add --version to CLI

lib/tslint.d.ts

@@ -10847,6 +10847,7 @@ declare module Lint {
         private fileName;
         private source;
         private options;
+        static VERSION: string;
         constructor(fileName: string, source: string, options: any);
         public lint(): LintResult;
         private getRelativePath(directory);

src/tslint-cli.ts

@@ -21,8 +21,8 @@ var path = require("path");
 var optimist = require("optimist")
     .usage("usage: $0")
     .check((argv) => {
-        // f is required unless we're asking for help; throw an error if f is missing unless help is there
-        if (!("f" in argv) && !("help" in argv)) {
+        // at least one of file or help or version must be present
+        if (!(argv.f || argv.h || argv.v)) {
             throw "Missing required arguments: f";
         }
     })
@@ -35,6 +35,10 @@ var optimist = require("optimist")
             alias: "file",
             describe: "file to lint"
         },
+        "h": {
+            alias: "help",
+            describe: "display detailed help"
+        },
         "o": {
             alias: "out",
             describe: "output file"
@@ -52,10 +56,10 @@ var optimist = require("optimist")
             describe: "output format (prose, json, verbose)",
             default: "prose"
         },
-        "h": {
-            alias: "help",
-            describe: "display detailed help"
-        },
+        "v": {
+            alias: "version",
+            describe: "current version"
+        }
     });
 var argv = optimist.argv;
 
@@ -70,6 +74,11 @@ if (argv.o !== undefined) {
     outputStream = process.stdout;
 }
 
+if (argv.v !== undefined) {
+    outputStream.write(Lint.Linter.VERSION + "\n");
+    process.exit(0);
+}
+
 if ("help" in argv) {
     outputStream.write(optimist.help());
     var outputString = "\ntslint accepts the following commandline options:\n" +
@@ -119,6 +128,9 @@ if ("help" in argv) {
         "        and verbose. prose is the default if this option is not used. Additonal\n" +
         "        formatters can be added and used if the --formatters-dir option is set.\n" +
         "\n" +
+        "    -v, --version:\n" +
+        "        The current version of tslint.\n" +
+        "\n" +
         "    -h, --help:\n" +
         "       Prints this help message.\n";
     outputStream.write(outputString);

src/tslint.ts

@@ -42,6 +42,8 @@ module Lint {
         private source: string;
         private options: any;
 
+        public static VERSION = "0.4.2";
+
         constructor(fileName: string, source: string, options: any) {
             this.fileName = fileName;
             this.source = source;