Annotation processor for [at]bounded

arrow-annotations-processor/src/main/java/arrow/optics/BoundLensGenerator.kt

@@ -0,0 +1,34 @@
+package arrow.optics
+
+import arrow.common.utils.fullName
+import me.eugeniomarletti.kotlin.metadata.escapedClassName
+import java.io.File
+
+class BoundLensGenerator(
+        private val annotatedList: Collection<AnnotatedOptic>,
+        private val generatedDir: File
+) {
+
+    private val boundLens = "arrow.optics.BoundSetter"
+
+    fun generate() = annotatedList.map(this::processElement)
+            .map { (element, funs) ->
+                "${boundAnnotationClass.simpleName}.${element.classData.`package`}.${element.type.simpleName.toString().toLowerCase()}.kt" to
+                        funs.joinToString(prefix = "package ${element.classData.`package`.escapedClassName}\n\n", separator = "\n")
+            }.forEach { (name, fileString) -> File(generatedDir, name).writeText(fileString) }
+
+    private fun String.toUpperCamelCase(): String = split(" ").joinToString("", transform = String::capitalize)
+
+    private fun processElement(annotatedOptic: AnnotatedOptic): Pair<AnnotatedOptic, List<String>> =
+            annotatedOptic to annotatedOptic.targets.map { variable ->
+                val sourceClassName = annotatedOptic.classData.fullName.escapedClassName
+                val sourceName = annotatedOptic.type.simpleName.toString().decapitalize()
+                val targetClassName = variable.fullName
+                val targetName = variable.paramName
+
+                """
+                    |val <T> $boundLens<T, $sourceClassName>.$targetName: $boundLens<T, $targetClassName> get() = this.compose($sourceName${targetName.toUpperCamelCase()}())
+                    """.trimMargin()
+            }
+
+}

arrow-optics/src/main/kotlin/arrow/optics/bound.kt

@@ -1,6 +1,8 @@
 package arrow.optics
 
-class BoundSetter<S, A>(private val value: S, private val setter: Setter<S, A>) {
+import arrow.core.Option
+
+class BoundSetter<S, A>(val value: S, val setter: Setter<S, A>) {
 
     fun <T> compose(other: Setter<A, T>)    = BoundSetter(value, setter + other)
     fun <T> compose(other: Optional<A, T>)  = BoundSetter(value, setter + other)
@@ -14,4 +16,9 @@ class BoundSetter<S, A>(private val value: S, private val setter: Setter<S, A>)
     fun set(a: A) = setter.set(value, a)
 }
 
-fun <T> T.setter() = BoundSetter(this, Setter.id())
+fun <T> T.setter() = BoundSetter(this, Setter.id())
+
+val <T, A> BoundSetter<T, A?>.nullable get(): BoundSetter<T, A> = compose(nullableOptional())
+
+val <T, A> BoundSetter<T, Option<A>>.some get(): BoundSetter<T, A> = compose(optionOptional())
+

arrow-optics/src/test/kotlin/arrow/optics/BoundedTest.kt

@@ -0,0 +1,30 @@
+package arrow.optics
+
+import arrow.bounded
+import arrow.lenses
+import io.kotlintest.matchers.shouldBe
+import io.kotlintest.specs.StringSpec
+
+@bounded data class Street(val number: Int, val name: String)
+@bounded data class Address(val city: String, val street: Street)
+@bounded data class Company(val name: String, val address: Address)
+@bounded data class Employee(val name: String, val company: Company?)
+
+//TODO: Rewrite to annotation processor test when multiple file support is implemented
+class BoundedTest: StringSpec() {
+
+    init {
+
+        "@bounded classes are generated properly" {
+
+            val employee = Employee("John Doe", Company("Kategory", Address("Functional city", Street(42, "lambda street"))))
+            val newEmployee = employee.setter().company.nullable.address.street.name.modify { it.capitalize() }
+
+            val expected = Employee("John Doe", Company("Kategory", Address("Functional city", Street(42, "Lambda street"))))
+
+            newEmployee shouldBe expected
+        }
+
+    }
+
+}

modules/core/arrow-annotations-processor/build.gradle

@@ -1,6 +1,3 @@
-import org.gradle.internal.jvm.Jvm
-import org.gradle.api.GradleException
-
 apply plugin: 'kotlin'
 apply plugin: 'kotlin-kapt'
 

modules/core/arrow-annotations-processor/src/main/java/arrow/optics/AnnotationInfo.kt

@@ -1,5 +1,6 @@
 package arrow.optics
 
+import arrow.bounded
 import arrow.isos
 import arrow.lenses
 import arrow.optionals
@@ -23,4 +24,9 @@ val isosAnnotationTarget = "data class"
 val optionalsAnnotationKClass = optionals::class
 val optionalsAnnotationClass = optionalsAnnotationKClass.java
 val optionalsAnnotationName = "@" + optionalsAnnotationClass.simpleName
-val optionalsAnnotationTarget = "data class"
+val optionalsAnnotationTarget = "data class"
+
+val boundAnnotationKClass = bounded::class
+val boundAnnotationClass = boundAnnotationKClass.java
+val boundAnnotationName = "@" + boundAnnotationClass.simpleName
+val boundAnnotationTarget = "data class"

modules/core/arrow-annotations/src/main/java/arrow/optics.kt

@@ -18,3 +18,7 @@ annotation class isos
 @Retention(SOURCE)
 @Target(CLASS)
 annotation class optionals
+
+@Retention(SOURCE)
+@Target(CLASS)
+annotation class bounded

modules/optics/arrow-optics/build.gradle

@@ -8,6 +8,7 @@ dependencies {
 
     compile project(':arrow-annotations')
     kapt project(':arrow-annotations-processor')
+    kaptTest project(':arrow-annotations-processor')
 }
 
 apply from: rootProject.file('gradle/gradle-mvn-push.gradle')