[[fix]] case statments with no code should not increase complexity js…

…hint#840

src/jshint.js

@@ -3071,6 +3071,9 @@ var JSHINT = (function() {
     state.funct["(metrics)"].ComplexityCount += 1;
   }
 
+  function decreaseComplexityCount() {
+    state.funct["(metrics)"].ComplexityCount -= 1;
+  }
   // Parse assignments that were found instead of conditionals.
   // For example: if (a = 1) { ... }
 
@@ -4002,6 +4005,9 @@ var JSHINT = (function() {
         increaseComplexityCount();
         g = true;
         advance(":");
+        //if next token is case then we are falling through decrease complexity
+        if(state.tokens.next.type == "case")
+          decreaseComplexityCount();
         state.funct["(verb)"] = "case";
         break;
       case "default":

tests/unit/options.js

@@ -2140,6 +2140,42 @@ exports.fnmetrics = function (test) {
   test.done();
 };
 
+//switch statements with fall through cases should not increase complexity
+exports.switchcomplexity = function (test) {
+  JSHINT([
+    "function foo(a) { switch(a){ case '1': case '2': case '3': break;}  }",
+    "function bar(b) { switch(b){ case '1': case '2': break; case '3': break; }  }",
+    "function hasdefault(b) { switch(b){ case '1': case '2': break; case '3': default:break;}  }",
+    "function allbreaks(b) { switch(b){ case '1':break; case '2': break; case '3':break; default:break;}  }"
+  ]);
+
+  test.equal(JSHINT.data().functions.length, 4);
+
+  test.deepEqual(JSHINT.data().functions[0].metrics, {
+        complexity: 2,
+        parameters: 1,
+        statements: 1
+  });
+  test.deepEqual(JSHINT.data().functions[1].metrics, {
+        complexity: 3,
+        parameters: 1,
+        statements: 1
+  });
+  test.deepEqual(JSHINT.data().functions[2].metrics, {
+        complexity: 3,
+        parameters: 1,
+        statements: 1
+  });
+  test.deepEqual(JSHINT.data().functions[3].metrics, {
+        complexity: 4,
+        parameters: 1,
+        statements: 1
+  });
+
+  test.done();
+};
+
+
 /*
  * Tests ignored warnings.
  */