generateFiles via KotlinFileSpecIterable

kotlin-code-generation-test/src/main/kotlin/model/KotlinCompilationCommand.kt

@@ -3,7 +3,7 @@ package io.toolisticon.kotlin.generation.test.model
 import com.squareup.kotlinpoet.ExperimentalKotlinPoetApi
 import com.tschuchort.compiletesting.SourceFile
 import io.toolisticon.kotlin.generation.spec.KotlinFileSpec
-import io.toolisticon.kotlin.generation.spec.KotlinFileSpecs
+import io.toolisticon.kotlin.generation.spec.KotlinFileSpecList
 import io.toolisticon.kotlin.generation.test.KotlinCodeGenerationTest.sourceFile
 import org.jetbrains.kotlin.compiler.plugin.ExperimentalCompilerApi
 
@@ -13,10 +13,10 @@ import org.jetbrains.kotlin.compiler.plugin.ExperimentalCompilerApi
 @ExperimentalKotlinPoetApi
 @ExperimentalCompilerApi
 data class KotlinCompilationCommand(
-  val fileSpecs: KotlinFileSpecs
+  val fileSpecs: KotlinFileSpecList
 ) {
 
-  constructor(fileSpec: KotlinFileSpec) : this(KotlinFileSpecs(fileSpec))
+  constructor(fileSpec: KotlinFileSpec) : this(KotlinFileSpecList(fileSpec))
 
   operator fun plus(fileSpec: KotlinFileSpec) = copy(fileSpecs = fileSpecs + fileSpec)
 

kotlin-code-generation/src/main/kotlin/KotlinCodeGeneration.kt

@@ -21,20 +21,20 @@ import io.toolisticon.kotlin.generation.KotlinCodeGeneration.builder.propertyBui
 import io.toolisticon.kotlin.generation.KotlinCodeGeneration.builder.runtimeExceptionClassBuilder
 import io.toolisticon.kotlin.generation.KotlinCodeGeneration.builder.typeAliasBuilder
 import io.toolisticon.kotlin.generation.KotlinCodeGeneration.builder.valueClassBuilder
-import io.toolisticon.kotlin.generation.KotlinCodeGeneration.className
 import io.toolisticon.kotlin.generation.builder.*
 import io.toolisticon.kotlin.generation.builder.extra.*
 import io.toolisticon.kotlin.generation.builder.extra.DelegateMapValueClassSpecBuilder.Companion.DEFAULT_KEY_TYPE
 import io.toolisticon.kotlin.generation.poet.FormatSpecifier.asCodeBlock
 import io.toolisticon.kotlin.generation.spec.*
 import io.toolisticon.kotlin.generation.spi.KotlinCodeGenerationContext
 import io.toolisticon.kotlin.generation.spi.KotlinCodeGenerationSpiRegistry
+import io.toolisticon.kotlin.generation.spi.KotlinCodeGenerationStrategy
 import io.toolisticon.kotlin.generation.spi.registry.KotlinCodeGenerationServiceLoader
-import io.toolisticon.kotlin.generation.spi.strategy.KotlinFileSpecStrategy
 import io.toolisticon.kotlin.generation.spi.strategy.executeAll
 import io.toolisticon.kotlin.generation.support.SUPPRESS_MEMBER_VISIBILITY_CAN_BE_PRIVATE
 import mu.KLogging
 import kotlin.reflect.KClass
+import kotlin.reflect.full.isSubclassOf
 
 /**
  * Kotlin Code Generation is a wrapper lib for kotlin poet. This is the central class that allows access to builders and tools via simple static helpers.
@@ -559,34 +559,60 @@ object KotlinCodeGeneration : KLogging() {
     const val NBSP = "·"
   }
 
+  /**
+   * Generator Function that takes a context and an input, finds matching strategies and generates source file(s).
+   *
+   * Invokes the contextFactory and calls `generateFiles(context, input)`.
+   *
+   * @param INPUT the type of the input (base source of generation)
+   * @param CONTEXT the context (containing registry, ...) used for generation.
+   * @param input the instance of the input
+   * @param contextFactory factory fn to create the context (containing the spi registry) used for generation from input
+   * @return [KotlinFileSpecList] containing the generated files
+   * @throws IllegalStateException when no matching strategy is found.
+   */
+  inline fun <reified CONTEXT : KotlinCodeGenerationContext<CONTEXT>, reified INPUT : Any> generateFiles(contextFactory: (INPUT) -> CONTEXT, input: INPUT): KotlinFileSpecList = generateFiles(
+    context = contextFactory.invoke(input),
+    input = input
+  )
 
