From 0495cb7fa77271193cc4e0e774080256cb185b73 Mon Sep 17 00:00:00 2001
From: Filip Hrisafov <filip.hrisafov@gmail.com>
Date: Sun, 19 Jul 2020 15:26:48 +0200
Subject: [PATCH] #2149 Do not allow using BeanMapping(ignoreByDefault = true)
 in combination with Mapping(target = ".")

This fixes an ArrayIndexOutOfBoundsException when they were used together
---
 .../model/source/MappingMethodOptions.java    | 43 +++++++---
 .../processor/MapperCreationProcessor.java    |  2 +-
 .../mapstruct/ap/internal/util/Message.java   |  1 +
 .../test/bugs/_2149/Erroneous2149Mapper.java  | 84 +++++++++++++++++++
 .../ap/test/bugs/_2149/Issue2149Test.java     | 47 +++++++++++
 5 files changed, 166 insertions(+), 11 deletions(-)
 create mode 100644 processor/src/test/java/org/mapstruct/ap/test/bugs/_2149/Erroneous2149Mapper.java
 create mode 100644 processor/src/test/java/org/mapstruct/ap/test/bugs/_2149/Issue2149Test.java

diff --git a/processor/src/main/java/org/mapstruct/ap/internal/model/source/MappingMethodOptions.java b/processor/src/main/java/org/mapstruct/ap/internal/model/source/MappingMethodOptions.java
index e0007949a..b7fd7f00d 100644
--- a/processor/src/main/java/org/mapstruct/ap/internal/model/source/MappingMethodOptions.java
+++ b/processor/src/main/java/org/mapstruct/ap/internal/model/source/MappingMethodOptions.java
@@ -11,11 +11,12 @@ import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
-import java.util.stream.Collectors;
 
 import org.mapstruct.ap.internal.gem.CollectionMappingStrategyGem;
 import org.mapstruct.ap.internal.model.common.Type;
 import org.mapstruct.ap.internal.model.common.TypeFactory;
+import org.mapstruct.ap.internal.util.FormattingMessager;
+import org.mapstruct.ap.internal.util.Message;
 import org.mapstruct.ap.internal.util.accessor.Accessor;
 
 import static org.mapstruct.ap.internal.model.source.MappingOptions.getMappingTargetNamesBy;
@@ -250,7 +251,8 @@ public class MappingMethodOptions {
         return false;
     }
 
-    public void applyIgnoreAll(SourceMethod method, TypeFactory typeFactory ) {
+    public void applyIgnoreAll(SourceMethod method, TypeFactory typeFactory,
+                               FormattingMessager messager) {
         CollectionMappingStrategyGem cms = method.getOptions().getMapper().getCollectionMappingStrategy();
         Type writeType = method.getResultType();
         if ( !method.isUpdateMethod() ) {
@@ -262,15 +264,27 @@ public class MappingMethodOptions {
         Map<String, Accessor> writeAccessors = writeType.getPropertyWriteAccessors( cms );
 
 
-        Set<String> mappedPropertyNames = mappings.stream()
-                                                  .map( m -> getPropertyEntries( m )[0] )
-                                                  .collect( Collectors.toSet() );
-
-        for ( String targetPropertyName : writeAccessors.keySet() ) {
-            if ( !mappedPropertyNames.contains( targetPropertyName ) ) {
-                MappingOptions mapping = MappingOptions.forIgnore( targetPropertyName );
-                mappings.add( mapping );
+        for ( MappingOptions mapping : mappings ) {
+            String mappedTargetProperty = getFirstTargetPropertyName( mapping );
+            if ( !".".equals( mappedTargetProperty ) ) {
+                // Remove the mapped target property from the write accessors
+                writeAccessors.remove( mappedTargetProperty );
             }
+            else {
+                messager.printMessage(
+                    method.getExecutable(),
+                    getBeanMapping().getMirror(),
+                    Message.BEANMAPPING_IGNORE_BY_DEFAULT_WITH_MAPPING_TARGET_THIS
+                );
+                // Nothing more to do if this is reached
+                return;
+            }
+        }
+
+        // The writeAccessors now contains only the accessors that should be ignored
+        for ( String targetPropertyName : writeAccessors.keySet() ) {
+            MappingOptions mapping = MappingOptions.forIgnore( targetPropertyName );
+            mappings.add( mapping );
         }
     }
 
@@ -290,4 +304,13 @@ public class MappingMethodOptions {
         return mapping.getTargetName().split( "\\." );
     }
 
+    private String getFirstTargetPropertyName(MappingOptions mapping) {
+        String targetName = mapping.getTargetName();
+        if ( ".".equals( targetName ) ) {
+            return targetName;
+        }
+
+        return getPropertyEntries( mapping )[0];
+    }
+
 }
diff --git a/processor/src/main/java/org/mapstruct/ap/internal/processor/MapperCreationProcessor.java b/processor/src/main/java/org/mapstruct/ap/internal/processor/MapperCreationProcessor.java
index e480eaf7a..25f25c3c3 100644
--- a/processor/src/main/java/org/mapstruct/ap/internal/processor/MapperCreationProcessor.java
+++ b/processor/src/main/java/org/mapstruct/ap/internal/processor/MapperCreationProcessor.java
@@ -486,7 +486,7 @@ public class MapperCreationProcessor implements ModelElementProcessor<List<Sourc
 
