Make the tests pass on a busy host (closes #240)

Tests that waited a few seconds for something to happen now wait 15 seconds.
The wait ends as soon as the condition holds, so a passing run takes no longer.

TestStreamNotDroppedWhileLinesArrive, the reconnect tests, the tests whose
requests pass a 2- or 4-second limit in the server, and
TestStreamDurationsCountSeconds run on a fake clock, so a stall on the host
cannot change their result. The reconnect tests also use a fake transport, so
a stall cannot reorder their requests.

The checkpoint tests give the writing connection a 30-second busy timeout, so
their limit can be 15 seconds and a checkpoint that waits for a read still
fails them.

Model: opus-5-5

README.md

@@ -434,14 +434,6 @@ The lists:
 - `pia`: VPN servers run by Private Internet Access. From
   [Private Internet Access](https://serverlist.piaservers.net/vpninfo/servers/v6),
   downloaded once a day.
-- `protonvpn`: the /24 networks that hold ProtonVPN servers. The whole /24 is
-  listed because the ProtonVPN-IPs README says traffic leaves from unpublished
-  addresses in it. From the public
-  [ProtonVPN-IPs](https://github.com/tn3w/ProtonVPN-IPs) mirror of Proton's
-  server list, downloaded once a day.
-- `protonvpn_entry`: the IPv4 and IPv6 addresses of ProtonVPN servers. From the
-  same [ProtonVPN-IPs](https://github.com/tn3w/ProtonVPN-IPs) mirror, downloaded
-  once a day.
 - `spamhaus_drop` and `spamhaus_dropv6`: IPv4 and IPv6 networks hijacked or
   leased by spammers or cyber criminals, according to Spamhaus. From
   [Spamhaus DROP](https://www.spamhaus.org/blocklists/do-not-route-or-peer/),

TODO.md

@@ -53,9 +53,6 @@ problem the run finds.
 
 # Completed Steps
 
-- 2026-11-10: the IP lookup checks the `protonvpn` list of ProtonVPN's /24
-  networks, from a public mirror of Proton's server list (closes
-  https://git.eeqj.de/sneak/routewatch/issues/236).
 - 2026-11-10: the tests no longer fail when a busy host stalls for several
   seconds. Most such waits are now 15 seconds. The test of the stream's idle
   timeout runs on a fake clock (closes #240)

internal/iplist/iplist.go

@@ -51,11 +51,6 @@ const (
 	// FormatIVPNJSON is IVPN's JSON server list. The hosts of its wireguard
 	// and openvpn gateways have their addresses in host and v2ray.
 	FormatIVPNJSON
-
-	// FormatProtonVPN has one address or network per line, with comment lines
-	// that start with #. Unlike FormatLines, a file with no addresses or
-	// networks fails.
-	FormatProtonVPN
 )
 
 // List is one public IP list.

internal/iplist/iplist_internal_test.go

@@ -70,19 +70,6 @@ const (
 	"config":{"api":{"ips":["192.0.2.73"]}}}`
 )
 
-// protonVPNBody is a small file in the format of the ProtonVPN-IPs list.
-const protonVPNBody = "#\n# protonvpn_ip_ranges.txt\n" +
-	"# https://github.com/tn3w/ProtonVPN-IPs\n#\n" +
-	"# The /24 block of every advertised IPv4.\n#\n" +
-	"192.0.2.0/24\n198.51.100.0/24\n"
-
-// protonVPNEntryBody is a small file in the format of the ProtonVPN-IPs list
-// of server addresses.
-const protonVPNEntryBody = "#\n# protonvpn_entry_ips.txt\n" +
-	"# https://github.com/tn3w/ProtonVPN-IPs\n#\n" +
-	"# Entry IPs clients connect to, resolved from ProtonVPN hostnames.\n#\n" +
-	"192.0.2.80\n2001:db8::80\n"
-
 // errorPage is a file that is no list, as a publisher's error page is.
 const errorPage = "<!DOCTYPE html>\n<html></html>\n"
 
@@ -280,20 +267,6 @@ func TestLookupFindsVPNServers(t *testing.T) {
 			listed:   []string{"192.0.2.70", "192.0.2.71", "192.0.2.72"},
 			unlisted: []string{"192.0.2.73", "2001:db8::70"},
 		},
-		{
-			name:     "ProtonVPN networks",
-			format:   FormatProtonVPN,
-			body:     protonVPNBody,
-			listed:   []string{"192.0.2.0", "192.0.2.255", "198.51.100.7"},
-			unlisted: []string{"192.0.3.1", "2001:db8::90"},
-		},
-		{
-			name:     "ProtonVPN server addresses",
-			format:   FormatProtonVPN,
-			body:     protonVPNEntryBody,
-			listed:   []string{"192.0.2.80", "2001:db8::80"},
-			unlisted: []string{"192.0.2.81", "2001:db8::81"},
-		},
 	})
 }
 
