect {
+	
+	@Pointcut("if(false)")
+	public void isFalse() { }
+
+	@Pointcut("if(true)")
+	public void isTrue() { }
+
+	@Before("isTrue() && execution(* A.main(..))")
+	public void beforeTrue() {
+		System.out.println("Azpect.beforeTrue");
+	}
+
+	@Before("isFalse() && execution(* A.main(..))")
+	public void beforeFalse() {
+		System.out.println("Azpect.beforeFalse");
+	}
+}
+

tests/bugs198/github_115/B.java

@@ -0,0 +1,33 @@
+import org.aspectj.lang.annotation.Aspect;
+import org.aspectj.lang.annotation.Before;
+import org.aspectj.lang.annotation.Pointcut;
+
+public class B {
+
+	public static void main(String []argv) {
+		System.out.println("B.main");
+	}
+
+}
+
+@Aspect
+abstract class AbstractAzpect {
+
+	@Pointcut
+	public abstract void isTrue();
+	
+	@Before("isTrue() && execution(* B.main(..))")
+	public void beforeFalse() {
+		System.out.println("Azpect.beforeFalse");
+	}
+}
+
+@Aspect
+class Azpect extends AbstractAzpect {
+	
+	@Override
+	@Pointcut("if(true)")
+	public void isTrue() { }
+
+}
+

tests/src/test/java/org/aspectj/systemtest/ajc198/Ajc198TestsJava.java

@@ -35,6 +35,14 @@ public class Ajc198TestsJava extends XMLBasedAjcTestCaseForJava17OrLater {
 		// TODO: replace 0 by Constants.PREVIEW_MINOR_VERSION after no longer using EA build, but final JDK version
 		checkVersion("PersonAspect", Constants.MAJOR_17, 0 /*Constants.PREVIEW_MINOR_VERSION*/);
 	}
+	
+	public void testAnnotationStyleSpecialIfClauses() {
+		runTest("annotation style A");
+	}
+
+	public void testAnnotationStylePointcutInheritanceWithIfClauses() {
+		runTest("annotation style B");
+	}
 
   public static Test suite() {
     return XMLBasedAjcTestCase.loadSuite(Ajc198TestsJava.class);

tests/src/test/resources/org/aspectj/systemtest/ajc198/ajc198.xml

@@ -100,4 +100,26 @@
 		<compile files="Buffers.java" options="--release 8"/>
 	</ajc-test>
 
+	<ajc-test dir="bugs198/github_115" title="annotation style A">
+		<compile files="A.java" options="-1.5">
+			<message kind="warning" line="28" text="advice defined in Azpect has not been applied [Xlint:adviceDidNotMatch]"/>
+		</compile>
+		<run class="A">
+			<stdout>
+				<line text="Azpect.before"/>
+				<line text="A.main"/>
+			</stdout>
+		</run>
+	</ajc-test>
+
+	<ajc-test dir="bugs198/github_115" title="annotation style B">
+		<compile files="B.java" options="-1.5"/>
+		<run class="B">
+			<stdout>
+				<line text="Azpect.before"/>
+				<line text="B.main"/>
+			</stdout>
+		</run>
+	</ajc-test>
+
 </suite>