         // @BeanMapping( ignoreByDefault = true )
         if ( mappingOptions.getBeanMapping() != null && mappingOptions.getBeanMapping().isignoreByDefault() ) {
-            mappingOptions.applyIgnoreAll( method, typeFactory );
+            mappingOptions.applyIgnoreAll( method, typeFactory, mappingContext.getMessager() );
         }
 
         mappingOptions.markAsFullyInitialized();
diff --git a/processor/src/main/java/org/mapstruct/ap/internal/util/Message.java b/processor/src/main/java/org/mapstruct/ap/internal/util/Message.java
index e2a476ec9..2005127fe 100644
--- a/processor/src/main/java/org/mapstruct/ap/internal/util/Message.java
+++ b/processor/src/main/java/org/mapstruct/ap/internal/util/Message.java
@@ -39,6 +39,7 @@ public enum Message {
     BEANMAPPING_UNMAPPED_SOURCES_ERROR( "Unmapped source %s." ),
     BEANMAPPING_CYCLE_BETWEEN_PROPERTIES( "Cycle(s) between properties given via dependsOn(): %s." ),
     BEANMAPPING_UNKNOWN_PROPERTY_IN_DEPENDS_ON( "\"%s\" is no property of the method return type." ),
+    BEANMAPPING_IGNORE_BY_DEFAULT_WITH_MAPPING_TARGET_THIS( "Using @BeanMapping( ignoreByDefault = true ) with @Mapping( target = \".\", ... ) is not allowed. You'll need to explicitly ignore the target properties that should be ignored instead." ),
 
     PROPERTYMAPPING_MAPPING_NOTE( "mapping property: %s to: %s.", Diagnostic.Kind.NOTE ),
     PROPERTYMAPPING_CREATE_NOTE( "creating property mapping: %s.", Diagnostic.Kind.NOTE ),
diff --git a/processor/src/test/java/org/mapstruct/ap/test/bugs/_2149/Erroneous2149Mapper.java b/processor/src/test/java/org/mapstruct/ap/test/bugs/_2149/Erroneous2149Mapper.java
new file mode 100644
index 000000000..2b8d73cec
--- /dev/null
+++ b/processor/src/test/java/org/mapstruct/ap/test/bugs/_2149/Erroneous2149Mapper.java
@@ -0,0 +1,84 @@
+/*
+ * 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._2149;
+
+import org.mapstruct.BeanMapping;
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+
+/**
+ * @author Filip Hrisafov
+ */
+@Mapper
+public interface Erroneous2149Mapper {
+
+    @BeanMapping(ignoreByDefault = true)
+    @Mapping(target = ".", source = "name")
+    Target map(Source source);
+
+    class Target {
+
+        private String firstName;
+        private String age;
+        private String address;
+
+        public String getFirstName() {
+            return firstName;
+        }
+
+        public void setFirstName(String firstName) {
+            this.firstName = firstName;
+        }
+
+        public String getAge() {
+            return age;
+        }
+
+        public void setAge(String age) {
+            this.age = age;
+        }
+
+        public String getAddress() {
+            return address;
+        }
+
+        public void setAddress(String address) {
+            this.address = address;
+        }
+    }
+
+    class Source {
+
+        private final String age;
+        private final Name name;
+
+        public Source(String age, Name name) {
+            this.age = age;
+            this.name = name;
+        }
+
+        public String getAge() {
+            return age;
+        }
+
+        public Name getName() {
+            return name;
+        }
+    }
+
+    class Name {
+
+        private final String firstName;
+
+        public Name(String firstName) {
+            this.firstName = firstName;
+        }
+
+        public String getFirstName() {
+            return firstName;
+        }
+    }
+}
diff --git a/processor/src/test/java/org/mapstruct/ap/test/bugs/_2149/Issue2149Test.java b/processor/src/test/java/org/mapstruct/ap/test/bugs/_2149/Issue2149Test.java
new file mode 100644
index 000000000..80cfbcc7d
--- /dev/null
+++ b/processor/src/test/java/org/mapstruct/ap/test/bugs/_2149/Issue2149Test.java
@@ -0,0 +1,47 @@
+/*
+ * 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._2149;
+
+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.compilation.annotation.CompilationResult;
+import org.mapstruct.ap.testutil.compilation.annotation.Diagnostic;
+import org.mapstruct.ap.testutil.compilation.annotation.ExpectedCompilationOutcome;
+import org.mapstruct.ap.testutil.runner.AnnotationProcessorTestRunner;
+
+/**
+ * @author Filip Hrisafov
+ */
+@IssueKey("2149")
+@RunWith(AnnotationProcessorTestRunner.class)
+@WithClasses({
+    Erroneous2149Mapper.class
+})
+public class Issue2149Test {
+
+    @Test
+    @ExpectedCompilationOutcome(value = CompilationResult.FAILED,
+        diagnostics = {
+            @Diagnostic(
+                type = Erroneous2149Mapper.class,
+                kind = javax.tools.Diagnostic.Kind.ERROR,
+                line = 18,
+                message = "Using @BeanMapping( ignoreByDefault = true ) with @Mapping( target = \".\", ... ) is not " +
+                    "allowed. You'll need to explicitly ignore the target properties that should be ignored instead."
+            ),
+            @Diagnostic(
+                type = Erroneous2149Mapper.class,
+                kind = javax.tools.Diagnostic.Kind.WARNING,
+                line = 20,
+                message = "Unmapped target property: \"address\"."
+            )
+        }
+    )
+    public void shouldGiveCompileErrorWhenBeanMappingIgnoreByDefaultIsCombinedWithMappingTargetThis() {
+    }
+}