Make browser sidecar on-demand (#44)

backend/internal/latest/browser_test.go

@@ -1,6 +1,10 @@
 package latest
 
-import "testing"
+import (
+	"context"
+	"errors"
+	"testing"
+)
 
 func TestKaganeAPIURL(t *testing.T) {
 	const uuid = "019f84bc-9ba0-7ed9-86f5-8b905ec7c28b"
@@ -57,3 +61,17 @@ func TestNovelfullSeriesURL(t *testing.T) {
 		})
 	}
 }
+func TestClassifyBrowserInterruption(t *testing.T) {
+	if err := classifyBrowserError(context.Background(), true, context.Canceled); !errors.Is(err, errBrowserInterrupted) {
+		t.Fatalf("classifyBrowserError(context.Canceled) = %v, want browser interruption", err)
+	}
+	if err := classifyBrowserError(context.Background(), false, context.Canceled); errors.Is(err, errBrowserInterrupted) {
+		t.Fatalf("ordinary cancellation misclassified as browser interruption: %v", err)
+	}
+
+	caller, cancel := context.WithCancel(context.Background())
+	cancel()
+	if err := classifyBrowserError(caller, true, context.Canceled); errors.Is(err, errBrowserInterrupted) {
+		t.Fatalf("caller cancellation misclassified as browser interruption: %v", err)
+	}
+}