#2125 Report an error when source parameter could not be determined from target mapping

processor/src/main/java/org/mapstruct/ap/internal/model/BeanMappingMethod.java

@@ -65,6 +65,8 @@ import static org.mapstruct.ap.internal.util.Message.BEANMAPPING_NOT_ASSIGNABLE;
 import static org.mapstruct.ap.internal.util.Message.GENERAL_ABSTRACT_RETURN_TYPE;
 import static org.mapstruct.ap.internal.util.Message.GENERAL_AMBIGUOUS_CONSTRUCTORS;
 import static org.mapstruct.ap.internal.util.Message.GENERAL_CONSTRUCTOR_PROPERTIES_NOT_MATCHING_PARAMETERS;
+import static org.mapstruct.ap.internal.util.Message.PROPERTYMAPPING_CANNOT_DETERMINE_SOURCE_PARAMETER_FROM_TARGET;
+import static org.mapstruct.ap.internal.util.Message.PROPERTYMAPPING_CANNOT_DETERMINE_SOURCE_PROPERTY_FROM_TARGET;
 
 /**
  * A {@link MappingMethod} implemented by a {@link Mapper} class which maps one bean type to another, optionally
@@ -1113,6 +1115,31 @@ public class BeanMappingMethod extends NormalTypeMappingMethod {
                         errorOccured = true;
                     }
                 }
+                else {
+                    errorOccured = true;
+
+                    if ( method.getSourceParameters().size() == 1 ) {
+                        ctx.getMessager()
+                            .printMessage(
+                                method.getExecutable(),
+                                mapping.getMirror(),
+                                mapping.getTargetAnnotationValue(),
+                                PROPERTYMAPPING_CANNOT_DETERMINE_SOURCE_PROPERTY_FROM_TARGET,
+                                method.getSourceParameters().get( 0 ).getName(),
+                                targetPropertyName
+                            );
+                    }
+                    else {
+                        ctx.getMessager()
+                            .printMessage(
+                                method.getExecutable(),
+                                mapping.getMirror(),
+                                mapping.getTargetAnnotationValue(),
+                                PROPERTYMAPPING_CANNOT_DETERMINE_SOURCE_PARAMETER_FROM_TARGET,
+                                targetPropertyName
+                            );
+                    }
+                }
             }
             // remaining are the mappings without a 'source' so, 'only' a date format or qualifiers
             if ( propertyMapping != null ) {

processor/src/main/java/org/mapstruct/ap/internal/util/Message.java

@@ -73,6 +73,8 @@ public enum Message {
     PROPERTYMAPPING_NO_READ_ACCESSOR_FOR_TARGET_TYPE( "No read accessor found for property \"%s\" in target type." ),
     PROPERTYMAPPING_NO_WRITE_ACCESSOR_FOR_TARGET_TYPE( "No write accessor found for property \"%s\" in target type." ),
     PROPERTYMAPPING_WHITESPACE_TRIMMED( "The property named \"%s\" has whitespaces, using trimmed property \"%s\" instead.", Diagnostic.Kind.WARNING ),
+    PROPERTYMAPPING_CANNOT_DETERMINE_SOURCE_PROPERTY_FROM_TARGET("The type of parameter \"%s\" has no property named \"%s\". Please define the source property explicitly."),
+    PROPERTYMAPPING_CANNOT_DETERMINE_SOURCE_PARAMETER_FROM_TARGET("No property named \"%s\" exists in source parameter(s). Please define the source explicitly."),
 
     CONVERSION_LOSSY_WARNING( "%s has a possibly lossy conversion from %s to %s.", Diagnostic.Kind.WARNING ),
     CONVERSION_LOSSY_ERROR( "Can't map %s. It has a possibly lossy conversion from %s to %s." ),

processor/src/test/java/org/mapstruct/ap/test/bugs/_2077/Issue2077ErroneousMapper.java

@@ -8,7 +8,6 @@ package org.mapstruct.ap.test.bugs._2077;
 import org.mapstruct.Mapper;
 import org.mapstruct.Mapping;
 import org.mapstruct.ReportingPolicy;
-import org.mapstruct.factory.Mappers;
 
 /**
  * @author Sjaak Derksen
@@ -16,8 +15,6 @@ import org.mapstruct.factory.Mappers;
 @Mapper( unmappedTargetPolicy = ReportingPolicy.ERROR )
 public interface Issue2077ErroneousMapper {
 
