Add new experimental scripting API

libraries/scripting/common/src/kotlin/script/experimental/host/BasicScriptingHost.kt

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+@file:Suppress("unused")
+
+package kotlin.script.experimental.host
+
+import kotlinx.coroutines.experimental.CoroutineScope
+import kotlinx.coroutines.experimental.runBlocking
+import kotlin.script.experimental.api.*
+
+abstract class BasicScriptingHost<ScriptBase : Any>(
+    val configurator: ScriptConfigurator,
+    val compiler: ScriptCompiler,
+    val runner: ScriptRunner<ScriptBase>
+) {
+    open fun <T> runInCoroutineContext(block: suspend CoroutineScope.() -> T): T = runBlocking { block() }
+
+    open fun eval(configuration: ScriptCompileConfiguration, environment: ScriptEvaluationEnvironment): ResultWithDiagnostics<EvaluationResult> =
+        runInCoroutineContext {
+            val compiled = compiler.compile(configuration, configurator)
+            when (compiled) {
+                is ResultWithDiagnostics.Failure -> compiled
+                is ResultWithDiagnostics.Success -> {
+                    val compiledScript = compiled.value!! as CompiledScript<ScriptBase>
+                    runner.run(compiledScript, environment)
+                }
+            }
+        }
+}

libraries/scripting/common/src/kotlin/script/experimental/host/scriptHostUtil.kt

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package kotlin.script.experimental.host
+
+import kotlin.script.experimental.api.ScriptSource
+import kotlin.script.experimental.api.ScriptSourceFragments
+import kotlin.script.experimental.api.ScriptSourceNamedFragment
+import java.io.File
+import java.net.URL
+
+fun ScriptSourceFragments.isWholeFile(): Boolean = fragments?.isEmpty() ?: true
+
+fun ScriptSource.getScriptText(): String = when {
+    text != null -> text!!
+    location != null ->
+        location!!.openStream().bufferedReader().readText()
+    else -> throw RuntimeException("unable to get text from null script")
+}
+
+fun ScriptSourceFragments.getMergedScriptText(): String {
+    val originalScriptText = originalSource.getScriptText()
+    return if (isWholeFile()) {
+        originalScriptText
+    } else {
+        val sb = StringBuilder(originalScriptText.length)
+        var prevFragment: ScriptSourceNamedFragment? = null
+        for (fragment in fragments!!) {
+            val fragmentStartPos = fragment.range.start.absolutePos
+            val fragmentEndPos = fragment.range.end.absolutePos
+            if (fragmentStartPos == null || fragmentEndPos == null)
+                throw RuntimeException("Script fragments require absolute positions (received: $fragment)")
+            val curPos = if (prevFragment == null) 0 else prevFragment.range.end.absolutePos!!
+            if (prevFragment != null && prevFragment.range.end.absolutePos!! > fragmentStartPos) throw RuntimeException("Unsorted or overlapping fragments: previous: $prevFragment, current: $fragment")
+            if (curPos < fragmentStartPos) {
+                sb.append(
+                    originalScriptText.subSequence(
+                        curPos,
+                        fragmentStartPos
+                    ).map { if (it == '\r' || it == '\n') it else ' ' }) // preserving lines layout
+            }
+            sb.append(originalScriptText.subSequence(fragmentStartPos, fragmentEndPos))
+            prevFragment = fragment
+        }
+        sb.toString()
+    }
+}
+
+open class FileScriptSource(val file: File) : ScriptSource {
+    override val location: URL? get() = file.toURI().toURL()
+    override val text: String? get() = null
+}
+
+fun File.toScriptSource(): ScriptSource = FileScriptSource(this)
+
+open class StringScriptSource(val source: String) : ScriptSource {
+    override val location: URL? get() = null
+    override val text: String? get() = source
+}
+
+fun String.toScriptSource(): ScriptSource = StringScriptSource(this)