Change to not use a global variable

Also, changed to also detect a test inside a hook

Author: mmorearty

lib/interfaces/bdd.js

@@ -88,14 +88,11 @@ module.exports = function bddInterface(suite) {
       }
 
       // Check for nested test registration
-      if (global._mochaExecutionState && global._mochaExecutionState.currentRunnable) {
-        var currentRunnable = global._mochaExecutionState.currentRunnable;
-        if (currentRunnable.type === 'test') {
-          throw createUnsupportedError(
-            'Nested test "' + title + '" detected inside test "' + currentRunnable.title + '". ' +
-            'Nested tests are not allowed.'
-          );
-        }
+      var currentRunnable = suite.rootSuite().currentRunnable;
+      if (currentRunnable) {
+        throw createUnsupportedError(
+          'Nested test "' + title + '" detected inside "' + currentRunnable.title + '". '
+        );
       }
 
       var test = new Test(title, fn);

lib/interfaces/tdd.js

@@ -88,14 +88,11 @@ module.exports = function (suite) {
       }
 
       // Check for nested test registration
-      if (global._mochaExecutionState && global._mochaExecutionState.currentRunnable) {
-        var currentRunnable = global._mochaExecutionState.currentRunnable;
-        if (currentRunnable.type === 'test') {
-          throw createUnsupportedError(
-            'Nested test "' + title + '" detected inside test "' + currentRunnable.title + '". ' +
-            'Nested tests are not allowed.'
-          );
-        }
+      var currentRunnable = suite.rootSuite().currentRunnable;
+      if (currentRunnable) {
+        throw createUnsupportedError(
+          'Nested test "' + title + '" detected inside "' + currentRunnable.title + '". '
+        );
       }
 
       var test = new Test(title, fn);

lib/runner.js

@@ -191,12 +191,6 @@ class Runner extends EventEmitter {
     this.total = suite.total();
     this.failures = 0;
 
-    // Initialize global execution state tracking for nested test detection
-    if (!global._mochaExecutionState) {
-      global._mochaExecutionState = {
-        currentRunnable: null
-      };
-    }
     /**
      * @type {Map<EventEmitter,Map<string,Set<EventListener>>>}
      */
@@ -207,11 +201,9 @@ class Runner extends EventEmitter {
           test.parent.tests && test.parent.tests.indexOf(test.retriedTest());
         if (idx > -1) test.parent.tests[idx] = test;
       }
+      // Clear current runnable for nested test detection when test ends
+      self.suite.rootSuite().currentRunnable = null;
       self.checkGlobals(test);
-      // Clear execution state when test ends
-      if (global._mochaExecutionState) {
-        global._mochaExecutionState.currentRunnable = null;
-      }
     });
     this.on(constants.EVENT_HOOK_END, function (hook) {
       self.checkGlobals(hook);
@@ -534,7 +526,8 @@ Runner.prototype.hook = function (name, fn) {
       return fn();
     }
     self.currentRunnable = hook;
-    global._mochaExecutionState.currentRunnable = hook;
+    // Store current runnable on root suite for nested test detection
+    self.suite.rootSuite().currentRunnable = hook;
 
     if (name === HOOK_TYPE_BEFORE_ALL) {
       hook.ctx.currentTest = hook.parent.tests[0];
@@ -847,7 +840,8 @@ Runner.prototype.runTests = function (suite, fn) {
         return hookErr(err, errSuite, false);
       }
       self.currentRunnable = self.test;
-      global._mochaExecutionState.currentRunnable = self.test;
+      // Store current runnable on root suite for nested test detection
+      self.suite.rootSuite().currentRunnable = self.test;
       self.runTest(function (err) {
         test = self.test;
         // conditional skip within it

lib/suite.js

@@ -400,6 +400,21 @@ Suite.prototype.titlePath = function () {
   return result;
 };
 
