Merge pull request #32 from tobrun/kdz-retain-imports

Add import support for default parameters

Author: kiryldz

README.md

@@ -28,8 +28,8 @@ And you will have to include the required dependencies:
 
 ```groovy
 dependencies {
-  implementation 'com.github.tobrun.kotlin-data-compat:annotation:0.3.0'
-  ksp 'com.github.tobrun.kotlin-data-compat:processor:0.3.0'
+  implementation 'com.github.tobrun.kotlin-data-compat:annotation:0.4.0'
+  ksp 'com.github.tobrun.kotlin-data-compat:processor:0.4.0'
 }
 ```
 
@@ -41,6 +41,7 @@ Given an exisiting data class:
  - mark class private
  - append `Data` to the class name
  - support default parameters by using `@Default` annotation
+ - support imports for default parameters
  - retain existing class annotations (but not parameters for them)
  - retain existing interfaces
 
@@ -59,7 +60,7 @@ annotation class SampleAnnotation
 @DataCompat
 @SampleAnnotation
 private data class PersonData(
-    @Default("\"John\"")
+    @Default("\"John\" + Date(1580897313933L).toString()", imports = ["java.util.Date"])
     val name: String,
     val nickname: String?,
     @Default("42")
@@ -72,6 +73,7 @@ After compilation, the following class will be generated:
 ```kotlin
 package com.tobrun.`data`.compat.example
 
+import java.util.Date
 import java.util.Objects
 import kotlin.Any
 import kotlin.Boolean
@@ -120,7 +122,7 @@ public class Person private constructor(
      */
     public class Builder {
         @set:JvmSynthetic
-        public var name: String? = "John"
+        public var name: String? = "John" + Date(1580897313933L).toString()
 
         @set:JvmSynthetic
         public var nickname: String? = null

annotation/src/main/kotlin/com/tobrun/datacompat/annotation/Default.kt

@@ -10,7 +10,13 @@ package com.tobrun.datacompat.annotation
  * @param valueAsString exact representation of the default value. E.g. if default [String] is used,
  *  it should be passed here as "\"STRING_VALUE\""; if default [Int] is used, it should be passed
  *  as "INT_VALUE".
+ *
+ * @param imports if default parameter requires additional imports, they should be passed here.
+ *  E.g. `listOf("android.graphics.Color")`
  */
 @Retention(AnnotationRetention.RUNTIME)
 @Target(AnnotationTarget.VALUE_PARAMETER)
-annotation class Default(val valueAsString: String)
+annotation class Default(
+    val valueAsString: String,
+    val imports: Array<String> = []
+)

example/src/main/kotlin/com/tobrun/data/compat/example/PersonData.kt

@@ -15,7 +15,7 @@ annotation class SampleAnnotation
 @DataCompat
 @SampleAnnotation
 private data class PersonData(
-    @Default("\"John\"")
+    @Default("\"John\" + Date(1580897313933L).toString()", imports = ["java.util.Date"])
     val name: String,
     val nickname: String?,
     @Default("42")

processor/src/main/kotlin/com/tobrun/datacompat/DataCompatProcessor.kt

@@ -77,6 +77,7 @@ class DataCompatProcessor(
             val implementedInterfaces = classDeclaration
                 .superTypes
                 .filter { (it.resolve().declaration as? KSClassDeclaration)?.classKind == ClassKind.INTERFACE }
+            val imports = ArrayList<String>()
 
             // Map KSP properties with KoltinPoet TypeNames
             val propertyMap = mutableMapOf<KSPropertyDeclaration, TypeName>()
@@ -219,9 +220,13 @@ class DataCompatProcessor(
             val builderBuilder = TypeSpec.classBuilder("Builder")
             for (property in propertyMap) {
                 val propertyName = property.key.toString()
-                val defaultValue = property.key.annotations
+                val defaultAnnotationsParams = property.key.annotations
                     .firstOrNull { it.annotationType.resolve().toString() == Default::class.simpleName }
-                    ?.arguments?.first()
+                    ?.arguments
+                val defaultValue = defaultAnnotationsParams?.first()
+                defaultAnnotationsParams?.getOrNull(1)?.value?.let {
+                    imports.addAll(it as ArrayList<String>)
+                }
                 val nullableType = property.value.copy(nullable = true)
                 builderBuilder.addProperty(
                     PropertySpec.builder(propertyName, nullableType)
@@ -350,6 +355,14 @@ class DataCompatProcessor(
                 .addType(classBuilder.build())
                 .addFunction(initializerFunctionBuilder.build())
 
+            imports.forEach {
+                fileBuilder
+                    .addImport(
+                        it.split(".").dropLast(1).joinToString("."),
+                        it.split(".").last()
+                    )
+            }
+
             fileBuilder.build().writeTo(codeGenerator = codeGenerator, aggregating = false)
         }
 

processor/src/test/kotlin/com/tobrun/datacompat/DataCompatProcessorTest.kt

@@ -28,7 +28,7 @@ interface EmptyInterface2
 @Deprecated
 @DataCompat
 private data class PersonData(
-    @Default("\"John\"")
+    @Default("\"John\"", ["java.util.Date"])
     val name: String,
     @Default("null")
     val nickname: String?,

processor/src/test/kotlin/com/tobrun/datacompat/SimpleTestContent.kt

@@ -1,6 +1,7 @@
 package com.tobrun.datacompat
 
 internal val expectedSimpleTestContent = """
+    import java.util.Date
     import java.util.Objects
     import kotlin.Any
     import kotlin.Boolean

processor/src/test/kotlin/com/tobrun/datacompat/TestAnnotation.kt

@@ -12,7 +12,7 @@ package com.tobrun.datacompat.annotation
 annotation class DataCompat
 
 @Retention(AnnotationRetention.RUNTIME)
-@Target(AnnotationTarget.CLASS)
-annotation class Default(val valueAsString: String)
+@Target(AnnotationTarget.VALUE_PARAMETER)
+annotation class Default(val valueAsString: String, val importList: Array<String> = [])
     """.trimIndent()
 )