#3565 Presence check methods should not be considered as valid mapping candidates

processor/src/main/java/org/mapstruct/ap/internal/processor/creation/MappingResolverImpl.java

@@ -470,6 +470,9 @@ public class MappingResolverImpl implements MappingResolver {
         }
 
         private boolean isCandidateForMapping(Method methodCandidate) {
+            if ( methodCandidate.isPresenceCheck() ) {
+                return false;
+            }
             return isCreateMethodForMapping( methodCandidate ) || isUpdateMethodForMapping( methodCandidate );
         }
 

processor/src/test/java/org/mapstruct/ap/test/bugs/_3565/Issue3565Mapper.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.ap.test.bugs._3565;
+
+import java.util.Optional;
+
+import org.mapstruct.Condition;
+import org.mapstruct.Mapper;
+import org.mapstruct.factory.Mappers;
+
+/**
+ * @author Filip Hrisafov
+ */
+@Mapper
+public interface Issue3565Mapper {
+
+    Issue3565Mapper INSTANCE = Mappers.getMapper( Issue3565Mapper.class );
+
+    default <T> T mapFromOptional(Optional<T> value) {
+        return value.orElse( (T) null );
+    }
+
+    @Condition
+    default boolean isOptionalPresent(Optional<?> value) {
+        return value.isPresent();
+    }
+
+    Target map(Source source);
+
+    class Source {
+
+        private final Boolean condition;
+
+        public Source(Boolean condition) {
+            this.condition = condition;
+        }
+
+        public Optional<Boolean> getCondition() {
+            return Optional.ofNullable( this.condition );
+        }
+    }
+
+    class Target {
+        private String condition;
+
+        public Optional<String> getCondition() {
+            return Optional.ofNullable( this.condition );
+        }
+
+        public void setCondition(String condition) {
+            this.condition = condition;
+        }
+    }
+}

processor/src/test/java/org/mapstruct/ap/test/bugs/_3565/Issue3565Test.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright MapStruct Authors.
+ *
+ * Licensed under the Apache License version 2.0, available at http://www.apache.org/licenses/LICENSE-2.0
+ */
+package org.mapstruct.ap.test.bugs._3565;
+
+import org.mapstruct.ap.testutil.IssueKey;
+import org.mapstruct.ap.testutil.ProcessorTest;
+import org.mapstruct.ap.testutil.WithClasses;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * @author Filip Hrisafov
+ */
+@WithClasses(Issue3565Mapper.class)
+@IssueKey("3565")
+class Issue3565Test {
+
+    @ProcessorTest
+    void shouldGenerateValidCode() {
+        Issue3565Mapper.Target target = Issue3565Mapper.INSTANCE.map( new Issue3565Mapper.Source( null ) );
+
+        assertThat( target ).isNotNull();
+        assertThat( target.getCondition() ).isEmpty();
+
+        target = Issue3565Mapper.INSTANCE.map( new Issue3565Mapper.Source( false ) );
+
+        assertThat( target ).isNotNull();
+        assertThat( target.getCondition() ).hasValue( "false" );
+    }
+}