add test for Eventual

Author: FGasper

internal/util/eventual_test.go

@@ -0,0 +1,37 @@
+package util
+
+import (
+	"time"
+
+	"github.com/10gen/migration-verifier/option"
+)
+
+func (s *UnitTestSuite) TestEventual() {
+	eventual := NewEventual[int]()
+
+	s.Assert().Equal(
+		option.None[int](),
+		eventual.Get(),
+		"Get() should return empty",
+	)
+
+	select {
+	case <-eventual.Ready():
+		s.Require().Fail("should not be ready")
+	case <-time.NewTimer(time.Second).C:
+	}
+
+	eventual.Set(123)
+
+	select {
+	case <-eventual.Ready():
+	case <-time.NewTimer(time.Second).C:
+		s.Require().Fail("should be ready")
+	}
+
+	s.Assert().Equal(
+		option.Some(123),
+		eventual.Get(),
+		"Get() should return the value",
+	)
+}