feat(runner): fix '.only()' exclusive feature, mochajs#1481

This PR fix mochajs#1481, and also extends the .only() behaviour.
(i.e: it's not use grep anymore, support suite, test-case or both, add
the ability to run multiple .only)

Makefile

@@ -35,7 +35,7 @@ lint:
 
 test: lint test-unit
 
-test-all: lint test-bdd test-tdd test-qunit test-exports test-unit test-integration test-jsapi test-compilers test-glob test-requires test-reporters test-only
+test-all: lint test-bdd test-tdd test-qunit test-exports test-unit test-integration test-jsapi test-compilers test-glob test-requires test-reporters test-only test-global-only
 
 test-jsapi:
 	@node test/jsapi
@@ -117,6 +117,22 @@ test-only:
 		--ui qunit \
 		test/acceptance/misc/only/qunit
 
+test-global-only:
+	@./bin/mocha \
+		--reporter $(REPORTER) \
+		--ui tdd \
+		test/acceptance/misc/only/global/tdd
+
+	@./bin/mocha \
+		--reporter $(REPORTER) \
+		--ui bdd \
+		test/acceptance/misc/only/global/bdd
+
+	@./bin/mocha \
+		--reporter $(REPORTER) \
+		--ui qunit \
+		test/acceptance/misc/only/global/qunit
+
 test-mocha:
 	@./bin/mocha \
 		--reporter $(REPORTER) \

lib/interfaces/bdd.js

@@ -4,7 +4,6 @@
 
 var Suite = require('../suite');
 var Test = require('../test');
-var escapeRe = require('escape-string-regexp');
 
 /**
  * BDD-style interface:
@@ -27,7 +26,7 @@ module.exports = function(suite) {
   var suites = [suite];
 
   suite.on('pre-require', function(context, file, mocha) {
-    var common = require('./common')(suites, context);
+    var common = require('./common')(suites, context, mocha);
 
     context.before = common.before;
     context.after = common.after;
@@ -66,9 +65,7 @@ module.exports = function(suite) {
      */
 
     context.describe.only = function(title, fn) {
-      var suite = context.describe(title, fn);
-      mocha.grep(suite.fullTitle());
-      return suite;
+      return common.suite.only(mocha, context.describe(title, fn));
     };
 
     /**
@@ -93,10 +90,7 @@ module.exports = function(suite) {
      */
 
     context.it.only = function(title, fn) {
-      var test = context.it(title, fn);
-      var reString = '^' + escapeRe(test.fullTitle()) + '$';
-      mocha.grep(new RegExp(reString));
-      return test;
+      return common.test.only(mocha, context.it(title, fn));
     };
 
     /**

lib/interfaces/common.js

@@ -62,7 +62,38 @@ module.exports = function(suites, context) {
       suites[0].afterEach(name, fn);
     },
 
+    suite: {
+      /**
+       * Exclusive suite.
+       *
+       * @param {Object} mocha
+       * @param {Function} suite
+       */
+
+      only: function(mocha, suite) {
+        suite.isOnly = true;
+        mocha.options.hasOnly = true;
+        return suite;
+      }
+    },
+
     test: {
+
+      /**
+       * Exclusive test-case.
+       *
+       * @param {Object} mocha
+       * @param {Function} test
+       * @returns {*}
+       */
+      only: function(mocha, test) {
+        var suite = test.parent;
+        suite.isOnly = true;
+        suite.onlyTests = (suite.onlyTests || []).concat(test);
+        mocha.options.hasOnly = true;
+        return test;
+      },
+
       /**
        * Pending test case.
        *

lib/interfaces/qunit.js

@@ -4,7 +4,6 @@
 
 var Suite = require('../suite');
 var Test = require('../test');
-var escapeRe = require('escape-string-regexp');
 
 /**
  * QUnit-style interface:
@@ -61,8 +60,7 @@ module.exports = function(suite) {
      */
 
     context.suite.only = function(title, fn) {
-      var suite = context.suite(title, fn);
-      mocha.grep(suite.fullTitle());
+      return common.suite.only(mocha, context.suite(title, fn));
     };
 
