From 77b39bd77c4264d89b8096e47dbc3bbe8222c167 Mon Sep 17 00:00:00 2001
From: David Denton <denton.david@gmail.com>
Date: Wed, 3 Jan 2024 10:46:58 +0000
Subject: [PATCH] add objects

---
 .../dev/forkhandles/lens/AbstractLensProp.kt  |  5 ++--
 .../kotlin/dev/forkhandles/lens/MapWrapper.kt |  9 +++++++
 .../dev/forkhandles/lens/PropertySet.kt       |  4 ---
 .../dev/forkhandles/lens/MapWrapperTest.kt    | 27 ++++++++++++-------
 4 files changed, 29 insertions(+), 16 deletions(-)
 create mode 100644 lens4k/src/main/kotlin/dev/forkhandles/lens/MapWrapper.kt

diff --git a/lens4k/src/main/kotlin/dev/forkhandles/lens/AbstractLensProp.kt b/lens4k/src/main/kotlin/dev/forkhandles/lens/AbstractLensProp.kt
index d0459d9..c2f1449 100644
--- a/lens4k/src/main/kotlin/dev/forkhandles/lens/AbstractLensProp.kt
+++ b/lens4k/src/main/kotlin/dev/forkhandles/lens/AbstractLensProp.kt
@@ -16,9 +16,10 @@ abstract class AbstractLensProp<IN, OUT>(
                 thisRef.existsFn(property.name) -> throw NoSuchElementException("Value for field <${property.name}> is null")
                 else -> throw NoSuchElementException("Field <${property.name}> is missing")
             }
-            (property.returnType.jvmErasure == result.javaClass.kotlin) -> result as OUT
+            property.returnType.jvmErasure.isInstance(result) -> result as OUT
 
-            else -> throw NoSuchElementException("Value for field <${property.name}> is not a ${property.returnType.jvmErasure}")
+            else -> throw NoSuchElementException("Value for field <${property.name}> is not a ${property.returnType.jvmErasure} but ${result.javaClass.kotlin}")
         }
     }
 }
+
diff --git a/lens4k/src/main/kotlin/dev/forkhandles/lens/MapWrapper.kt b/lens4k/src/main/kotlin/dev/forkhandles/lens/MapWrapper.kt
new file mode 100644
index 0000000..bb47c64
--- /dev/null
+++ b/lens4k/src/main/kotlin/dev/forkhandles/lens/MapWrapper.kt
@@ -0,0 +1,9 @@
+package dev.forkhandles.lens
+
+abstract class MapWrapper(private val map: Map<String, Any?>) {
+    class Field<OUT> : AbstractLensProp<MapWrapper, OUT>({ map.containsKey(it) }, { map[it] })
+    class ListField<IN, OUT>(mapFn: (IN) -> OUT) : AbstractLensProp<MapWrapper, List<OUT>>({ map.containsKey(it) }, {
+        @Suppress("UNCHECKED_CAST")
+        (map[it] as List<IN>).map(mapFn)
+    })
+}
diff --git a/lens4k/src/main/kotlin/dev/forkhandles/lens/PropertySet.kt b/lens4k/src/main/kotlin/dev/forkhandles/lens/PropertySet.kt
index b384a0a..30cf1ab 100644
--- a/lens4k/src/main/kotlin/dev/forkhandles/lens/PropertySet.kt
+++ b/lens4k/src/main/kotlin/dev/forkhandles/lens/PropertySet.kt
@@ -30,7 +30,3 @@ object PropertySets {
             injector = { subject, value -> subject.toMutableMap().apply { this[propertyName] = value } }
         )
 }
-
-abstract class MapWrapper(private val map: Map<String, Any?>) {
-    class Primitive<OUT> : AbstractLensProp<MapWrapper, OUT>({ map.containsKey(it) }, { map[it] })
-}
diff --git a/lens4k/src/test/kotlin/dev/forkhandles/lens/MapWrapperTest.kt b/lens4k/src/test/kotlin/dev/forkhandles/lens/MapWrapperTest.kt
index 0d39a05..890e2ae 100644
--- a/lens4k/src/test/kotlin/dev/forkhandles/lens/MapWrapperTest.kt
+++ b/lens4k/src/test/kotlin/dev/forkhandles/lens/MapWrapperTest.kt
@@ -8,14 +8,19 @@ import strikt.assertions.message
 
 class MapWrapperTest {
 
+    class SubMap(propertySet: Map<String, Any?>) : MapWrapper(propertySet) {
+        val stringField by Field<String>()
+    }
+
     class MapBacked(propertySet: Map<String, Any?>) : MapWrapper(propertySet) {
-        val stringField by Primitive<String>()
-        val booleanField by Primitive<Boolean>()
-        val intField by Primitive<Int>()
-        val longField by Primitive<Long>()
-        val decimalField by Primitive<Double>()
-        val notAStringField by Primitive<String>()
-        val noSuchField by Primitive<String>()
+        val stringField by Field<String>()
+        val booleanField by Field<Boolean>()
+        val intField by Field<Int>()
+        val longField by Field<Long>()
+        val decimalField by Field<Double>()
+        val notAStringField by Field<String>()
+        val noSuchField by Field<String>()
+        val listField by ListField(::SubMap)
     }
 
     @Test
@@ -28,8 +33,9 @@ class MapWrapperTest {
                 "longField" to Long.MAX_VALUE,
                 "decimalField" to 1.1234,
                 "notAStringField" to 123,
-                "objectField" to mapOf(
-                    "stringField" to "string"
+                "listField" to listOf(
+                    mapOf("stringField" to "string1"),
+                    mapOf("stringField" to "string2"),
                 )
             )
         )
@@ -39,7 +45,8 @@ class MapWrapperTest {
         expectThat(mapBacked.intField).isEqualTo(123)
         expectThat(mapBacked.longField).isEqualTo(Long.MAX_VALUE)
         expectThat(mapBacked.decimalField).isEqualTo(1.1234)
-        expectThrows<NoSuchElementException> { mapBacked.notAStringField }.message.isEqualTo("Value for field <notAStringField> is not a class kotlin.String")
+        expectThat(mapBacked.listField.map { it.stringField }).isEqualTo(listOf("string1", "string2"))
+        expectThrows<NoSuchElementException> { mapBacked.notAStringField }.message.isEqualTo("Value for field <notAStringField> is not a class kotlin.String but class kotlin.Int")
         expectThrows<NoSuchElementException> { mapBacked.noSuchField }.message.isEqualTo("Field <noSuchField> is missing")
     }
 }