#3848: Mark String to number as lossy conversion

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

@@ -474,6 +474,7 @@ public class NativeTypes {
         tmp3.put( Double.class.getName(), 6 );
         tmp3.put( BigInteger.class.getName(), 50 );
         tmp3.put( BigDecimal.class.getName(), 51 );
+        tmp3.put( String.class.getName(), 51 );
         NARROWING_LUT = Collections.unmodifiableMap( tmp3 );
     }
 

processor/src/test/java/org/mapstruct/ap/test/conversion/lossy/CutleryInventoryDto.java

@@ -10,6 +10,7 @@ public class CutleryInventoryDto {
     private short numberOfKnifes;
     private int numberOfForks;
     private byte numberOfSpoons;
+    private int drawerId;
 
     private float approximateKnifeLength;
 
@@ -44,4 +45,12 @@ public class CutleryInventoryDto {
     public void setApproximateKnifeLength(float approximateKnifeLength) {
         this.approximateKnifeLength = approximateKnifeLength;
     }
+
+    public int getDrawerId() {
+        return drawerId;
+    }
+
+    public void setDrawerId(int drawerId) {
+        this.drawerId = drawerId;
+    }
 }

processor/src/test/java/org/mapstruct/ap/test/conversion/lossy/CutleryInventoryEntity.java

@@ -10,6 +10,7 @@ public class CutleryInventoryEntity {
     private int numberOfKnifes;
     private Long numberOfForks;
     private short numberOfSpoons;
+    private String drawerId;
 
     private double approximateKnifeLength;
 
@@ -44,4 +45,12 @@ public class CutleryInventoryEntity {
     public void setApproximateKnifeLength(double approximateKnifeLength) {
         this.approximateKnifeLength = approximateKnifeLength;
     }
+
+    public String getDrawerId() {
+        return drawerId;
+    }
+
+    public void setDrawerId(String drawerId) {
+        this.drawerId = drawerId;
+    }
 }

processor/src/test/java/org/mapstruct/ap/test/conversion/lossy/ErroneousKitchenDrawerMapper6.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.conversion.lossy;
+
+import org.mapstruct.BeanMapping;
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+import org.mapstruct.ReportingPolicy;
+
+@Mapper( typeConversionPolicy = ReportingPolicy.ERROR )
+public interface ErroneousKitchenDrawerMapper6 {
+
+    @BeanMapping( ignoreByDefault = true )
+    @Mapping( target = "drawerId", source = "drawerId" )
+    RegularKitchenDrawerEntity map( OversizedKitchenDrawerDto dto );
+
+}

processor/src/test/java/org/mapstruct/ap/test/conversion/lossy/LossyConversionTest.java

@@ -40,12 +40,14 @@ public class LossyConversionTest {
         dto.setNumberOfKnifes( (short) 7 );
         dto.setNumberOfSpoons( (byte) 3 );
         dto.setApproximateKnifeLength( 3.7f );
+        dto.setDrawerId( 1 );
 
         CutleryInventoryEntity entity = CutleryInventoryMapper.INSTANCE.map( dto );
         assertThat( entity.getNumberOfForks() ).isEqualTo( 5L );
         assertThat( entity.getNumberOfKnifes() ).isEqualTo( 7 );
         assertThat( entity.getNumberOfSpoons() ).isEqualTo( (short) 3 );
         assertThat( entity.getApproximateKnifeLength() ).isCloseTo( 3.7d, withinPercentage( 0.0001d ) );
+        assertThat( entity.getDrawerId() ).isEqualTo( "1" );
     }
 
     @ProcessorTest
@@ -74,6 +76,19 @@ public class LossyConversionTest {
     public void testConversionFromBigIntegerToInteger() {
     }
 
+    @ProcessorTest
+    @WithClasses(ErroneousKitchenDrawerMapper6.class)
+    @ExpectedCompilationOutcome(value = CompilationResult.FAILED,
+            diagnostics = {
+                    @Diagnostic(type = ErroneousKitchenDrawerMapper6.class,
+                            kind = javax.tools.Diagnostic.Kind.ERROR,
+                            line = 17,
+                            message = "Can't map property \"String drawerId\". It has a possibly lossy conversion from "
+                                    + "String to int.")
+            })
+    public void testConversionFromStringToInt() {
+    }
+
     @ProcessorTest
     @WithClasses(ErroneousKitchenDrawerMapper3.class)
     @ExpectedCompilationOutcome(value = CompilationResult.FAILED,

processor/src/test/java/org/mapstruct/ap/test/conversion/lossy/OversizedKitchenDrawerDto.java

@@ -21,6 +21,7 @@ public class OversizedKitchenDrawerDto {
     private Double depth;
     private BigDecimal length;
     private double height;
+    private String drawerId;
 
     public long getNumberOfForks() {
         return numberOfForks;
@@ -70,4 +71,11 @@ public class OversizedKitchenDrawerDto {
         this.height = height;
     }
 
+    public String getDrawerId() {
+        return drawerId;
+    }
+
+    public void setDrawerId(String drawerId) {
+        this.drawerId = drawerId;
+    }
 }

processor/src/test/java/org/mapstruct/ap/test/conversion/lossy/RegularKitchenDrawerEntity.java

@@ -17,6 +17,7 @@ public class RegularKitchenDrawerEntity {
     private float depth;
     private Float length;
     private VerySpecialNumber height;
+    private int drawerId;
 
     public int getNumberOfForks() {
         return numberOfForks;
@@ -66,4 +67,11 @@ public class RegularKitchenDrawerEntity {
         this.height = height;
     }
 
+    public int getDrawerId() {
+        return drawerId;
+    }
+
+    public void setDrawerId(int drawerId) {
+        this.drawerId = drawerId;
+    }
 }