Implement extension point for providing script templates

idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/KotlinScriptConfigurationManager.kt

@@ -83,10 +83,11 @@ class KotlinScriptConfigurationManager(
     }
 
     private fun reloadScriptDefinitions() {
-        loadScriptConfigsFromProjectRoot(File(project.basePath ?: "")).let {
+        (makeScriptDefsFromTemplateProviderExtesions(/* TODO: add logging here */) +
+         loadScriptConfigsFromProjectRoot(File(project.basePath ?: "")).map { KotlinConfigurableScriptDefinition(it, kotlinEnvVars) } +
+         makeScriptDefsFromConfigs(loadScriptDefConfigsFromProjectRoot(File(project.basePath ?: "")))).let {
             if (it.isNotEmpty()) {
-                scriptDefinitionProvider.setScriptDefinitions(
-                        it.map { KotlinConfigurableScriptDefinition(it, kotlinEnvVars) } + StandardScriptDefinition)
+                scriptDefinitionProvider.setScriptDefinitions(it + StandardScriptDefinition)
             }
         }
     }

idea/idea-core/src/org/jetbrains/kotlin/idea/core/script/gradleScriptTemplateProvider.kt

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2010-2016 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.
+ */
+
+package org.jetbrains.kotlin.idea.core.script
+
+import org.jetbrains.kotlin.script.ScriptTemplateProvider
+import java.io.File
+
+class GradleScriptTemplateProvider: ScriptTemplateProvider {
+
+    private val gradleHome = System.getProperty("idea.gradle.home")?.let { File(it) }?.let { if (it.exists()) it else null }
+
+    override val id: String = "Gradle"
+    override val version: Int = 1
+    override val isValid: Boolean = gradleHome != null
+
+    override val templateClass: String = "org.gradle.script.lang.kotlin.KotlinBuildScript"
+    override val dependenciesClasspath: Iterable<String> = listOf(File(gradleHome, "gradle_all.jar").absolutePath)
+    override val context: Any? = gradleHome
+}