AUTH-5682 Org token flow in Access logins should pass CF_AppSession cookie

- Refactor HandleRedirects function and add unit tests
- Move signal test to its own file because of OS specific instructions

token/signal_test.go

@@ -0,0 +1,54 @@
+//go:build linux || darwin
+
+package token
+
+import (
+	"os"
+	"syscall"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestSignalHandler(t *testing.T) {
+	sigHandler := signalHandler{signals: []os.Signal{syscall.SIGUSR1}}
+	handlerRan := false
+	done := make(chan struct{})
+	timer := time.NewTimer(time.Second)
+	sigHandler.register(func() {
+		handlerRan = true
+		done <- struct{}{}
+	})
+
+	p, err := os.FindProcess(os.Getpid())
+	require.Nil(t, err)
+	p.Signal(syscall.SIGUSR1)
+
+	// Blocks for up to one second to make sure the handler callback runs before the assert.
+	select {
+	case <-done:
+		assert.True(t, handlerRan)
+	case <-timer.C:
+		t.Fail()
+	}
+	sigHandler.deregister()
+}
+
+func TestSignalHandlerClose(t *testing.T) {
+	sigHandler := signalHandler{signals: []os.Signal{syscall.SIGUSR1}}
+	done := make(chan struct{})
+	timer := time.NewTimer(time.Second)
+	sigHandler.register(func() { done <- struct{}{} })
+	sigHandler.deregister()
+
+	p, err := os.FindProcess(os.Getpid())
+	require.Nil(t, err)
+	p.Signal(syscall.SIGUSR1)
+	select {
+	case <-done:
+		t.Fail()
+	case <-timer.C:
+	}
+}