Do not silently fail at syntax error

Fixes #15
Closes #16

tasks/jscs.js

@@ -17,7 +17,7 @@ module.exports = function( grunt ) {
                 return jscs.check( path );
             });
 
-        Vow.all( checks ).then(function( results ) {
+        Vow.any( checks ).then(function( results ) {
             jscs.setErrors( concat.apply( [], results ) ).report().notify();
 
             done( options.force ? true : !jscs.count() );

tasks/lib/jscs.js

@@ -60,7 +60,13 @@ exports.init = function( grunt ) {
      * @see Checker#checkPath
      */
     JSCS.prototype.check = function( path ) {
-        return this.checker.checkPath( path );
+        var checkPath = this.checker.checkPath( path );
+
+        checkPath.fail(function( error ) {
+            grunt.warn( error );
+        });
+
+        return checkPath;
     }
 
     /**

test/enmasse.js

@@ -15,6 +15,17 @@ exports.fail = function( test ) {
     });
 };
 
+exports.fail = function( test ) {
+    grunt.util.spawn({
+        cmd: "grunt",
+        args: [ "jscs:broken" ]
+    }, function( error, result ) {
+        test.equal( grunt.file.read( "expectations/broken" ), result.stdout );
+
+        test.done();
+    });
+};
+
 exports.force = function( test ) {
     grunt.util.spawn({
         cmd: "grunt",

test/enmasse/Gruntfile.js

@@ -11,6 +11,15 @@ module.exports = function( grunt ) {
                     config: "../configs/fail.json"
                 }
             },
+            broken: {
+                files: {
+                    src: [ "../fixtures/broken.js", "../fixtures/fixture.js" ]
+                },
+                options: {
+                    config: "../configs/fail.json",
+                    force: true
+                }
+            },
             force: {
                 files: {
                     src: "../fixtures/fixture.js"

test/enmasse/expectations/broken

@@ -0,0 +1,4 @@
+Running "jscs:broken" (jscs) task
+Warning: Syntax error at ../fixtures/broken.js: Line 3: Unexpected end of input Use --force to continue.
+
+Aborted due to warnings.

test/fixtures/broken.js

@@ -0,0 +1,3 @@
+( function ( global ) {
+
+'use strict';

test/methods.js

@@ -223,5 +223,24 @@ module.exports = {
 
             test.done();
         });
+    },
+
+    "Don't break on syntax error": function( test ) {
+        hooker.hook( grunt, "warn", {
+            pre: function( message ) {
+                test.ok( message.toString().length, "error message should not be empty" );
+
+                test.done();
+                return hooker.preempt();
+            },
+
+            once: true
+        });
+
+        var jscs = new JSCS({
+            "requireCurlyBraces": [ "while" ],
+        });
+
+        jscs.check( "test/fixtures/broken.js" );
     }
 };