   /**
-   * Generator Function that takes an input and generates source file(s).
+   * Generator Function that takes a context and an input, finds matching strategies and generates source file(s).
    *
    * @param INPUT the type of the input (base source of generation)
    * @param CONTEXT the context (containing registry, ...) used for generation.
-   * @param STRATEGY the [KotlinFileSpecStrategy] to apply (using `executeAll()`
    * @param input the instance of the input
-   * @param contextFactory fn that creates the context based on input.
-   * @return list of [KotlinFileSpec]
-   * @throws IllegalStateException when no strategy is found.
-   */
-  inline fun <INPUT : Any,
-    CONTEXT : KotlinCodeGenerationContext<CONTEXT>,
-    reified STRATEGY : KotlinFileSpecStrategy<CONTEXT, INPUT>> generateFiles(
-    input: INPUT,
-    contextFactory: (INPUT) -> CONTEXT,
-  ): List<KotlinFileSpec> {
-    val context = contextFactory.invoke(input)
-    val strategies: List<STRATEGY> = context.registry.strategies.filter(STRATEGY::class).mapNotNull {
+   * @param context the context (containing the spi registry) used for generation
+   * @return [KotlinFileSpecList] containing the generated files
+   * @throws IllegalStateException when no matching strategy is found.
+   */
+  inline fun <reified CONTEXT : KotlinCodeGenerationContext<CONTEXT>, reified INPUT : Any> generateFiles(context: CONTEXT, input: INPUT): KotlinFileSpecList {
+    val strategyCandidates = context.registry.strategies.filter { it.specType.isSubclassOf(KotlinFileSpecIterable::class) }
+      .filter { it.contextType.isSubclassOf(CONTEXT::class) }
+      .filter { it.inputType.isSubclassOf(INPUT::class) }
+      .map {
+        @Suppress("UNCHECKED_CAST")
+        it as KotlinCodeGenerationStrategy<CONTEXT, INPUT, KotlinFileSpecIterable>
+      }
+    // find all matching strategies
+    val matchingStrategies: List<KotlinCodeGenerationStrategy<CONTEXT, INPUT, KotlinFileSpecIterable>> = strategyCandidates.mapNotNull {
       if (it.test(context, input)) {
         it
       } else {
         logger.info { "strategy-filter: removing ${it.name}" }
         null
       }
+    }.also {
+      check(it.isNotEmpty()) { "No applicable strategy found/filtered for context=`${CONTEXT::class.simpleName}`, input=`${input::class.simpleName}`." }
+    }
+
+    // generate files
+    val sourceFiles = matchingStrategies.executeAll(context, input).flatten().also {
+      check(it.isNotEmpty()) { "No files where generated for context=`${CONTEXT::class.simpleName}`, input=`${input::class.simpleName}`." }
     }
-    check(strategies.isNotEmpty()) { "No applicable strategy found/filtered for `${STRATEGY::class}`." }
-    return context.registry.strategies.filter(STRATEGY::class).executeAll(context, input)
+
+    // wrap to spec list
+    return KotlinFileSpecList(sourceFiles)
   }
+
 }

kotlin-code-generation/src/main/kotlin/spec/KotlinFileSpec.kt

@@ -11,7 +11,7 @@ import kotlin.reflect.KClass
  */
 data class KotlinFileSpec(
   private val spec: FileSpec
-) : KotlinGeneratorSpec<KotlinFileSpec, FileSpec, FileSpecSupplier>, KotlinFileSpecSupplier, TaggableSpec {
+) : KotlinGeneratorSpec<KotlinFileSpec, FileSpec, FileSpecSupplier>, KotlinFileSpecSupplier, TaggableSpec, KotlinFileSpecIterable {
 
   val packageName: String = spec.packageName
   val rootName: String = spec.name
@@ -20,6 +20,8 @@ data class KotlinFileSpec(
   val fqn: String = "$packageName.$rootName"
   val fileName: String = "$fqn.kt"
 