-    Issue2077ErroneousMapper INSTANCE = Mappers.getMapper( Issue2077ErroneousMapper.class );
-
     @Mapping(target = "s1", defaultValue = "xyz" )
     Target map(String source);
 

processor/src/test/java/org/mapstruct/ap/test/bugs/_2077/Issue2077Test.java

@@ -30,8 +30,9 @@ public class Issue2077Test {
         diagnostics = {
             @Diagnostic(type = Issue2077ErroneousMapper.class,
                 kind = ERROR,
-                line = 22,
+                line = 18,
-                message = "Unmapped target property: \"s1\".")
+                message = "The type of parameter \"source\" has no property named \"s1\". Please define the source " +
+                    "property explicitly.")
         }
     )
     public void shouldNotCompile() {

processor/src/test/java/org/mapstruct/ap/test/bugs/_2125/Comment.java

@@ -0,0 +1,27 @@
+/*
+ * 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._2125;
+
+/**
+ * @author Filip Hrisafov
+ */
+public class Comment {
+    private final Integer issueId;
+    private final String comment;
+
+    public Comment(Integer issueId, String comment) {
+        this.issueId = issueId;
+        this.comment = comment;
+    }
+
+    public Integer getIssueId() {
+        return issueId;
+    }
+
+    public String getComment() {
+        return comment;
+    }
+}

processor/src/test/java/org/mapstruct/ap/test/bugs/_2125/Issue2125ErroneousMapper.java

@@ -0,0 +1,28 @@
+/*
+ * 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._2125;
+
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+import org.mapstruct.Named;
+
+@Mapper
+public interface Issue2125ErroneousMapper {
+
+    @Mapping(target = "issueId", qualifiedByName = "mapIssueNumber")
+    @Mapping( target = "comment", ignore = true)
+    Comment clone(Repository repository);
+
+    @Mapping(target = "issueId", qualifiedByName = "mapIssueNumber")
+    @Mapping( target = "comment", ignore = true)
+    Comment clone(Comment comment, Repository repository);
+
+    @Named("mapIssueNumber")
+    default Integer mapIssueNumber(Integer issueNumber) {
+        return issueNumber != null ? issueNumber + 1 : null;
+    }
+
+}

processor/src/test/java/org/mapstruct/ap/test/bugs/_2125/Issue2125Mapper.java

@@ -0,0 +1,28 @@
+/*
+ * 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._2125;
+
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+import org.mapstruct.Named;
+import org.mapstruct.factory.Mappers;
+
+@Mapper
+public interface Issue2125Mapper {
+
+    Issue2125Mapper INSTANCE = Mappers.getMapper( Issue2125Mapper.class );
+
+    Comment clone(Comment comment, Integer issueId);
+
+    @Mapping(target = "issueId", qualifiedByName = "mapIssueNumber")
+    Comment cloneWithQualifier(Comment comment, Integer issueId);
+
+    @Named("mapIssueNumber")
+    default Integer mapIssueNumber(Integer issueNumber) {
+        return issueNumber != null ? issueNumber + 1 : null;
+    }
+
+}

processor/src/test/java/org/mapstruct/ap/test/bugs/_2125/Issue2125Test.java

@@ -0,0 +1,71 @@
+/*
+ * 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._2125;
+
+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;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@IssueKey("2125")
+@WithClasses({
+    Comment.class,
+    Repository.class,
+})
+@RunWith(AnnotationProcessorTestRunner.class)
+public class Issue2125Test {
+
+    @Test
+    @WithClasses({
+        Issue2125Mapper.class
+    })
+    public void shouldSelectProperMethod() {
+
+        Comment comment = Issue2125Mapper.INSTANCE.clone(
+            new Comment( 2125, "Fix issue" ),
+            1000
+        );
+
+        assertThat( comment ).isNotNull();
+        assertThat( comment.getIssueId() ).isEqualTo( 2125 );
+
+        comment = Issue2125Mapper.INSTANCE.cloneWithQualifier(
+            new Comment( 2125, "Fix issue" ),
+            1000
+        );
+
+        assertThat( comment ).isNotNull();
+        assertThat( comment.getIssueId() ).isEqualTo( 1001 );
+    }
+
+    @Test
+    @WithClasses({
+        Issue2125ErroneousMapper.class
+    })
+    @ExpectedCompilationOutcome(value = CompilationResult.FAILED,
+        diagnostics = {
+            @Diagnostic(type = Issue2125ErroneousMapper.class,
+                kind = javax.tools.Diagnostic.Kind.ERROR,
+                line = 15,
+                alternativeLine = 17, // For some reason javac reports the error on the method instead of the annotation
+                message = "The type of parameter \"repository\" has no property named \"issueId\". Please define the " +
+                    "source property explicitly."),
+            @Diagnostic(type = Issue2125ErroneousMapper.class,
+                kind = javax.tools.Diagnostic.Kind.ERROR,
+                line = 19,
+                alternativeLine = 21, // For some reason javac reports the error on the method instead of the annotation
+                message = "No property named \"issueId\" exists in source parameter(s). Please define the source " +
+                    "explicitly.")
+        })
+    public void shouldReportErrorWhenMultipleSourcesMatch() {
+    }
+}

processor/src/test/java/org/mapstruct/ap/test/bugs/_2125/Repository.java

@@ -0,0 +1,28 @@
+/*
+ * 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._2125;
+
+/**
+ * @author Filip Hrisafov
+ */
+public class Repository {
+
+    private final String owner;
+    private final String name;
+
+    public Repository(String owner, String name) {
+        this.owner = owner;
+        this.name = name;
+    }
+
+    public String getOwner() {
+        return owner;
+    }
+
+    public String getName() {
+        return name;
+    }
+}