chore: add example

Makefile

@@ -1,13 +1,14 @@
 .PHONY: all test-color lint try-4-real
 
-all: test-color lint try-4-real
+all: test-color lint
+	go mod tidy
 
 test-color:
 	go install github.com/haunt98/go-test-color@latest
-	go-test-color -race -failfast ./...
+	go-test-color -race -failfast .
 
 lint:
-	golangci-lint run ./...
+	golangci-lint run .
 
 try-4-real:
-	go run .
+	go run . -race ./example/...

example/example_test.go

@@ -0,0 +1,35 @@
+package example
+
+import (
+	"testing"
+	"time"
+)
+
+const longTime = time.Second * 2
+
+func TestPassShortTime(t *testing.T) {
+}
+
+func TestPassLongTime(t *testing.T) {
+	time.Sleep(longTime)
+}
+
+func TestFailShorTime(t *testing.T) {
+	t.Fail()
+}
+
+func TestFailLongTime(t *testing.T) {
+	time.Sleep(longTime)
+	t.Fail()
+}
+
+func TestFailShorTimeParallel(t *testing.T) {
+	t.Parallel()
+	t.Fail()
+}
+
+func TestFailLongTimeParallel(t *testing.T) {
+	t.Parallel()
+	time.Sleep(longTime)
+	t.Fail()
+}