mapstruct#1742 API and UnitTest

core/src/main/java/org/mapstruct/Builder.java

@@ -29,4 +29,12 @@
      * @return the method that needs to tbe invoked on the builder
      */
     String buildMethod() default "build";
+
+    /**
+     * Toggling builders on / off. Builders are sometimes used solely for unit testing (fluent testdata)
+     * MapStruct will need to use the regular getters /setters in that case.
+     *
+     * @return when true, no builder patterns will be applied
+     */
+    boolean noBuilder() default false;
 }

processor/src/test/java/org/mapstruct/ap/test/builder/off/SimpleMapper.java

@@ -0,0 +1,20 @@
+/*
+ * 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.builder.off;
+
+import org.mapstruct.BeanMapping;
+import org.mapstruct.Builder;
+import org.mapstruct.CollectionMappingStrategy;
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+
+@Mapper(collectionMappingStrategy = CollectionMappingStrategy.ADDER_PREFERRED)
+public interface SimpleMapper {
+
+    @BeanMapping( builder = @Builder( noBuilder = true ) )
+    @Mapping(target = "name", source = "fullName")
+    SimpleNotRealyImmutablePerson toNotRealyImmutable(SimpleMutablePerson source);
+}

processor/src/test/java/org/mapstruct/ap/test/builder/off/SimpleMutablePerson.java

@@ -0,0 +1,21 @@
+/*
+ * 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.builder.off;
+
+import java.util.List;
+
+public class SimpleMutablePerson {
+    private String fullName;
+
+    public String getFullName() {
+        return fullName;
+    }
+
+    public void setFullName(String fullName) {
+        this.fullName = fullName;
+    }
+
+}

processor/src/test/java/org/mapstruct/ap/test/builder/off/SimpleNotRealyImmutableBuilderTest.java

@@ -0,0 +1,42 @@
+/*
+ * 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.builder.off;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mapstruct.ap.testutil.IssueKey;
+import org.mapstruct.ap.testutil.WithClasses;
+import org.mapstruct.ap.testutil.runner.AnnotationProcessorTestRunner;
+import org.mapstruct.ap.testutil.runner.GeneratedSource;
+import org.mapstruct.factory.Mappers;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@IssueKey("1743")
+@WithClasses({
+    SimpleMutablePerson.class,
+    SimpleNotRealyImmutablePerson.class
+})
+@RunWith(AnnotationProcessorTestRunner.class)
+public class SimpleNotRealyImmutableBuilderTest {
+
+    @Rule
+    public final GeneratedSource generatedSource = new GeneratedSource();
+
+    @Test
+    @WithClasses({ SimpleMapper.class })
+    public void testSimpleImmutableBuilderHappyPath() {
+        SimpleMapper mapper = Mappers.getMapper( SimpleMapper.class );
+        SimpleMutablePerson source = new SimpleMutablePerson();
+        source.setFullName( "Bob" );
+
+        SimpleNotRealyImmutablePerson targetObject = mapper.toNotRealyImmutable( source );
+
+        assertThat( targetObject.getName() ).isEqualTo( "Bob" );
+
+    }
+}

processor/src/test/java/org/mapstruct/ap/test/builder/off/SimpleNotRealyImmutablePerson.java

@@ -0,0 +1,44 @@
+/*
+ * 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.builder.off;
+
+public class SimpleNotRealyImmutablePerson {
+
+    private String name;
+
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    public SimpleNotRealyImmutablePerson() {
+    }
+
+    SimpleNotRealyImmutablePerson(Builder builder) {
+        this.name = builder.name;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public static class Builder {
+
+        private String name;
+
+        public Builder name(String name) {
+            throw new IllegalStateException( "name should not be called on builder" );
+        }
+
+        public SimpleNotRealyImmutablePerson build() {
+            return new SimpleNotRealyImmutablePerson( this );
+        }
+
+    }
+}