+/**
+ * Return the root suite by traversing up the parent chain.
+ *
+ * @memberof Suite
+ * @public
+ * @return {Suite}
+ */
+Suite.prototype.rootSuite = function () {
+  var suite = this;
+  while (suite.parent) {
+    suite = suite.parent;
+  }
+  return suite;
+};
+
 /**
  * Return the total number of tests.
  *

test/integration/fixtures/nested-tests/bdd-hook-nested.fixture.js

@@ -0,0 +1,15 @@
+'use strict';
+
+// BDD hook nested test fixture - should fail with nested test error
+describe('Hook Nested Test Suite', function() {
+  before(function() {
+    // This should fail due to nested test inside hook
+    it('nested test in before hook', function() {
+      // This nested test should cause an error
+    });
+  });
+
+  it('normal test', function() {
+    // This should pass if no hook error
+  });
+});

test/integration/nested-tests.spec.js

@@ -6,7 +6,7 @@ var runMocha = helpers.runMocha;
 var runMochaJSON = helpers.runMochaJSON;
 
 describe('nested test detection', function () {
-  var nestedTestErrorMessage = 'Nested tests are not allowed';
+  var nestedTestErrorMessage = 'Nested test ".*" detected inside';
 
   describe('BDD interface', function () {
     it('should fail when nested tests are detected', function (done) {
@@ -20,7 +20,7 @@ describe('nested test detection', function () {
             return done(err);
           }
           expect(res, 'to have failed with output', new RegExp(nestedTestErrorMessage));
-          expect(res, 'to have failed with output', /inner nested test.*detected inside test.*outer test/);
+          expect(res, 'to have failed with output', /inner nested test.*detected inside.*outer test/);
           done();
         },
         spawnOpts
@@ -53,7 +53,7 @@ describe('nested test detection', function () {
             return done(err);
           }
           expect(res, 'to have failed with output', new RegExp(nestedTestErrorMessage));
-          expect(res, 'to have failed with output', /inner nested test.*detected inside test.*outer test/);
+          expect(res, 'to have failed with output', /inner nested test.*detected inside.*outer test/);
           done();
         },
         spawnOpts
@@ -86,7 +86,7 @@ describe('nested test detection', function () {
             return done(err);
           }
           expect(res, 'to have failed with output', new RegExp(nestedTestErrorMessage));
-          expect(res, 'to have failed with output', /nested in sync.*detected inside test.*sync nested test/);
+          expect(res, 'to have failed with output', /nested in sync.*detected inside.*sync nested test/);
           done();
         },
         spawnOpts
@@ -104,7 +104,7 @@ describe('nested test detection', function () {
             return done(err);
           }
           expect(res, 'to have failed with output', new RegExp(nestedTestErrorMessage));
-          expect(res, 'to have failed with output', /nested in async.*detected inside test.*async\/await nested test/);
+          expect(res, 'to have failed with output', /nested in async.*detected inside.*async\/await nested test/);
           done();
         },
         spawnOpts
@@ -122,7 +122,7 @@ describe('nested test detection', function () {
             return done(err);
           }
           expect(res, 'to have failed with output', new RegExp(nestedTestErrorMessage));
-          expect(res, 'to have failed with output', /Uncaught.*nested in callback.*detected inside test.*callback nested test/);
+          expect(res, 'to have failed with output', /Uncaught.*nested in callback.*detected inside.*callback nested test/);
           done();
         },
         spawnOpts
@@ -140,7 +140,27 @@ describe('nested test detection', function () {
             return done(err);
           }
           expect(res, 'to have failed with output', new RegExp(nestedTestErrorMessage));
-          expect(res, 'to have failed with output', /Uncaught.*nested in promise.*detected inside test.*promise nested test/);
+          expect(res, 'to have failed with output', /Uncaught.*nested in promise.*detected inside.*promise nested test/);
+          done();
+        },
+        spawnOpts
+      );
+    });
+  });
+
+  describe('hook nested tests', function () {
+    it('should fail when nested tests are detected inside hooks', function (done) {
+      var fixture = path.join('nested-tests', 'bdd-hook-nested');
+      var spawnOpts = {stdio: 'pipe'};
+      runMocha(
+        fixture,
+        ['--ui', 'bdd'],
+        function (err, res) {
+          if (err) {
+            return done(err);
+          }
+          expect(res, 'to have failed with output', new RegExp(nestedTestErrorMessage));
+          expect(res, 'to have failed with output', /nested test in before hook.*detected inside.*"before all" hook/);
           done();
         },
         spawnOpts
@@ -160,7 +180,7 @@ describe('nested test detection', function () {
             return done(err);
           }
           expect(res, 'to have failed with output', /Error: Nested test "inner nested test"/);
-          expect(res, 'to have failed with output', /detected inside test "outer test with nested test"/);
+          expect(res, 'to have failed with output', /detected inside "outer test with nested test"/);
           expect(res, 'to have failed with output', /createUnsupportedError/);
           done();
         },