From 306664fb6aa97edc0ee2f8a1f659b2cad436d684 Mon Sep 17 00:00:00 2001
From: Jesse Wilson <jwilson@squareup.com>
Date: Sun, 9 Sep 2018 17:03:39 -0400
Subject: [PATCH] Call Types.newParameterizedTypeWithOwner when necessary.

Otherwise we crash with an exception attempting to create an adapter
for an enclosed type that has a type parameter.

I ran into this looking for a test case for issue 615.
https://github.com/square/moshi/issues/615
---
 .../moshi/kotlin/codegen/TypeRenderer.kt      | 21 +++++---
 .../kotlin/codgen/GeneratedAdaptersTest.kt    | 50 +++++++++++++++++++
 2 files changed, 65 insertions(+), 6 deletions(-)

diff --git a/kotlin/codegen/src/main/java/com/squareup/moshi/kotlin/codegen/TypeRenderer.kt b/kotlin/codegen/src/main/java/com/squareup/moshi/kotlin/codegen/TypeRenderer.kt
index d6957fc..1beebb4 100644
--- a/kotlin/codegen/src/main/java/com/squareup/moshi/kotlin/codegen/TypeRenderer.kt
+++ b/kotlin/codegen/src/main/java/com/squareup/moshi/kotlin/codegen/TypeRenderer.kt
@@ -66,12 +66,21 @@ abstract class TypeRenderer {
               Types::class,
               render(typeName.typeArguments[0].objectType()))
         } else {
-          val placeholders = typeName.typeArguments.joinToString(", ") { "%L" }
-          CodeBlock.of(
-              "%T.newParameterizedType(%T::class.java, $placeholders)",
-              Types::class,
-              typeName.rawType.objectType(),
-              *(typeName.typeArguments.map { render(it.objectType()) }.toTypedArray()))
+          val builder = CodeBlock.builder().apply {
+            add("%T.", Types::class)
+            val enclosingClassName = typeName.rawType.enclosingClassName()
+            if (enclosingClassName != null) {
+              add("newParameterizedTypeWithOwner(%L, ", render(enclosingClassName))
+            } else {
+              add("newParameterizedType(")
+            }
+            add("%T::class.java", typeName.rawType.objectType())
+            for (typeArgument in typeName.typeArguments) {
+              add(", %L", render(typeArgument.objectType()))
+            }
+            add(")")
+          }
+          builder.build()
         }
       }
 
diff --git a/kotlin/tests/src/test/kotlin/com/squareup/moshi/kotlin/codgen/GeneratedAdaptersTest.kt b/kotlin/tests/src/test/kotlin/com/squareup/moshi/kotlin/codgen/GeneratedAdaptersTest.kt
index ab9a92d..c0cf8c0 100644
--- a/kotlin/tests/src/test/kotlin/com/squareup/moshi/kotlin/codgen/GeneratedAdaptersTest.kt
+++ b/kotlin/tests/src/test/kotlin/com/squareup/moshi/kotlin/codgen/GeneratedAdaptersTest.kt
@@ -28,6 +28,7 @@ import com.squareup.moshi.ToJson
 import com.squareup.moshi.Types
 import org.assertj.core.api.Assertions.assertThat
 import org.intellij.lang.annotations.Language
+import org.junit.Assert.assertNull
 import org.junit.Assert.fail
 import org.junit.Ignore
 import org.junit.Test
@@ -901,6 +902,55 @@ class GeneratedAdaptersTest {
     }
   }
 
+  @Test fun propertyIsNothing() {
+    val moshi = Moshi.Builder()
+        .add(NothingAdapter())
+        .build()
+    val jsonAdapter = moshi.adapter(HasNothingProperty::class.java).serializeNulls()
+
+    val toJson = HasNothingProperty()
+    toJson.a = "1"
+    assertThat(jsonAdapter.toJson(toJson)).isEqualTo("""{"a":"1","b":null}""")
+
+    val fromJson = jsonAdapter.fromJson("""{"a":"3","b":null}""")!!
+    assertThat(fromJson.a).isEqualTo("3")
+    assertNull(fromJson.b)
+  }
+
+  class NothingAdapter {
+    @ToJson fun toJson(jsonWriter: JsonWriter, unused: Nothing?) {
+      jsonWriter.nullValue()
+    }
+
+    @FromJson fun fromJson(jsonReader: JsonReader) : Nothing? {
+      jsonReader.skipValue()
+      return null
+    }
+  }
+
+  @JsonClass(generateAdapter = true)
+  class HasNothingProperty {
+    var a: String? = null
+    var b: Nothing? = null
+  }
+
+  @Test fun enclosedParameterizedType() {
+    val jsonAdapter = moshi.adapter(HasParameterizedProperty::class.java)
+
+    assertThat(jsonAdapter.toJson(HasParameterizedProperty(Twins("1", "2"))))
+        .isEqualTo("""{"twins":{"a":"1","b":"2"}}""")
+
+    val hasParameterizedProperty = jsonAdapter.fromJson("""{"twins":{"a":"3","b":"4"}}""")!!
+    assertThat(hasParameterizedProperty.twins.a).isEqualTo("3")
+    assertThat(hasParameterizedProperty.twins.b).isEqualTo("4")
+  }
+
+  @JsonClass(generateAdapter = true)
+  class Twins<T>(var a: T, var b: T)
+
+  @JsonClass(generateAdapter = true)
+  class HasParameterizedProperty(val twins: Twins<String>)
+
   @JsonQualifier
   annotation class Uppercase(val inFrench: Boolean, val onSundays: Boolean = false)