Fixed #262 (#278)

Author: stefankoppier

compiler-plugin/src/main/kotlin/tech/mappie/ir/preprocessing/DefinitionsCollector.kt

@@ -16,6 +16,9 @@ import tech.mappie.ir.util.BaseVisitor
 import tech.mappie.exceptions.MappiePanicException.Companion.panic
 import tech.mappie.ir.resolving.MappieDefinition
 import tech.mappie.ir.resolving.RequestResolverContext
+import tech.mappie.ir.util.isSubclassOf
+import tech.mappie.ir.util.mappieSuperType
+import tech.mappie.ir.util.mappieType
 
 // TODO: we should collect al publicly visible, and add those during resolving that are visible from the current scope.
 class DefinitionsCollector(val context: MappieContext) {
@@ -64,8 +67,10 @@ class ProjectMappieDefinitionsCollector(val context: MappieContext) : BaseVisito
     override fun visitClass(declaration: IrClass, data: Unit) =
         buildList {
             if (context.shouldGenerateCode(declaration)) {
-                (declaration.superTypes.single() as? IrSimpleType)?.let {
-                    add(MappieDefinition(declaration))
+                context(context) {
+                    declaration.mappieSuperType()?.let {
+                        add(MappieDefinition(declaration))
+                    }
                 }
             }
             addAll(declaration.declarations.filterIsInstance<IrClass>().flatMap { it.accept(data) })

compiler-plugin/src/main/kotlin/tech/mappie/ir/util/Ir.kt

@@ -21,9 +21,16 @@ import org.jetbrains.kotlin.ir.types.getClass
 import org.jetbrains.kotlin.ir.util.SYNTHETIC_OFFSET
 import org.jetbrains.kotlin.ir.util.isNullable
 import org.jetbrains.kotlin.ir.util.erasedUpperBound
+import org.jetbrains.kotlin.ir.util.isStrictSubtypeOfClass
 import org.jetbrains.kotlin.name.Name
+import tech.mappie.MappieContext
+import tech.mappie.referenceMappieClass
 import tech.mappie.util.*
 
+context (context: MappieContext)
+fun IrClass.mappieSuperType(): IrType? =
+    allSuperTypes().singleOrNull { it.isStrictSubtypeOfClass(context.referenceMappieClass()) }
+
 fun IrClass.isSubclassOf(clazz: IrClassSymbol) =
     allSuperTypes().any { it.erasedUpperBound == clazz.defaultType.getClass()!! }
 

compiler-plugin/src/test/kotlin/tech/mappie/testing/MapperInheritanceTest.kt

@@ -30,4 +30,26 @@ class MapperInheritanceTest : MappieTestCase() {
                 .isEqualTo(Output("test"))
         }
     }
+
+    @Test
+    fun `inherit with interface mapper should succeed`() {
+        compile {
+            file("Mapper.kt",
+                """
+                import tech.mappie.api.ObjectMappie
+                import tech.mappie.testing.MapperInheritanceTest.*
+
+                class Mapper : ObjectMappie<Input, Output>(), AutoCloseable {
+                    override fun close() { }
+                }
+                """
+            )
+        } satisfies  {
+            isOk()
+            hasNoWarningsOrErrors()
+
+            assertThat(objectMappie<Input, Output>().map(Input("test")))
+                .isEqualTo(Output("test"))
+        }
+    }
 }

website/src/changelog.md

@@ -9,6 +9,7 @@ changelog:
       - "Added support for kotlinx-datetime to JVM mappers, which can be imported via a separate dependency."
       - "Fixed check of runtime usage of of mapping DSL for multiple object mappie."
       - "[#264](https://github.com/Mr-Mappie/mappie/issues/264) Fix compilation error with ObjectMappie5."
+      - "[#262](https://github.com/Mr-Mappie/mappie/issues/262) Fixed compilation error when mapper inherits from more than a Mappie subclass."
       - "Minor performance enhancements - by @ErwinOlie."
       - "Fix for missing reporting when both a mapper and its generated mapper have issues - by @ErwinOlie."
       - "Improved reporting of type parameters - by @ErwinOlie."