Ensure generated parser is re-generated during build (#12937)

Ultimately we should remove Parser.java and other generated files from
the project but this still needs tweaking ide.xml somehow so the parser
is built.

Change-Id: Iac491c6a50c87e1e8e0bb2f612e82186319a6de3

theme-compiler/apache2header.txt

@@ -0,0 +1,15 @@
+/*
+ * Copyright 2000-2013 Vaadin Ltd.
+ * 
+ * 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.
+ */

theme-compiler/build.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0"?>
 
-<project name="vaadin-theme-compiler" basedir="." default="publish-local" xmlns:ivy="antlib:org.apache.ivy.ant">
+<project name="vaadin-theme-compiler" basedir="." default="publish-local" xmlns:ivy="antlib:org.apache.ivy.ant" xmlns:antcontrib="antlib:net.sf.antcontrib">
     <description>
         Compiles build helpers used when building other modules.
     </description>
@@ -12,7 +12,10 @@
     <property name="module.name" value="vaadin-theme-compiler" />
     <property name="module.symbolic" value="com.vaadin.theme-compiler" />
     <property name="result.dir" value="result" />
-    <property name="sass.parser.jj" location="src/com/vaadin/sass/internal/parser/Parser.jj" />
+    <property name="parser.src.dir" value="src/com/vaadin/sass/internal/parser" />
+    <property name="generate.dir" value="${result.dir}/generated/${parser.src.dir}" />
+    <property name="header.file" location="apache2header.txt" />
+
     <path id="classpath.compile.custom">
     </path>
     <path id="classpath.test.custom" />
@@ -25,8 +28,27 @@
             javacc task requires the jar to be named javacc.jar -->
         <property name="javacc.home" location="${result.dir}/javacc" />
         <ivy:retrieve organisation="net.java.dev.javacc" module="javacc" revision="5.0" inline="true" type="jar" pattern="${javacc.home}/[artifact].[ext]" />
-        <javacc target="${sass.parser.jj}" javacchome="${javacc.home}">
+        <delete dir="${generate.dir}" />
+        <mkdir dir="${generate.dir}" />
+        <!-- Generate new parser files in another directory, this ensure
+        they are always generated -->
+        <copy file="${parser.src.dir}/Parser.jj" todir="${generate.dir}" />
+        <javacc target="${generate.dir}/Parser.jj" javacchome="${javacc.home}">
         </javacc>
+        <!-- Add headers to the generated files and copy back to src -->
+        <antcontrib:foreach target="prepend.generated.file.header" param="path">
+            <path>
+                <fileset dir="${generate.dir}" includes="*.java" />
+            </path>
+        </antcontrib:foreach>
+    </target>
+
+    <target name="prepend.generated.file.header">
+        <basename property="file" file="${path}" />
+        <concat destfile="${parser.src.dir}/${file}">
+            <header filtering="no" trimleading="no" file="${header.file}" />
+            <path path="${generate.dir}/${file}" />
+        </concat>
     </target>
 
     <target name="jar" depends="parser">