Added a -version option to the compiler

compiler/cli/src/org/jetbrains/jet/cli/CompilerArguments.java

@@ -59,6 +59,9 @@ public class CompilerArguments {
     @Argument(value = "verbose", description = "Enable verbose logging output")
     public boolean verbose;
 
+    @Argument(value = "version", description = "Display compiler version")
+    public boolean version;
+
 
     public String getClasspath() {
         return classpath;

compiler/cli/src/org/jetbrains/jet/cli/CompilerVersion.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2010-2012 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.jet.cli;
+
+/**
+ * @author abreslav
+ */
+public class CompilerVersion {
+    // The value of this constant is generated by the build script
+    // DON'T MODIFY IT
+    public static final String VERSION = "@snapshot@";
+}

compiler/cli/src/org/jetbrains/jet/cli/KotlinCompiler.java

@@ -20,6 +20,7 @@ import com.sampullara.cli.Args;
 import org.jetbrains.jet.compiler.CompileEnvironment;
 import org.jetbrains.jet.compiler.CompileEnvironmentException;
 import org.jetbrains.jet.compiler.MessageRenderer;
+import org.jetbrains.jet.lang.diagnostics.Severity;
 
 import java.io.PrintStream;
 
@@ -91,6 +92,11 @@ public class KotlinCompiler {
         System.setProperty("java.awt.headless", "true");
 
         MessageRenderer messageRenderer = arguments.tags ? MessageRenderer.TAGS : MessageRenderer.PLAIN;
+
+        if (arguments.version) {
+            errStream.println(messageRenderer.render(Severity.INFO, "Kotlin Compiler version " + CompilerVersion.VERSION, null, -1, -1));
+        }
+
         CompileEnvironment environment = new CompileEnvironment(messageRenderer, arguments.verbose);
         try {
             configureEnvironment(environment, arguments, errStream);