Manager: add 'canary' test to all timeout checker tests

The canary test asserts that certain constants still have the expected
value. Lowering those constants is good for testing the timeout stuff with
the actual Flamenco Manager + Worker (without having to wait 5 minutes for
it to kick in), but it's too easy to accidentally run the unit tests and
get cryptic errors about everything failing horribly and miserably when
you leave those constants low.

internal/manager/timeout_checker/tasks_test.go

@@ -19,6 +19,8 @@ import (
 const taskTimeout = 20 * time.Minute
 
 func TestTimeoutCheckerTiming(t *testing.T) {
+	canaryTest(t)
+
 	ttc, finish, mocks := timeoutCheckerTestFixtures(t)
 	defer finish()
 
@@ -81,12 +83,7 @@ func TestTimeoutCheckerTiming(t *testing.T) {
 }
 
 func TestTaskTimeout(t *testing.T) {
-	// Canary test: if these constants do not have the expected value, the test
-	// will fail rather cryptically.
-	if !assert.Equal(t, 5*time.Minute, timeoutInitialSleep, "timeoutInitialSleep does not have the expected value") ||
-		!assert.Equal(t, 1*time.Minute, timeoutCheckInterval, "timeoutCheckInterval does not have the expected value") {
-		t.FailNow()
-	}
+	canaryTest(t)
 
 	ttc, finish, mocks := timeoutCheckerTestFixtures(t)
 	defer finish()

internal/manager/timeout_checker/timeout_checker_test.go

@@ -6,9 +6,11 @@ import (
 	"context"
 	"sync"
 	"testing"
+	"time"
 
 	"github.com/benbjohnson/clock"
 	"github.com/golang/mock/gomock"
+	"github.com/stretchr/testify/assert"
 
 	"git.blender.org/flamenco/internal/manager/timeout_checker/mocks"
 )
@@ -72,3 +74,15 @@ func timeoutCheckerTestFixtures(t *testing.T) (*TimeoutChecker, func(), *Timeout
 	)
 	return sm, finish, mocks
 }
+
+// canaryTest will abort the current test if timing constants do not have the
+// expected value. Unit tests will fail rather cryptically by themselves if the
+// timing of the timeout checker is not what is expected.
+func canaryTest(t *testing.T) {
+	if assert.Equal(t, 5*time.Minute, timeoutInitialSleep, "timeoutInitialSleep does not have the expected value") &&
+		assert.Equal(t, 1*time.Minute, timeoutCheckInterval, "timeoutCheckInterval does not have the expected value") {
+		return
+	}
+	t.Fatal("timing-related constants are not as expected by the unit test, preemptively aborting.")
+	t.FailNow()
+}

internal/manager/timeout_checker/workers_test.go

@@ -15,6 +15,8 @@ import (
 const workerTimeout = 20 * time.Minute
 
 func TestWorkerTimeout(t *testing.T) {
+	canaryTest(t)
+
 	ttc, finish, mocks := timeoutCheckerTestFixtures(t)
 	defer finish()