fix(pkg/sshd/lock_test.go): add a test for locking and unlocking repo locks many times

Author: Aaron Schlesinger

pkg/sshd/lock_test.go

@@ -1,14 +1,62 @@
 package sshd
 
 import (
+	"errors"
+	"sync"
 	"testing"
 	"time"
+
+	"github.com/arschles/assert"
 )
 
 const (
 	callbackTimeout = 1 * time.Second
 )
 
+var (
+	errWGTimedOut = errors.New("waitgroup wait timed out")
+)
+
+// waitWithTimeout waits for wg.Done() until timeout expires. returns errWGTimedOut if timeout expired before wg.Done() returned, otherwise returns nil. this func is naturally leaky if wg.Done() never returns
+func waitWithTimeout(wg *sync.WaitGroup, timeout time.Duration) error {
+	ch := make(chan struct{})
+	go func() {
+		defer close(ch)
+		wg.Wait()
+	}()
+	select {
+	case <-time.After(timeout):
+		return errWGTimedOut
+	case <-ch:
+		return nil
+	}
+}
+
+func TestMultipleSameRepoLocks(t *testing.T) {
+	var wg sync.WaitGroup
+	const repo = "repo1"
+	const numTries = 100
+	lck := NewInMemoryRepositoryLock()
+	assert.NoErr(t, lck.Lock(repo, 0*time.Second))
+	for i := 0; i < numTries; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			assert.True(t, lck.Lock(repo, 0*time.Second) != nil, "lock of already locked repo should return error")
+		}()
+	}
+	assert.NoErr(t, waitWithTimeout(&wg, 1*time.Second))
+	assert.NoErr(t, lck.Unlock(repo, 0*time.Second))
+	for i := 0; i < numTries; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			assert.True(t, lck.Unlock(repo, 0*time.Second) != nil, "unlock of already unlocked repo should return error")
+		}()
+	}
+	assert.NoErr(t, waitWithTimeout(&wg, 1*time.Second))
+}
+
 func TestSingleLock(t *testing.T) {
 	rl := NewInMemoryRepositoryLock()
 	key := "fakeid"