#2880 Fix missing import for array mapping methods

Co-authored-by: Martin Kamp Jensen <martin.kamp.jensen@se.com>

processor/src/main/java/org/mapstruct/ap/internal/model/common/Type.java

@@ -181,8 +181,11 @@ public class Type extends ModelElement implements Comparable<Type> {
 
         this.loggingVerbose = loggingVerbose;
 
-        this.topLevelType = topLevelType( this.typeElement, this.typeFactory );
-        this.nameWithTopLevelTypeName = nameWithTopLevelTypeName( this.typeElement );
+        // The top level type for an array type is the top level type of the component type
+        TypeElement typeElementForTopLevel =
+            this.componentType == null ? this.typeElement : this.componentType.getTypeElement();
+        this.topLevelType = topLevelType( typeElementForTopLevel, this.typeFactory );
+        this.nameWithTopLevelTypeName = nameWithTopLevelTypeName( typeElementForTopLevel, this.name );
     }
     //CHECKSTYLE:ON
 
@@ -218,7 +221,17 @@ public class Type extends ModelElement implements Comparable<Type> {
      * (if the top level type is important, otherwise the fully-qualified name.
      */
     public String createReferenceName() {
-        if ( isToBeImported() || shouldUseSimpleName() ) {
+        if ( isToBeImported() ) {
+            // isToBeImported() returns true for arrays.
+            // Therefore, we need to check the top level type when creating the reference
+            if ( isTopLevelTypeToBeImported() ) {
+                return nameWithTopLevelTypeName != null ? nameWithTopLevelTypeName : name;
+            }
+
+            return name;
+        }
+
+        if ( shouldUseSimpleName() ) {
             return name;
         }
 
@@ -1566,16 +1579,16 @@ public class Type extends ModelElement implements Comparable<Type> {
         return trimmedClassName;
     }
 
-    private static String nameWithTopLevelTypeName(TypeElement element) {
+    private static String nameWithTopLevelTypeName(TypeElement element, String name) {
         if ( element == null ) {
             return null;
         }
         if ( !element.getNestingKind().isNested() ) {
-            return element.getSimpleName().toString();
+            return name;
         }
 
         Deque<CharSequence> elements = new ArrayDeque<>();
-        elements.addFirst( element.getSimpleName() );
+        elements.addFirst( name );
         Element parent = element.getEnclosingElement();
         while ( parent != null && parent.getKind() != ElementKind.PACKAGE ) {
             elements.addFirst( parent.getSimpleName() );

processor/src/test/java/org/mapstruct/ap/test/bugs/_2880/Issue2880Mapper.java

@@ -0,0 +1,14 @@
+/*
+ * 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._2880;
+
+import org.mapstruct.Mapper;
+
+@Mapper
+public interface Issue2880Mapper {
+
+    Target map(Source source);
+}

processor/src/test/java/org/mapstruct/ap/test/bugs/_2880/Issue2880Test.java

@@ -0,0 +1,25 @@
+/*
+ * 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._2880;
+
+import org.mapstruct.ap.testutil.IssueKey;
+import org.mapstruct.ap.testutil.ProcessorTest;
+import org.mapstruct.ap.testutil.WithClasses;
+
+@IssueKey("2880")
+@WithClasses({
+    Issue2880Mapper.class,
+    Outer.class,
+    Source.class,
+    Target.class,
+    TargetData.class
+})
+public class Issue2880Test {
+
+    @ProcessorTest
+    void shouldCompile() {
+    }
+}

processor/src/test/java/org/mapstruct/ap/test/bugs/_2880/Outer.java

@@ -0,0 +1,16 @@
+/*
+ * 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._2880;
+
+public class Outer {
+
+    public static class SourceData {
+
+        // CHECKSTYLE:OFF
+        public String value;
+        // CHECKSTYLE:ON
+    }
+}

processor/src/test/java/org/mapstruct/ap/test/bugs/_2880/Source.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.bugs._2880;
+
+import java.util.List;
+
+public class Source {
+
+    // CHECKSTYLE:OFF
+    public Outer.SourceData[] data1;
+
+    public Outer.SourceData[] data2;
+
+    public List<Outer.SourceData> data3;
+
+    public List<Outer.SourceData> data4;
+    // CHECKSTYLE:ON
+}

processor/src/test/java/org/mapstruct/ap/test/bugs/_2880/Target.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.bugs._2880;
+
+import java.util.List;
+
+public class Target {
+
+    // CHECKSTYLE:OFF
+    public TargetData[] data1;
+
+    public List<TargetData> data2;
+
+    public TargetData[] data3;
+
+    public List<TargetData> data4;
+    // CHECKSTYLE:ON
+}

processor/src/test/java/org/mapstruct/ap/test/bugs/_2880/TargetData.java

@@ -0,0 +1,13 @@
+/*
+ * 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._2880;
+
+public class TargetData {
+
+    // CHECKSTYLE:OFF
+    public String value;
+    // CHECKSTYLE:ON
+}