Refactor script infrastructure for easier usage and testability:

- add script annotation for specifying default configuration for a script
- add support for this annotation in the default configurator
- rename configurator accordingly
- add default implementation of the refineConfiguration method
- make property bag class open

libraries/scripting/common/src/kotlin/script/experimental/annotations/scriptAnnotations.kt

@@ -42,3 +42,8 @@ annotation class KotlinScriptEvaluator(
     val evaluator: KClass<out ScriptEvaluator<*>>
 )
 
+@Target(AnnotationTarget.CLASS)
+@Retention(AnnotationRetention.RUNTIME)
+annotation class KotlinScriptDefaultCompilationConfiguration(
+    val compilationConfiguration: KClass<out List<*>> // object or class filled in 0-ary constructor
+)

libraries/scripting/common/src/kotlin/script/experimental/api/scriptConfiguration.kt

@@ -25,6 +25,7 @@ interface ScriptCompilationConfigurator {
         scriptSource: ScriptSource,
         configuration: ScriptCompileConfiguration,
         processedScriptData: ProcessedScriptData = ProcessedScriptData()
-    ): ResultWithDiagnostics<ScriptCompileConfiguration>
+    ): ResultWithDiagnostics<ScriptCompileConfiguration> =
+        defaultConfiguration.asSuccess()
 }
 

libraries/scripting/common/src/kotlin/script/experimental/basic/basicScript.kt

@@ -5,19 +5,33 @@
 
 package kotlin.script.experimental.basic
 
+import kotlin.reflect.full.primaryConstructor
+import kotlin.script.experimental.annotations.KotlinScriptDefaultCompilationConfiguration
 import kotlin.script.experimental.api.*
+import kotlin.script.experimental.util.TypedKey
 
 
-class PassThroughCompilationConfigurator(val environment: ScriptingEnvironment) : ScriptCompilationConfigurator {
+private const val ILLEGAL_CONFIG_ANN_ARG =
+    "Illegal argument to KotlinScriptDefaultCompilationConfiguration annotation: expecting List-derived object or default-constructed class of configuration parameters"
 
-    override val defaultConfiguration = ScriptCompileConfiguration(environment)
+open class AnnotationsBasedCompilationConfigurator(val environment: ScriptingEnvironment) : ScriptCompilationConfigurator {
 
-    override suspend fun refineConfiguration(
-        script: ScriptSource,
-        configuration: ScriptCompileConfiguration,
-        processedScriptData: ProcessedScriptData
-    ): ResultWithDiagnostics<ScriptCompileConfiguration> =
-        configuration.asSuccess()
+    override val defaultConfiguration = run {
+        val base = environment[ScriptingEnvironmentProperties.baseClass]
+        val cfg = base.annotations.filterIsInstance(KotlinScriptDefaultCompilationConfiguration::class.java).flatMap {
+            val params = try {
+                it.compilationConfiguration.objectInstance ?: it.compilationConfiguration.primaryConstructor!!.callBy(emptyMap())
+            } catch (e: Throwable) {
+                throw IllegalArgumentException(ILLEGAL_CONFIG_ANN_ARG, e)
+            }
+            params.forEach {
+                if (it !is Pair<*, *> || it.first !is TypedKey<*>)
+                    throw IllegalArgumentException("$ILLEGAL_CONFIG_ANN_ARG: invalid parameter $it")
+            }
+            params as List<Pair<TypedKey<*>, Any?>>
+        }
+        ScriptCompileConfiguration(environment, cfg)
+    }
 }
 
 class DummyEvaluator<ScriptBase : Any>(val environment: ScriptingEnvironment) : ScriptEvaluator<ScriptBase> {
@@ -28,9 +42,3 @@ class DummyEvaluator<ScriptBase : Any>(val environment: ScriptingEnvironment) :
         ResultWithDiagnostics.Failure("not implemented".asErrorDiagnostics())
 }
 
-// TODO: from org.jetbrains.kotlin.utils.addToStdlib, take it from the stdlib when available
-private inline fun <reified T : Any> Iterable<*>.firstIsInstanceOrNull(): T? {
-    for (element in this) if (element is T) return element
-    return null
-}
-

libraries/scripting/common/src/kotlin/script/experimental/definitions/definitionFromAnnotation.kt

@@ -13,8 +13,8 @@ import kotlin.script.experimental.annotations.KotlinScriptCompilationConfigurato
 import kotlin.script.experimental.annotations.KotlinScriptEvaluator
 import kotlin.script.experimental.annotations.KotlinScriptFileExtension
 import kotlin.script.experimental.api.*
+import kotlin.script.experimental.basic.AnnotationsBasedCompilationConfigurator
 import kotlin.script.experimental.basic.DummyEvaluator
-import kotlin.script.experimental.basic.PassThroughCompilationConfigurator
 import kotlin.script.experimental.util.TypedKey
 
 private const val ERROR_MSG_PREFIX = "Unable to construct script definition: "
@@ -42,7 +42,7 @@ open class ScriptDefinitionFromAnnotatedBaseClass(val environment: ScriptingEnvi
     override val compilationConfigurator =
         baseClass.findAnnotation<KotlinScriptCompilationConfigurator>()?.compilationConfigurator?.instantiateScriptHandler()
                 ?: explicitDefinition?.compilationConfigurator
-                ?: PassThroughCompilationConfigurator::class.instantiateScriptHandler()
+                ?: AnnotationsBasedCompilationConfigurator::class.instantiateScriptHandler()
 
     override val evaluator =
         baseClass.findAnnotation<KotlinScriptEvaluator>()?.evaluator?.instantiateScriptHandler()

libraries/scripting/common/src/kotlin/script/experimental/util/propertyBag.kt

@@ -17,7 +17,7 @@ class TypedKeyDelegate<T> {
 
 fun <T> typedKey() = TypedKeyDelegate<T>()
 
-class ChainedPropertyBag private constructor(private val parent: ChainedPropertyBag?, private val data: Map<TypedKey<*>, Any?>) {
+open class ChainedPropertyBag private constructor(private val parent: ChainedPropertyBag?, private val data: Map<TypedKey<*>, Any?>) {
     constructor(parent: ChainedPropertyBag? = null, pairs: Iterable<Pair<TypedKey<*>, Any?>>) :
             this(parent, HashMap<TypedKey<*>, Any?>().also { it.putAll(pairs) })