Support -w, --watch and --watch-extensions args

README.md

@@ -56,6 +56,7 @@ Usage: electron-mocha [options] [files]
     -s, --slow <ms>        "slow" test threshold in milliseconds [75]
     -t, --timeout <ms>     set test-case timeout in milliseconds [2000]
     -u, --ui <name>        specify user-interface (bdd|tdd|exports)
+    -w, --watch            watch files for changes
     --check-leaks          check for global variable leaks
     --compilers            use the given module(s) to compile files
     --globals <names>      allow the given comma-delimited global [names]
@@ -64,6 +65,7 @@ Usage: electron-mocha [options] [files]
     --no-timeouts          disables timeouts
     --recursive            include sub directories
     --renderer             run tests in renderer process
+    --watch-extensions     additional extensions to monitor with --watch
 
 ```
 

args.js

@@ -19,6 +19,7 @@ function parse (argv) {
     .option('-s, --slow <ms>', '"slow" test threshold in milliseconds [75]')
     .option('-t, --timeout <ms>', 'set test-case timeout in milliseconds [2000]')
     .option('-u, --ui <name>', 'specify user-interface (bdd|tdd|exports)', 'bdd')
+    .option('-w, --watch', 'watch files for changes')
     .option('--check-leaks', 'check for global variable leaks')
     .option('--compilers <ext>:<module>,...', 'use the given module(s) to compile files', list, [])
     .option('--globals <names>', 'allow the given comma-delimited global [names]', list, [])
@@ -27,6 +28,7 @@ function parse (argv) {
     .option('--no-timeouts', 'disables timeouts')
     .option('--recursive', 'include sub directories')
     .option('--renderer', 'run tests in renderer process')
+    .option('--watch-extensions <ext>,...', 'additional extensions to monitor with --watch')
 
   program.on('globals', function (val) {
     globals = globals.concat(list(val))

mocha.js

@@ -42,6 +42,12 @@ function createFromArgs (args) {
     extensions.push(ext)
   })
 
+  if (args.watch) {
+    args.watchExtensions = args.watchExtensions ?
+      args.watchExtensions.split(',') : []
+    args.watchExtensions = args.watchExtensions.concat(extensions)
+  }
+
   files = files.map(function (f) {
     return path.resolve(f)
   })
@@ -55,10 +61,65 @@ function createFromArgs (args) {
   return mocha
 }
 
+function watch (mocha, args, callback) {
+  var utils = Mocha.utils
+  var runner
+  process.on('SIGINT', function(){
+    callback(0)
+  })
+
+  var watchFiles = utils.files(process.cwd(), [ 'js' ].concat(args.watchExtensions))
+  var runAgain = false
+
+  function loadAndRun () {
+    try {
+      runAgain = false
+      runner = mocha.run(function () {
+        runner = null
+        if (runAgain) {
+          rerun()
+        }
+      })
+    } catch(e) {
+      console.log(e.stack)
+    }
+  }
+
+  function purge () {
+    watchFiles.forEach(function (file) {
+      delete require.cache[file]
+    })
+  }
+
+  loadAndRun()
+
+  function rerun () {
+    purge()
+    if (!args.grep) mocha.grep(null)
+    mocha.suite = mocha.suite.clone()
+    mocha.suite.ctx = new Mocha.Context
+    mocha.ui(args.ui)
+    loadAndRun()
+  }
+
+  utils.watch(watchFiles, function () {
+    runAgain = true
+    if (runner) {
+      runner.abort()
+    } else {
+      rerun()
+    }
+  })
+}
+
 function run (args, callback) {
-  var mocha = createFromArgs(args)
-  /* var runner = */ mocha.run(callback)
-  // process.on('SIGINT', function () { runner.abort() })
+  var mocha = createFromArgs(args, callback)
+  if (args.watch) {
+    watch(mocha, args, callback)
+  } else {
+    /* var runner = */ mocha.run(callback)
+    // process.on('SIGINT', function () { runner.abort() })
+  }
 }
 
 module.exports = {

renderer/run.js

@@ -9,6 +9,7 @@ var mocha = require('../mocha')
 }*/
 
 // console.log(JSON.stringify(window.__args__, null, 2))
-mocha.run(window.__args__, function (failureCount) {
+var args = JSON.parse(JSON.stringify(window.__args__))
+mocha.run(args, function (failureCount) {
   ipc.send('mocha-done', failureCount)
 })