fixes some signal handling

- `landing` reporter befouls the terminal up if `SIGINT` is issued
- `--exit` test used an incorrect description, and also did not reliably handle `SIGINT` when running
- `runMocha` helper returns the child process

Ref: #4198

Author: boneskull

lib/reporters/landing.js

@@ -98,6 +98,14 @@ function Landing(runner, options) {
     process.stdout.write('\n');
     self.epilogue();
   });
+
+  // if cursor is hidden when we ctrl-C, then it will remain hidden unless...
+  process.once('SIGINT', function() {
+    cursor.show();
+    process.nextTick(function() {
+      process.kill(process.pid, 'SIGINT');
+    });
+  });
 }
 
 /**

test/integration/helpers.js

@@ -33,6 +33,7 @@ module.exports = {
    * @param {string[]} args - Extra args to mocha executable
    * @param {Function} fn - Callback
    * @param {Object} [opts] - Options for `spawn()`
+   * @returns {ChildProcess} Mocha process
    */
   runMocha: function(fixturePath, args, fn, opts) {
     if (typeof args === 'function') {
@@ -46,7 +47,7 @@ module.exports = {
     path = resolveFixturePath(fixturePath);
     args = args || [];
 
-    invokeSubMocha(
+    return invokeSubMocha(
       args.concat(['-C', path]),
       function(err, res) {
         if (err) {

test/integration/options/exit.spec.js

@@ -1,21 +1,36 @@
 'use strict';
 
-var helpers = require('../helpers');
-var runMochaJSON = helpers.runMochaJSON;
+var runMocha = require('../helpers').runMocha;
 
 describe('--exit', function() {
   var behaviors = {
     enabled: '--exit',
     disabled: '--no-exit'
   };
 
+  // subprocess
+  var mocha;
+
+  function killSubprocess() {
+    mocha.kill('SIGKILL');
+  }
+
+  // these two handlers deal with a ctrl-c on command-line
+  before(function() {
+    process.on('SIGINT', killSubprocess);
+  });
+
+  after(function() {
+    process.removeListener('SIGINT', killSubprocess);
+  });
+
   /**
    * Returns a test that executes Mocha in a subprocess with either
    * `--exit`, `--no-exit`, or default behavior.
    *
    * @param {boolean} shouldExit - Expected result; `true` if Mocha should
    *   have force-killed the process.
-   * @param {string} [behavior] - 'enabled' or 'disabled'
+   * @param {"enabled"|"disabled"} [behavior] - 'enabled' or 'disabled'; omit for default
    * @returns {Function} async function implementing the test
    */
   var runExit = function(shouldExit, behavior) {
@@ -28,8 +43,7 @@ describe('--exit', function() {
       var timeoutObj;
       var fixture = 'exit.fixture.js';
       var args = behaviors[behavior] ? [behaviors[behavior]] : [];
-
-      var mocha = runMochaJSON(fixture, args, function postmortem(err) {
+      mocha = runMocha(fixture, args, function postmortem(err) {
         clearTimeout(timeoutObj);
         if (err) {
           return done(err);
@@ -41,15 +55,13 @@ describe('--exit', function() {
       // If this callback happens, then Mocha didn't automatically exit.
       timeoutObj = setTimeout(function() {
         didExit = false;
-        // This is the only way to kill the child, afaik.
-        // After the process ends, the callback to `run()` above is handled.
-        mocha.kill('SIGINT');
+        killSubprocess();
       }, timeout - 500);
     };
   };
 
   describe('default behavior', function() {
-    it('should force exit after root suite completion', runExit(false));
+    it('should not force exit after root suite completion', runExit(false));
   });
 
   describe('when enabled', function() {