#2135 improved messages for not able to select qualified method (#2141)

* #2135 improved messages for not able to select qualified method

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

@@ -10,8 +10,11 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 import java.util.function.Supplier;
+import java.util.stream.Collectors;
 import javax.lang.model.element.AnnotationMirror;
+import javax.lang.model.element.Element;
 import javax.lang.model.element.ExecutableElement;
+import javax.lang.model.element.Name;
 import javax.lang.model.element.TypeElement;
 import javax.lang.model.type.DeclaredType;
 import javax.lang.model.type.ExecutableType;
@@ -48,6 +51,7 @@ import org.mapstruct.ap.internal.model.source.selector.SelectionCriteria;
 import org.mapstruct.ap.internal.util.Collections;
 import org.mapstruct.ap.internal.util.FormattingMessager;
 import org.mapstruct.ap.internal.util.Message;
+import org.mapstruct.ap.internal.util.MessageConstants;
 import org.mapstruct.ap.internal.util.NativeTypes;
 import org.mapstruct.ap.internal.util.Strings;
 
@@ -260,13 +264,7 @@ public class MappingResolverImpl implements MappingResolver {
             }
 
             if ( hasQualfiers() ) {
-                messager.printMessage(
+                printQualifierMessage( selectionCriteria );
-                        mappingMethod.getExecutable(),
-                        positionHint,
-                        Message.GENERAL_NO_QUALIFYING_METHOD,
-                        Strings.join( selectionCriteria.getQualifiers(), ", " ),
-                        Strings.join( selectionCriteria.getQualifiedByNames(), ", " )
-                );
             }
             else if ( allowMappingMethod() ) {
                 // only forge if we would allow mapping method
@@ -281,6 +279,46 @@ public class MappingResolverImpl implements MappingResolver {
             return selectionCriteria != null && selectionCriteria.hasQualfiers();
         }
 
+        private void printQualifierMessage(SelectionCriteria selectionCriteria ) {
+
+            List<String> annotations = selectionCriteria.getQualifiers().stream()
+                .filter( DeclaredType.class::isInstance )
+                .map( DeclaredType.class::cast )
+                .map( DeclaredType::asElement )
+                .map( Element::getSimpleName )
+                .map( Name::toString )
+                .map( a -> "@" + a )
+                .collect( Collectors.toList() );
+            List<String> names = selectionCriteria.getQualifiedByNames();
+
+            if ( !annotations.isEmpty() && !names.isEmpty() ) {
+                messager.printMessage(
+                    mappingMethod.getExecutable(),
+                    positionHint,
+                    Message.GENERAL_NO_QUALIFYING_METHOD_COMBINED,
+                    Strings.join( names, MessageConstants.AND ),
+                    Strings.join( annotations, MessageConstants.AND )
+                );
+            }
+            else if ( !annotations.isEmpty() ) {
+                messager.printMessage(
+                    mappingMethod.getExecutable(),
+                    positionHint,
+                    Message.GENERAL_NO_QUALIFYING_METHOD_ANNOTATION,
+                    Strings.join( annotations, MessageConstants.AND )
+                );
+            }
+            else  {
+                messager.printMessage(
+                    mappingMethod.getExecutable(),
+                    positionHint,
+                    Message.GENERAL_NO_QUALIFYING_METHOD_NAMED,
+                    Strings.join( names, MessageConstants.AND )
+                );
+            }
+
+        }
+
         private boolean allowDirect( Type sourceType, Type targetType ) {
             if ( selectionCriteria != null && selectionCriteria.isAllowDirect() ) {
                 return true;

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

@@ -7,6 +7,8 @@ package org.mapstruct.ap.internal.util;
 
 import javax.tools.Diagnostic;
 
