Fix: a data race condition after a timeout on an assert.Eventually call.

.gitignore

@@ -23,6 +23,8 @@ _testmain.go
 
 .DS_Store
 
+.idea
+
 # Output of "go test -c"
 /assert/assert.test
 /require/require.test

assert/assertions.go

@@ -13,6 +13,7 @@ import (
 	"runtime"
 	"runtime/debug"
 	"strings"
+	"sync"
 	"time"
 	"unicode"
 	"unicode/utf8"
@@ -1989,9 +1990,9 @@ func Eventually(t TestingT, condition func() bool, waitFor time.Duration, tick t
 	if h, ok := t.(tHelper); ok {
 		h.Helper()
 	}
-
 	ch := make(chan bool, 1)
-	checkCond := func() { ch <- condition() }
+	wg := &sync.WaitGroup{}
+	checkCond := func() { defer wg.Done(); ch <- condition() }
 
 	timer := time.NewTimer(waitFor)
 	defer timer.Stop()
@@ -2002,14 +2003,17 @@ func Eventually(t TestingT, condition func() bool, waitFor time.Duration, tick t
 	var tickC <-chan time.Time
 
 	// Check the condition once first on the initial call.
+	wg.Add(1)
 	go checkCond()
 
 	for {
 		select {
 		case <-timer.C:
+			wg.Wait()
 			return Fail(t, "Condition never satisfied", msgAndArgs...)
 		case <-tickC:
 			tickC = nil
+			wg.Add(1)
 			go checkCond()
 		case v := <-ch:
 			if v {

require/requirements_test.go

@@ -788,3 +788,22 @@ func TestEventuallyWithTTrue(t *testing.T) {
 	False(t, mockT.Failed, "Check should pass")
 	Equal(t, 2, counter, "Condition is expected to be called 2 times")
 }
+
+func TestEventuallyTimeout(t *testing.T) {
+	t.Parallel()
+
+	mockT := new(MockT)
+
+	counter := 0
+	condition := func() bool {
+		counter += 1
+		// this is here to check for data race conditions.
+		time.Sleep(20 * time.Millisecond)
+		return false
+	}
+	//Done to check for data race
+	counter += 1
+	Eventually(mockT, condition, 100*time.Millisecond, 20*time.Millisecond)
+	True(t, mockT.Failed, "check should fail")
+	Greater(t, counter, 2, "we should have more than one iteration")
+}