     /**
@@ -83,9 +81,7 @@ module.exports = function(suite) {
      */
 
     context.test.only = function(title, fn) {
-      var test = context.test(title, fn);
-      var reString = '^' + escapeRe(test.fullTitle()) + '$';
-      mocha.grep(new RegExp(reString));
+      return common.test.only(mocha, context.test(title, fn));
     };
 
     context.test.skip = common.test.skip;

lib/interfaces/tdd.js

@@ -4,7 +4,6 @@
 
 var Suite = require('../suite');
 var Test = require('../test');
-var escapeRe = require('escape-string-regexp');
 
 /**
  * TDD-style interface:
@@ -71,8 +70,7 @@ module.exports = function(suite) {
      * Exclusive test-case.
      */
     context.suite.only = function(title, fn) {
-      var suite = context.suite(title, fn);
-      mocha.grep(suite.fullTitle());
+      return common.suite.only(mocha, context.suite(title, fn));
     };
 
     /**
@@ -95,9 +93,7 @@ module.exports = function(suite) {
      */
 
     context.test.only = function(title, fn) {
-      var test = context.test(title, fn);
-      var reString = '^' + escapeRe(test.fullTitle()) + '$';
-      mocha.grep(new RegExp(reString));
+      return common.test.only(mocha, context.test(title, fn));
     };
 
     context.test.skip = common.test.skip;

lib/mocha.js

@@ -433,6 +433,7 @@ Mocha.prototype.run = function(fn) {
   var reporter = new this._reporter(runner, options);
   runner.ignoreLeaks = options.ignoreLeaks !== false;
   runner.fullStackTrace = options.fullStackTrace;
+  runner.hasOnly = options.hasOnly;
   runner.asyncOnly = options.asyncOnly;
   if (options.grep) {
     runner.grep(options.grep, options.invert);

lib/runner.js

@@ -635,6 +635,11 @@ Runner.prototype.run = function(fn) {
   var self = this;
   var rootSuite = this.suite;
 
+  // If there is an `only` filter
+  if (this.hasOnly) {
+    filterOnly(rootSuite);
+  }
+
   fn = fn || function() {};
 
   function uncaught(err) {
@@ -686,6 +691,26 @@ Runner.prototype.abort = function() {
   return this;
 };
 
+/**
+ * Filter suites based on `isOnly` logic.
+ *
+ * @param {Array} suite
+ * @returns {Boolean}
+ * @api private
+ */
+function filterOnly(suite) {
+  // If it has `only` tests, run only those
+  if (suite.onlyTests) {
+    suite.tests = suite.onlyTests;
+  }
+  // Filter the nested suites
+  suite.suites = filter(suite.suites, filterOnly);
+  // Don't run tests from suites that are not marked as `only`
+  suite.tests = suite.isOnly ? suite.tests : [];
+  // Keep the suite only if there is something to run
+  return suite.suites.length || suite.tests.length;
+}
+
 /**
  * Filter leaks with the given globals flagged as `ok`.
  *

