Support for wtfnode

bin/_mocha

@@ -7,9 +7,12 @@
  * Module dependencies.
  */
 
+const wtfnode = require('wtfnode');
+
 const program = require('commander');
 const path = require('path');
 const fs = require('fs');
+const ms = require('ms');
 const minimatch = require('minimatch');
 const resolve = path.resolve;
 const exists = fs.existsSync;
@@ -31,6 +34,18 @@ const setInterval = global.setInterval;
 const clearTimeout = global.clearTimeout;
 const clearInterval = global.clearInterval;
 
+function calcLeakTimeout() {
+  if (program.leakTimeout) {
+    if (typeof program.leakTimeout === 'string') {
+      return ms(program.leakTimeout);
+    } else {
+      return program.leakTimeout;
+    }
+  } else {
+    return 60000;
+  }
+}
+
 /**
  * Exits Mocha when tests + code under test has finished execution (default)
  * @param {number} code - Exit code; typically # of failures
@@ -39,6 +54,30 @@ const exitLater = code => {
   process.on('exit', () => {
     process.exit(Math.min(code, 255));
   });
+
+  let timeout = Date.now() + calcLeakTimeout();
+  let timer = setInterval(() => {
+    if (Date.now() > timeout) {
+      clearInterval(timer);
+
+      console.error(
+        'Process did not terminate, dumping remaining handles and exiting'
+      );
+      wtfnode.dump();
+
+      process.removeAllListeners('exit');
+      process.exit(-1);
+    } else {
+      let activeHandles = process
+        ._getActiveHandles()
+        .filter(h => typeof h.fd !== 'number' || h.fd > 2); // Filter out stdio handles
+
+      // Allow this timer to be running
+      if (activeHandles.length <= 1) {
+        clearInterval(timer);
+      }
+    }
+  }, 10);
 };
 
 /**
@@ -258,7 +297,11 @@ program
     '--cleanup-after <timeout>',
     'Always run after hooks even if the process is killed'
   )
-  .option('--repeat <n>', 'Repeat all tests n times');
+  .option('--repeat <n>', 'Repeat all tests n times')
+  .option(
+    '--leak-timeout <ms>',
+    'Kill process forcefully if not terminated after the last test has completed'
+  );
 
 program._name = 'mocha';
 

package.json

@@ -470,7 +470,8 @@
     "he": "1.1.1",
     "minimatch": "3.0.4",
     "mkdirp": "0.5.1",
-    "supports-color": "5.4.0"
+    "supports-color": "5.4.0",
+    "wtfnode": "^0.8.0"
   },
   "devDependencies": {
     "@mocha/docdash": "^1.0.1",

test/integration/fixtures/hang-after-completion.fixture.js

@@ -0,0 +1,12 @@
+'use strict';
+
+describe('hanging test', function () {
+    this.timeout(3000);
+
+    it('should complete with a hanging timer', function() {
+        console.log('it()');
+        setTimeout(function () {
+            console.log('timer expired');
+        }, 300);
+    });
+});

test/integration/options.spec.js

@@ -779,6 +779,60 @@ describe('options', function() {
       });
     });
   });
+
+  describe('--leak-timeout', function() {
+    function run(fixture, args, fn) {
+      helpers.runMocha(fixture, ['--reporter', 'dot'].concat(args), function(
+        err,
+        res
+      ) {
+        if (err) {
+          fn(err);
+        } else {
+          fn(null, res.code, res.output);
+        }
+      });
+    }
+
+    it('should give the program time to complete', function(done) {
+      run(
+        'hang-after-completion.fixture.js',
+        ['--leak-timeout', '500'],
+        function(err, code, output) {
+          if (err) {
+            done(err);
+          } else {
+            assert.equal(code, 0);
+            assert(/it\(\)\n/.test(output));
+            assert(/timer expired\n/.test(output));
+            assert(!/Process did not terminate\n/.test(output));
+            done();
+          }
+        }
+      );
+    });
+
+    it('should forcefully kill the program', function(done) {
+      run(
+        'hang-after-completion.fixture.js',
+        ['--leak-timeout', '100'],
+        function(err, code, output) {
+          if (err) {
+            done(err);
+          } else {
+            assert.equal(code, 255);
+            assert(/it\(\)\n/.test(output));
+            assert(!/timer expired\n/.test(output));
+            assert(/Process did not terminate/.test(output));
+            assert(
+              /fixtures\/hang-after-completion\.fixture\.js:8\n/.test(output)
+            );
+            done();
+          }
+        }
+      );
+    });
+  });
 });
 
 function onlyConsoleOutput() {