+  override fun iterator(): Iterator<KotlinFileSpec> = listOf(this).listIterator()
+
   override fun spec(): KotlinFileSpec = this
   override fun get(): FileSpec = spec
 }
@@ -35,15 +37,17 @@ interface KotlinFileSpecSupplier : KotlinGeneratorSpecSupplier<KotlinFileSpec>,
  * List that contains multiple [KotlinFileSpec]s.
  */
 @JvmInline
-value class KotlinFileSpecs(private val fileSpecs: List<KotlinFileSpec>) : List<KotlinFileSpec> by fileSpecs {
+value class KotlinFileSpecList(private val fileSpecs: List<KotlinFileSpec>) : List<KotlinFileSpec> by fileSpecs, KotlinFileSpecIterable {
   companion object {
 
     /**
      * Empty Specs.
      */
-    val EMPTY = KotlinFileSpecs(emptyList())
+    val EMPTY = KotlinFileSpecList(emptyList())
+
+    fun collect(vararg fns: () -> KotlinFileSpec) = collect(fns.toList())
 
-    fun collect(vararg fns: () -> KotlinFileSpec) = fns.fold(EMPTY) { acc, cur -> acc + cur() }
+    fun collect(specs: List<() -> KotlinFileSpec>) = specs.fold(EMPTY) { acc, cur -> acc + cur() }
   }
 
   /**
@@ -52,13 +56,12 @@ value class KotlinFileSpecs(private val fileSpecs: List<KotlinFileSpec>) : List<
   constructor(fileSpec: KotlinFileSpec) : this(listOf(fileSpec))
 
   /**
-   * Create copy of this list and add new spec.
-   */
-  operator fun plus(fileSpec: KotlinFileSpec) = KotlinFileSpecs(fileSpecs + fileSpec)
-
-  /**
-   * Create copy of this list and add all others.
+   * Create copy of this list and add new spec(s).
    */
-  operator fun plus(other: KotlinFileSpecs) = other.fold(this, KotlinFileSpecs::plus)
-
+  operator fun plus(fileSpec: KotlinFileSpecIterable) = KotlinFileSpecList(fileSpecs + fileSpec)
 }
+
+/**
+ * Iterable that provides instances of [KotlinFileSpec].
+ */
+sealed interface KotlinFileSpecIterable : Iterable<KotlinFileSpec>

kotlin-code-generation/src/main/kotlin/spi/KotlinCodeGenerationContext.kt

@@ -39,3 +39,6 @@ interface KotlinCodeGenerationContext<SELF : KotlinCodeGenerationContext<SELF>>
     processorType: KClass<PROCESSOR>
   ): List<PROCESSOR> = registry.processors.filterIsInstance(processorType.java)
 }
+
+@OptIn(ExperimentalKotlinPoetApi::class)
+fun interface KotlinCodeGenerationContextFactory<CONTEXT : KotlinCodeGenerationContext<CONTEXT>, INPUT : Any> : (INPUT) -> CONTEXT

kotlin-code-generation/src/main/kotlin/spi/processor/KotlinCodeGenerationProcessorList.kt

@@ -3,7 +3,6 @@ package io.toolisticon.kotlin.generation.spi.processor
 import com.squareup.kotlinpoet.ExperimentalKotlinPoetApi
 import io.toolisticon.kotlin.generation.spi.KotlinCodeGenerationContext
 import io.toolisticon.kotlin.generation.spi.KotlinCodeGenerationProcessor
-import io.toolisticon.kotlin.generation.spi.KotlinCodeGenerationStrategy
 import io.toolisticon.kotlin.generation.spi.UnboundKotlinCodeGenerationProcessor
 import kotlin.reflect.KClass
 
@@ -12,22 +11,32 @@ import kotlin.reflect.KClass
  */
 @ExperimentalKotlinPoetApi
 @JvmInline
-value class KotlinCodeGenerationProcessorList(val list: List<UnboundKotlinCodeGenerationProcessor>) :
-  List<UnboundKotlinCodeGenerationProcessor> by list {
+value class KotlinCodeGenerationProcessorList(
+  @PublishedApi
+  internal val list: List<UnboundKotlinCodeGenerationProcessor>
+) : List<UnboundKotlinCodeGenerationProcessor> by list {
 
   constructor(vararg processors: UnboundKotlinCodeGenerationProcessor) : this(processors.toList())
 