test/acceptance/misc/only/bdd.js

@@ -1,14 +1,125 @@
 describe('should only run .only test in this bdd suite', function() {
   it('should not run this test', function() {
-    var zero = 0;
-    zero.should.equal(1, 'this test should have been skipped');
+    (0).should.equal(1, 'this test should have been skipped');
   });
-  it.only('should run this test', function() {
-    var zero = 0;
-    zero.should.equal(0, 'this .only test should run');
+  it.only('should run this test', function() {
+    (0).should.equal(0, 'this .only test should run');
   });
   it('should run this test, not (includes the title of the .only test)', function() {
-    var zero = 0;
-    zero.should.equal(1, 'this test should have been skipped');
+    (0).should.equal(1, 'this test should have been skipped');
   });
 });
+
+describe('should not run this suite', function() {
+  it('should not run this test', function() {
+    (true).should.equal(false);
+  });
+
+  it('should not run this test', function() {
+    (true).should.equal(false);
+  });
+
+  it('should not run this test', function() {
+    (true).should.equal(false);
+  });
+});
+
+describe.only('should run all tests in this bdd suite', function() {
+  it('should run this test #1', function() {
+    (true).should.equal(true);
+  });
+
+  it('should run this test #2', function() {
+    (1).should.equal(1);
+  });
+
+  it('should run this test #3', function() {
+    ('foo').should.equal('foo');
+  });
+});
+
+describe('should run only suites that marked as `only`', function() {
+  describe.only('should run all this tdd suite', function() {
+    it('should run this test #1', function() {
+      (true).should.equal(true);
+    });
+
+    it('should run this test #2', function() {
+      (true).should.equal(true);
+    });
+  });
+
+  describe('should not run this suite', function() {
+    it('should run this test', function() {
+      (true).should.equal(false);
+    });
+  });
+});
+
+// Nested situation
+describe('should not run parent tests', function() {
+  it('should not run this test', function() {
+    (true).should.equal(false);
+  });
+  describe('and not the child tests too', function() {
+    it('should not run this test', function() {
+      (true).should.equal(false);
+    });
+    describe.only('but run all the tests in this suite', function() {
+      it('should run this test #1', function() {
+        (true).should.equal(true);
+      });
+      it('should run this test #2', function() {
+        (true).should.equal(true);
+      });
+    });
+  });
+});
+
+// mark test as `only` override the suite behavior
+describe.only('should run only tests that marked as `only`', function() {
+  it('should not run this test #1', function() {
+    (false).should.equal(true);
+  });
+
+  it.only('should run this test #2', function() {
+    (true).should.equal(true);
+  });
+
+  it('should not run this test #3', function() {
+    (false).should.equal(true);
+  });
+
+  it.only('should run this test #4', function() {
+    (true).should.equal(true);
+  });
+});
+
+describe.only('Should run only test cases that mark as only', function() {
+  it.only('should runt his test', function() {
+    (true).should.equal(true);
+  });
+
+  it('should not run this test', function() {
+    (false).should.equal(true);
+  });
+
+  describe('should not run this suite', function() {
+    it('should not run this test', function() {
+      (false).should.equal(true);
+    });
+  });
+});
+
+// Root Suite
+it.only('#Root-Suite, should run this test-case #1', function() {
+  (true).should.equal(true);
+});
+
+it.only('#Root-Suite, should run this test-case #2', function() {
+  (true).should.equal(true);
+});
+
+it('#Root-Suite, should not run this test', function() {
+  (false).should.equal(true);
+});

test/acceptance/misc/only/global/bdd.js

@@ -0,0 +1,12 @@
+// Root-only test cases
+it.only('#Root-Suite, should run this bdd test-case #1', function() {
+  (true).should.equal(true);
+});
+
+it('#Root-Suite, should not run this bdd test-case #2', function() {
+  (false).should.equal(true);
+});
+
+it('#Root-Suite, should not run this bdd test-case #3', function() {
+  (false).should.equal(true);
+});

test/acceptance/misc/only/global/qunit.js

@@ -0,0 +1,12 @@
+// Root-only test cases
+test.only('#Root-Suite, should run this qunit test-case #1', function() {
+  (true).should.equal(true);
+});
+
+test('#Root-Suite, should not run this qunit test-case #2', function() {
+  (false).should.equal(true);
+});
+
+test('#Root-Suite, should not run this qunit test-case #3', function() {
+  (false).should.equal(true);
+});

test/acceptance/misc/only/global/tdd.js

@@ -0,0 +1,12 @@
+// Root-only test cases
+test.only('#Root-Suite, should run this tdd test-case #1', function() {
+  (true).should.equal(true);
+});
+
+test('#Root-Suite, should not run this tdd test-case #2', function() {
+  (false).should.equal(true);
+});
+
+test('#Root-Suite, should not run this tdd test-case #3', function() {
+  (false).should.equal(true);
+});