--forbid-only and --forbid-pending now handle suites properly (#3578)

* fail-fast when .only encountered in Suite w/ --forbid-only
* fail-fast when .skip encountered in Suite w/ --forbid-pending
* move importing chai to the top of the file to avoid timeout

Signed-off-by: Outsider <outsideris@gmail.com>

lib/interfaces/common.js

@@ -12,6 +12,22 @@ var utils = require('../utils');
  * @return {Object} An object containing common functions.
  */
 module.exports = function(suites, context, mocha) {
+  /**
+   * Check if the suite should be tested.
+   *
+   * @private
+   * @param {Suite} suite - suite to check
+   * @returns {boolean}
+   */
+  function shouldBeTested(suite) {
+    return (
+      !mocha.options.grep ||
+      (mocha.options.grep &&
+        mocha.options.grep.test(suite.fullTitle()) &&
+        !mocha.options.invert)
+    );
+  }
+
   return {
     /**
      * This is only present if flag --delay is passed into Mocha. It triggers
@@ -108,8 +124,17 @@ module.exports = function(suites, context, mocha) {
         suite.file = opts.file;
         suites.unshift(suite);
         if (opts.isOnly) {
+          if (mocha.options.forbidOnly && shouldBeTested(suite)) {
+            throw new Error('`.only` forbidden');
+          }
+
           suite.parent._onlySuites = suite.parent._onlySuites.concat(suite);
         }
+        if (suite.pending) {
+          if (mocha.options.forbidPending && shouldBeTested(suite)) {
+            throw new Error('Pending test forbidden');
+          }
+        }
         if (typeof opts.fn === 'function') {
           var result = opts.fn.call(suite);
           if (typeof result !== 'undefined') {

test/integration/fixtures/options/forbid-only/only-empty-suite.js

@@ -0,0 +1,3 @@
+'use strict';
+
+describe.only('forbid only - suite marked with only', function() {});

test/integration/fixtures/options/forbid-pending/skip-empty-suite.js

@@ -0,0 +1,3 @@
+'use strict';
+
+describe.skip('forbid pending - suite marked with skip', function() {});

test/integration/helpers.js

@@ -64,7 +64,7 @@ module.exports = {
         var result = JSON.parse(res.output);
         result.code = res.code;
       } catch (err) {
-        return fn(err);
+        return fn(new Error('output is not valid JSON:\n\n' + res.output));
       }
 
       fn(null, result);