   /**
    * Filter the current list and return instances of given type.
-   * @param strategyType defining which concrete implementations to use
-   * @return list containing only instances of given [strategyType]
+   *
+   * @param processorType defining which concrete implementations to use
+   * @return list containing only instances of given [processorType]
    */
   fun <PROCESSOR : KotlinCodeGenerationProcessor<CONTEXT, INPUT, BUILDER>, CONTEXT : KotlinCodeGenerationContext<CONTEXT>, INPUT : Any, BUILDER : Any> filter(
     processorType: KClass<PROCESSOR>
   ): List<PROCESSOR> {
     return list.filterIsInstance(processorType.java)
   }
 
+  /**
+   * Filter the current list and return instances of given type.
+   * @return list containing only instances of reified type.
+   */
+  inline fun <reified PROCESSOR : KotlinCodeGenerationProcessor<CONTEXT, INPUT, SPEC>, CONTEXT : KotlinCodeGenerationContext<CONTEXT>, INPUT : Any, SPEC : Any> filter() = filter(PROCESSOR::class)
+
+
   override fun toString(): String = "KotlinCodeGenerationProcessorList(processors=${list.map { it.name }})"
 }
 

kotlin-code-generation/src/main/kotlin/spi/strategy/KotlinCodeGenerationStrategyList.kt

@@ -11,13 +11,16 @@ import kotlin.reflect.KClass
  */
 @ExperimentalKotlinPoetApi
 @JvmInline
-value class KotlinCodeGenerationStrategyList(private val list: List<UnboundKotlinCodeGenerationStrategy>) :
-  List<UnboundKotlinCodeGenerationStrategy> by list {
+value class KotlinCodeGenerationStrategyList(
+  @PublishedApi
+  internal val list: List<UnboundKotlinCodeGenerationStrategy>
+) : List<UnboundKotlinCodeGenerationStrategy> by list {
 
   constructor(vararg strategy: UnboundKotlinCodeGenerationStrategy) : this(strategy.toList())
 
   /**
    * Filter the current list and return instances of given type.
+   *
    * @param strategyType defining which concrete implementations to use
    * @return list containing only instances of given [strategyType]
    */
@@ -27,6 +30,12 @@ value class KotlinCodeGenerationStrategyList(private val list: List<UnboundKotli
     return list.filterIsInstance(strategyType.java)
   }
 
+  /**
+   * Filter the current list and return instances of given type.
+   * @return list containing only instances of reified type.
+   */
+  inline fun <reified STRATEGY : KotlinCodeGenerationStrategy<CONTEXT, INPUT, SPEC>, CONTEXT : KotlinCodeGenerationContext<CONTEXT>, INPUT : Any, SPEC : Any> filter() = filter(STRATEGY::class)
+
   override fun toString(): String = "KotlinCodeGenerationStrategyList(strategies=${list.map { it.name }})"
 }
 
@@ -40,6 +49,4 @@ fun <STRATEGY : KotlinCodeGenerationStrategy<CONTEXT, INPUT, SPEC>, CONTEXT : Ko
 fun <STRATEGY : KotlinCodeGenerationStrategy<CONTEXT, INPUT, SPEC>, CONTEXT : KotlinCodeGenerationContext<CONTEXT>, INPUT : Any, SPEC : Any> List<STRATEGY>.executeAll(
   context: CONTEXT,
   input: INPUT
-): List<SPEC> = map {
-  it.execute(context, input)
-}.filterNotNull()
+): List<SPEC> = mapNotNull { it.execute(context, input) }

kotlin-code-generation/src/main/kotlin/spi/strategy/KotlinFileSpecsStrategy.kt → kotlin-code-generation/src/main/kotlin/spi/strategy/KotlinFileSpecListStrategy.kt

@@ -1,31 +1,33 @@
 package io.toolisticon.kotlin.generation.spi.strategy
 
 import com.squareup.kotlinpoet.ExperimentalKotlinPoetApi
-import io.toolisticon.kotlin.generation.spec.KotlinFileSpecs
+import io.toolisticon.kotlin.generation.spec.KotlinFileSpecList
 import io.toolisticon.kotlin.generation.spi.KotlinCodeGenerationContext
 import io.toolisticon.kotlin.generation.spi.KotlinCodeGenerationSpi
 import kotlin.reflect.KClass
 