+import static org.mapstruct.ap.internal.util.MessageConstants.FAQ_QUALIFIER_URL;
+
 /**
  * A message used in warnings/errors raised by the annotation processor.
  *
@@ -119,7 +121,9 @@ public enum Message {
     GENERAL_JODA_NOT_ON_CLASSPATH( "Cannot validate Joda dateformat, no Joda on classpath. Consider adding Joda to the annotation processorpath.", Diagnostic.Kind.WARNING ),
     GENERAL_NOT_ALL_FORGED_CREATED( "Internal Error in creation of Forged Methods, it was expected all Forged Methods to finished with creation, but %s did not" ),
     GENERAL_NO_SUITABLE_CONSTRUCTOR( "%s does not have an accessible constructor." ),
-    GENERAL_NO_QUALIFYING_METHOD( "No qualifying method found for qualifiers: %s and / or qualifying names: %s" ),
+    GENERAL_NO_QUALIFYING_METHOD_ANNOTATION( "Qualifier error. No method found annotated with: [ %s ]. See " + FAQ_QUALIFIER_URL + " for more info." ),
+    GENERAL_NO_QUALIFYING_METHOD_NAMED( "Qualifier error. No method found annotated with @Named#value: [ %s ]. See " + FAQ_QUALIFIER_URL + " for more info." ),
+    GENERAL_NO_QUALIFYING_METHOD_COMBINED( "Qualifier error. No method found annotated with @Named#value: [ %s ], annotated with [ %s ]. See " + FAQ_QUALIFIER_URL + " for more info." ),
 
     BUILDER_MORE_THAN_ONE_BUILDER_CREATION_METHOD( "More than one builder creation method for \"%s\". Found methods: \"%s\". Builder will not be used. Consider implementing a custom BuilderProvider SPI.", Diagnostic.Kind.WARNING ),
     BUILDER_NO_BUILD_METHOD_FOUND("No build method \"%s\" found in \"%s\" for \"%s\". Found methods: \"%s\".", Diagnostic.Kind.ERROR ),
@@ -162,6 +166,7 @@ public enum Message {
     VALUEMAPPING_NON_EXISTING_CONSTANT( "Constant %s doesn't exist in enum type %s." );
     // CHECKSTYLE:ON
 
+
     private final String description;
     private final Diagnostic.Kind kind;
 

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

@@ -0,0 +1,15 @@
+/*
+ * 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.internal.util;
+
+public final class MessageConstants {
+
+    public static final String AND = " and ";
+    public static final String FAQ_QUALIFIER_URL = "https://mapstruct.org/faq/#qualifier";
+
+    private MessageConstants() {
+    }
+}

processor/src/test/java/org/mapstruct/ap/test/selection/qualifier/QualifierTest.java

@@ -103,8 +103,8 @@ public class QualifierTest {
                 kind = Kind.ERROR,
                 line = 28,
                 message =
-                    "No qualifying method found for qualifiers: org.mapstruct.ap.test.selection.qualifier.annotation" +
+                    "Qualifier error. No method found annotated with: [ @NonQualifierAnnotated ]. " +
-                        ".NonQualifierAnnotated and / or qualifying names: "),
+                        "See https://mapstruct.org/faq/#qualifier for more info."),
             @Diagnostic(
                 type = ErroneousMapper.class,
                 kind = Kind.ERROR,

processor/src/test/java/org/mapstruct/ap/test/selection/qualifier/errors/ErroneousMessageByAnnotationAndNamedMapper.java

@@ -0,0 +1,54 @@
+/*
+ * 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.selection.qualifier.errors;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+import org.mapstruct.Qualifier;
+
+@Mapper
+public interface ErroneousMessageByAnnotationAndNamedMapper {
+
+    @Mapping(target = "nested", source = "value", qualifiedBy = {
+        SelectMe1.class,
+        SelectMe2.class
+    }, qualifiedByName = { "selectMe1", "selectMe2" })
+    Target map(Source source);
+
+    default Nested map(String in) {
+        return null;
+    }
+
+    // CHECKSTYLE:OFF
+    class Source {
+        public String value;
+    }
+
+    class Target {
+        public Nested nested;
+    }
+
+    class Nested {
+        public String value;
+    }
+    // CHECKSTYLE ON
+
+    @Qualifier
+    @java.lang.annotation.Target(ElementType.METHOD)
+    @Retention(RetentionPolicy.CLASS)
+    public @interface SelectMe1 {
+    }
+
+    @Qualifier
+    @java.lang.annotation.Target(ElementType.METHOD)
+    @Retention(RetentionPolicy.CLASS)
+    public @interface SelectMe2 {
+    }
+}

processor/src/test/java/org/mapstruct/ap/test/selection/qualifier/errors/ErroneousMessageByAnnotationMapper.java

