Create a new class for commands to extend from that includes utilities that scripts do

Author: jameskleeh

grails-bootstrap/build.gradle

@@ -2,6 +2,7 @@ import org.apache.tools.ant.filters.ReplaceTokens
 
 dependencies {
     compile ( "org.codehaus.groovy:groovy-xml:$groovyVersion" )
+    compile ( "org.codehaus.groovy:groovy-templates:$groovyVersion" )
     compile "org.yaml:snakeyaml:1.14"
 
     compileOnly("org.fusesource.jansi:jansi:$jansiVersion")

grails-core/src/main/groovy/grails/dev/commands/GrailsApplicationCommand.groovy

@@ -0,0 +1,28 @@
+package grails.dev.commands
+
+import grails.codegen.model.ModelBuilder
+import grails.dev.commands.io.FileSystemInteraction
+import grails.dev.commands.io.FileSystemInteractionImpl
+import grails.dev.commands.template.TemplateRenderer
+import grails.dev.commands.template.TemplateRendererImpl
+
+
+trait GrailsApplicationCommand implements ApplicationCommand, ModelBuilder {
+
+    @Delegate TemplateRenderer templateRenderer
+    @Delegate FileSystemInteraction fileSystemInteraction
+    ExecutionContext executionContext
+
+    boolean handle(ExecutionContext executionContext) {
+        this.executionContext = executionContext
+        this.templateRenderer = new TemplateRendererImpl(executionContext.baseDir)
+        this.fileSystemInteraction = new FileSystemInteractionImpl(executionContext.baseDir)
+        handle()
+    }
+
+    List<String> getArgs() {
+        executionContext.commandLine.remainingArgs
+    }
+
+    abstract boolean handle()
+}

grails-core/src/main/groovy/grails/dev/commands/io/FileSystemInteraction.groovy

@@ -0,0 +1,142 @@
+/*
+ * Copyright 2014 original authors
+ *
+ * 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 grails.dev.commands.io
+
+import org.grails.io.support.Resource
+
+
+/**
+ * Utility methods exposed to scripts for interacting with resources (found on the file system or jars) and the file system
+ *
+ * @author Graeme Rocher
+ * @since 3.0
+ */
+interface FileSystemInteraction {
+
+    /**
+     * Makes a directory
+     *
+     * @param path The path to the directory
+     */
+    FileSystemInteraction mkdir(path)
+    /**
+     * Deletes a file
+     *
+     * @param path The path to the file
+     */
+    FileSystemInteraction delete(path)
+    /**
+     * Allows Gradle style simple copy specs
+     *
+     * @param callable The callable
+     * @return this
+     */
+    FileSystemInteraction copy(@DelegatesTo(CopySpec) Closure callable)
+    /**
+     * Copies a resource to the target destination
+     *
+     * @param path The path
+     * @param destination The destination
+     */
+    FileSystemInteraction copy(path, destination)
+    /**
+     * Copies resources to the target destination
+     *
+     * @param path The path
+     * @param destination The destination
+     */
+    FileSystemInteraction copyAll(Iterable resources, destination)
+    /**
+     * Copy a Resource from the given location to the given directory or location
+     *
+     * @param from The resource to copy
+     * @param to The location to copy to
+     * @return The {@FileSystemInteraction} instance
+     */
+    FileSystemInteraction copy(Resource from, File to)
+    /**
+     * Obtain a file for the given path
+     *
+     * @param path The path
+     * @return The file
+     */
+    File file(Object path)
+    /**
+     * @return The target build directory
+     */
+    File getBuildDir()
+    /**
+     * @return The directory where resources are processed to
+     */
+    File getResourcesDir()
+    /**
+     * @return The directory where classes are compiled to
+     */
+    File getClassesDir()
+    /**
+     * Finds a source file for the given class name
+     * @param className The class name
+     * @return The source resource
+     */
+    Resource source(String className)
+    /**
+     * Obtain a resource for the given path
+     * @param path The path
+     * @return The resource
+     */
+    Resource resource(Object path)
+    /**
+     * Obtain resources for the given pattern
+     *
+     * @param pattern The pattern
+     * @return The resources
+     */
+    Collection<Resource> resources(String pattern)
+    /**
+     * Obtain the path of the resource relative to the current project
+     *
+     * @param path The path to inspect
+     * @return The relative path
+     */
+    String projectPath(Object path)
+
+    /**
+     * The class name of the given resource
+     *
+     * @param resource The resource
+     * @return The class name
+     */
+    String className(Resource resource)
+    
+    /**
+     * Get files matching the given pattern
+     *
+     * @param pattern The pattern
+     * @return the files
+     */
+    Collection<File> files(String pattern)
+
+    static class CopySpec {
+        def from
+        def into
+        void from(path) {
+            this.from = path
+        }
+        void into(path) {
+            this.into = path
+        }
+    }
+}