 /**
  * Used to implement a [io.toolisticon.kotlin.generation.spi.KotlinCodeGenerationStrategy]
- * that will generate multiple [io.toolisticon.kotlin.generation.spec.KotlinFileSpec]s wrapped in [KotlinFileSpecs].
+ * that will generate multiple [io.toolisticon.kotlin.generation.spec.KotlinFileSpec]s wrapped in [KotlinFileSpecList].
  *
  * Implementations should override the `invoke` function to call multiple [KotlinFileSpecStrategy]s and collect the
  * results.
  */
 @ExperimentalKotlinPoetApi
-abstract class KotlinFileSpecsStrategy<CONTEXT : KotlinCodeGenerationContext<CONTEXT>, INPUT : Any>(
+abstract class KotlinFileSpecListStrategy<CONTEXT : KotlinCodeGenerationContext<CONTEXT>, INPUT : Any>(
   contextType: KClass<CONTEXT>,
   override val inputType: KClass<INPUT>,
   order: Int = KotlinCodeGenerationSpi.DEFAULT_ORDER,
-) : KotlinCodeGenerationStrategyBase<CONTEXT, INPUT, KotlinFileSpecs>(
+) : KotlinFileSpecIterableStrategy<CONTEXT, INPUT, KotlinFileSpecList>(
   contextType = contextType,
   inputType = inputType,
-  specType = KotlinFileSpecs::class,
+  specType = KotlinFileSpecList::class,
   order = order
 ) {
 
-  abstract override fun invoke(context: CONTEXT, input: INPUT): KotlinFileSpecs
+  abstract override fun invoke(context: CONTEXT, input: INPUT): KotlinFileSpecList
 
   override fun test(context: CONTEXT, input: Any): Boolean = super.test(context, input)
+
+  override fun execute(context: CONTEXT, input: INPUT): KotlinFileSpecList = super.execute(context, input) ?: KotlinFileSpecList.EMPTY
 }

kotlin-code-generation/src/main/kotlin/spi/strategy/KotlinFileSpecStrategy.kt

@@ -15,7 +15,7 @@ abstract class KotlinFileSpecStrategy<CONTEXT : KotlinCodeGenerationContext<CONT
   contextType: KClass<CONTEXT>,
   override val inputType: KClass<INPUT>,
   order: Int = KotlinCodeGenerationSpi.DEFAULT_ORDER,
-) : KotlinCodeGenerationStrategyBase<CONTEXT, INPUT, KotlinFileSpec>(
+) : KotlinFileSpecIterableStrategy<CONTEXT, INPUT, KotlinFileSpec>(
   contextType = contextType,
   inputType = inputType,
   specType = KotlinFileSpec::class,

kotlin-code-generation/src/main/kotlin/spi/strategy/_abstract.kt

@@ -0,0 +1,29 @@
+package io.toolisticon.kotlin.generation.spi.strategy
+
+import com.squareup.kotlinpoet.ExperimentalKotlinPoetApi
+import io.toolisticon.kotlin.generation.spec.KotlinFileSpecIterable
+import io.toolisticon.kotlin.generation.spi.KotlinCodeGenerationContext
+import io.toolisticon.kotlin.generation.spi.KotlinCodeGenerationSpi
+import kotlin.reflect.KClass
+
+/**
+ * Base class for [KotlinFileSpecStrategy] and [KotlinFileSpecListStrategy] so we can join single and multi results
+ * during generation.
+ */
+@ExperimentalKotlinPoetApi
+sealed class KotlinFileSpecIterableStrategy<CONTEXT : KotlinCodeGenerationContext<CONTEXT>, INPUT : Any, SPEC : KotlinFileSpecIterable>(
+  contextType: KClass<CONTEXT>,
+  override val inputType: KClass<INPUT>,
+  specType: KClass<SPEC>,
+  order: Int = KotlinCodeGenerationSpi.DEFAULT_ORDER,
+) : KotlinCodeGenerationStrategyBase<CONTEXT, INPUT, SPEC>(
+  contextType = contextType,
+  inputType = inputType,
+  specType = specType,
+  order = order
+) {
+
+  abstract override fun invoke(context: CONTEXT, input: INPUT): SPEC
+
+  override fun test(context: CONTEXT, input: Any): Boolean = super.test(context, input)
+}