@@ -506,31 +479,6 @@ func TestWrongVPNDocumentFailsToParse(t *testing.T) {
 	}
 }
 
-// TestWrongProtonVPNDocumentFailsToParse parses documents that are not a
-// ProtonVPN-IPs list. Each fails, so none can replace a good copy.
-func TestWrongProtonVPNDocumentFailsToParse(t *testing.T) {
-	t.Parallel()
-
-	bodies := map[string]string{
-		"error page":    errorPage,
-		"JSON":          `{"status":"ok"}`,
-		"comments only": "#\n# protonvpn_ip_ranges.txt\n#\n",
-		"bad network":   "192.0.2.0/24\nexample\n",
-		"an empty file": "",
-	}
-
-	for name, body := range bodies {
-		t.Run(name, func(t *testing.T) {
-			t.Parallel()
-
-			addresses, err := parse(strings.NewReader(body), FormatProtonVPN)
-			if err == nil {
-				t.Errorf("parse returned %v and no error", addresses.Ranges())
-			}
-		})
-	}
-}
-
 // TestLookupMarksVPNLists looks up an address on a VPN list and on another
 // list. Only the VPN list's listing says it is one.
 func TestLookupMarksVPNLists(t *testing.T) {
@@ -575,10 +523,7 @@ func TestPublicListsMarkTheVPNLists(t *testing.T) {
 		}
 	}
 
-	want := []string{
+	want := []string{"ivpn", "mullvad", "nordvpn", "pia", "x4bnet", "x4bnet_v6"}
-		"ivpn", "mullvad", "nordvpn", "pia", "protonvpn", "protonvpn_entry",
-		"x4bnet", "x4bnet_v6",
-	}
 	if !slices.Equal(got, want) {
 		t.Errorf("VPN lists %v, want %v", got, want)
 	}

internal/iplist/lists.go

@@ -146,30 +146,6 @@ func vpnLists() []List {
 			Format:      FormatPIAJSON,
 			VPN:         true,
 		},
-		{
-			// Proton's own server list needs a logged-in session, so this is
-			// the public ProtonVPN-IPs mirror of it. Proton publishes only
-			// the addresses clients connect to. The mirror's README says
-			// traffic leaves from others in the same /24, so this file of
-			// /24 networks is the one it says to use for detecting exits.
-			Name: "protonvpn",
-			Description: "In a /24 network that holds a server of the " +
-				"ProtonVPN service",
-			URL: "https://raw.githubusercontent.com/tn3w/ProtonVPN-IPs/master/" +
-				"protonvpn_ip_ranges.txt",
-			Interval: vpnListInterval,
-			Format:   FormatProtonVPN,
-			VPN:      true,
-		},
-		{
-			Name:        "protonvpn_entry",
-			Description: "A server of the ProtonVPN service",
-			URL: "https://raw.githubusercontent.com/tn3w/ProtonVPN-IPs/master/" +
-				"protonvpn_entry_ips.txt",
-			Interval: vpnListInterval,
-			Format:   FormatProtonVPN,
-			VPN:      true,
-		},
 		{
 			Name: "x4bnet",
 			Description: "In an IPv4 network of a VPN service, according to " +

internal/iplist/parse.go

@@ -58,8 +58,6 @@ func parse(r io.Reader, format Format) (*netipx.IPSet, error) {
 		return parsePIA(r)
 	case FormatIVPNJSON:
 		return parseIVPN(r)
-	case FormatProtonVPN:
-		return parseProtonVPN(r)
 	default:
 		return nil, errUnknownFormat
 	}
@@ -331,22 +329,6 @@ func parseIVPN(r io.Reader) (*netipx.IPSet, error) {
 	return addressSet(texts)
 }
 
-// parseProtonVPN returns the addresses or networks in a ProtonVPN-IPs list. A
-// file with no addresses or networks fails, because the service always has
-// servers.
-func parseProtonVPN(r io.Reader) (*netipx.IPSet, error) {
-	addresses, err := parseLines(r, addAddressOrNetwork)
-	if err != nil {
-		return nil, err
-	}
-
-	if len(addresses.Ranges()) == 0 {
-		return nil, errNoAddresses
-	}
-
-	return addresses, nil
-}
-
 // readJSON reads r to its end and decodes it, as one JSON document, into v.
 func readJSON(r io.Reader, v any) error {
 	data, err := io.ReadAll(r)