first commit

httpdl/retry_test.go

@@ -0,0 +1,28 @@
+package httpdl
+
+import (
+	"errors"
+	"net"
+	"strings"
+	"testing"
+)
+
+// retriesExhausted must wrap (not discard) the underlying cause, so main's
+// exit-code mapping can still tell a DNS failure from a refused connection.
+func TestRetriesExhausted(t *testing.T) {
+	cause := &net.DNSError{Err: "no such host", Name: "x.invalid", IsNotFound: true}
+
+	err := retriesExhausted("http://x", 5, cause)
+	var de *net.DNSError
+	if !errors.As(err, &de) {
+		t.Fatalf("dropped the cause: %v", err)
+	}
+	if !strings.Contains(err.Error(), "after 5 tries") {
+		t.Errorf("missing try count: %v", err)
+	}
+
+	// A single attempt did not "retry", so it must not claim it did.
+	if one := retriesExhausted("segment 0", 1, cause); strings.Contains(one.Error(), "tries") {
+		t.Errorf("single attempt should not mention tries: %v", one)
+	}
+}