Remove data race in IsRunning method

This commit locks the job struct when reading or writting to the
isRunning boolean.

Also this adds -race to the travis check so this doesn't happen
again in the future.

Fixes #4

Author: carlescere

.travis.yml

@@ -11,4 +11,4 @@ install:
   - if ! go get code.google.com/p/go.tools/cmd/cover; then go get golang.org/x/tools/cmd/cover; fi
   - go get github.com/stretchr/testify/assert
 script:
-  - $HOME/gopath/bin/goveralls -service=travis-ci -repotoken $COVERALLS_TOKEN
+  - $HOME/gopath/bin/goveralls -race -service=travis-ci -repotoken $COVERALLS_TOKEN

scheduler.go

@@ -18,6 +18,7 @@ import (
 	"errors"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 )
 
@@ -33,6 +34,7 @@ type Job struct {
 	err       error
 	schedule  scheduled
 	isRunning bool
+	sync.RWMutex
 }
 
 type recurrent struct {
@@ -175,24 +177,32 @@ func (j *Job) Run(f func()) (*Job, error) {
 			case <-j.Quit:
 				return
 			case <-j.SkipWait:
-				go func(j *Job) {
-					j.isRunning = true
-					j.fn()
-					j.isRunning = false
-				}(j)
+				go runJob(j)
 			case <-time.After(next):
-				go func(j *Job) {
-					j.isRunning = true
-					j.fn()
-					j.isRunning = false
-				}(j)
+				go runJob(j)
 			}
 			next, _ = j.schedule.nextRun()
 		}
 	}(j)
 	return j, nil
 }
 
+func (j *Job) setRunning(running bool) {
+	j.Lock()
+	defer j.Unlock()
+
+	j.isRunning = running
+}
+
+func runJob(job *Job) {
+	if job.IsRunning() {
+		return
+	}
+	job.setRunning(true)
+	job.fn()
+	job.setRunning(false)
+}
+
 func parseTime(str string) (hour, min, sec int, err error) {
 	chunks := strings.Split(str, ":")
 	var hourStr, minStr, secStr string
@@ -311,5 +321,7 @@ func (j *Job) Hours() *Job {
 
 // IsRunning returns if the job is currently running
 func (j *Job) IsRunning() bool {
+	j.RLock()
+	defer j.RUnlock()
 	return j.isRunning
 }

scheduler_test.go

@@ -20,22 +20,13 @@ func TestIsRunning(t *testing.T) {
 	assert.Nil(t, err)
 	assert.NotNil(t, job)
 
-	var i int
-
-FOR:
-	for {
-		time.Sleep(20 * time.Millisecond)
-		i++
-
-		switch i {
-		case 1:
-			assert.Equal(t, true, job.IsRunning())
+	time.Sleep(20 * time.Millisecond)
+	assert.Equal(t, true, job.IsRunning())
+	job.SkipWait <- true
+	assert.Equal(t, true, job.IsRunning())
 
-		case 2:
-			assert.Equal(t, false, job.IsRunning())
-			break FOR
-		}
-	}
+	time.Sleep(20 * time.Millisecond)
+	assert.Equal(t, false, job.IsRunning())
 }
 
 func TestExecution(t *testing.T) {