@@ -0,0 +1,45 @@
+/*
+ * 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.selection.qualifier.errors;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+import org.mapstruct.Qualifier;
+
+@Mapper
+public interface ErroneousMessageByAnnotationMapper {
+
+    @Mapping(target = "nested", source = "value", qualifiedBy = SelectMe.class)
+    Target map(Source source);
+
+    default Nested map(String in) {
+        return null;
+    }
+
+    // CHECKSTYLE:OFF
+    class Source {
+        public String value;
+    }
+
+    class Target {
+        public Nested nested;
+    }
+
+    class Nested {
+        public String value;
+    }
+    // CHECKSTYLE ON
+
+    @Qualifier
+    @java.lang.annotation.Target(ElementType.METHOD)
+    @Retention(RetentionPolicy.CLASS)
+    public @interface SelectMe {
+    }
+}

processor/src/test/java/org/mapstruct/ap/test/selection/qualifier/errors/ErroneousMessageByNamedMapper.java

@@ -0,0 +1,45 @@
+/*
+ * 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.selection.qualifier.errors;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+import org.mapstruct.Qualifier;
+
+@Mapper
+public interface ErroneousMessageByNamedMapper {
+
+    @Mapping(target = "nested", source = "value", qualifiedByName = "SelectMe")
+    Target map(Source source);
+
+    default Nested map(String in) {
+        return null;
+    }
+
+    // CHECKSTYLE:OFF
+    class Source {
+        public String value;
+    }
+
+    class Target {
+        public Nested nested;
+    }
+
+    class Nested {
+        public String value;
+    }
+    // CHECKSTYLE ON
+
+    @Qualifier
+    @java.lang.annotation.Target(ElementType.METHOD)
+    @Retention(RetentionPolicy.CLASS)
+    public @interface SelectMe {
+    }
+}

processor/src/test/java/org/mapstruct/ap/test/selection/qualifier/errors/QualfierMessageTest.java

@@ -0,0 +1,90 @@
+/*
+ * 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.selection.qualifier.errors;
+
+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 javax.tools.Diagnostic.Kind.ERROR;
+
+@IssueKey("2135")
+@RunWith(AnnotationProcessorTestRunner.class)
+public class QualfierMessageTest {
+
+    @Test
+    @WithClasses(ErroneousMessageByAnnotationMapper.class)
+    @ExpectedCompilationOutcome(
+        value = CompilationResult.FAILED,
+        diagnostics = {
+            @Diagnostic(
+                type = ErroneousMessageByAnnotationMapper.class,
+                kind = ERROR,
+                line = 19,
+                message = "Qualifier error. No method found annotated with: [ @SelectMe ]. " +
+                    "See https://mapstruct.org/faq/#qualifier for more info."),
+            @Diagnostic(
+                type = ErroneousMessageByAnnotationMapper.class,
+                kind = ERROR,
+                line = 19,
+                messageRegExp = "Can't map property.*")
+
+        }
+    )
+    public void testNoQualifyingMethodByAnnotationFound() {
+    }
+
+    @Test
+    @WithClasses(ErroneousMessageByNamedMapper.class)
+    @ExpectedCompilationOutcome(
+        value = CompilationResult.FAILED,
+        diagnostics = {
+            @Diagnostic(
+                type = ErroneousMessageByNamedMapper.class,
+                kind = ERROR,
+                line = 19,
+                message = "Qualifier error. No method found annotated with @Named#value: [ SelectMe ]. " +
+                    "See https://mapstruct.org/faq/#qualifier for more info."),
+            @Diagnostic(
+                type = ErroneousMessageByNamedMapper.class,
+                kind = ERROR,
+                line = 19,
+                messageRegExp = "Can't map property.*")
+
+        }
+    )
+    public void testNoQualifyingMethodByNamedFound() {
+    }
+
+    @Test
+    @WithClasses(ErroneousMessageByAnnotationAndNamedMapper.class)
+    @ExpectedCompilationOutcome(
+        value = CompilationResult.FAILED,
+        diagnostics = {
+            @Diagnostic(
+                type = ErroneousMessageByAnnotationAndNamedMapper.class,
+                kind = ERROR,
+                line = 19,
+                message =
+                    "Qualifier error. No method found annotated with @Named#value: [ selectMe1 and selectMe2 ], " +
+                        "annotated with [ @SelectMe1 and @SelectMe2 ]. " +
+                        "See https://mapstruct.org/faq/#qualifier for more info."),
+            @Diagnostic(
+                type = ErroneousMessageByAnnotationAndNamedMapper.class,
+                kind = ERROR,
+                line = 19,
+                messageRegExp = "Can't map property.*")
+
+        }
+    )
+    public void testNoQualifyingMethodByAnnotationAndNamedFound() {
+    }
+}