integration/tsic: drop unused watchIPN

ipn.Notify.NetMap is gone upstream; nothing called it.

integration/tsic/tsic.go

@@ -1134,101 +1134,6 @@ func (t *TailscaleInContainer) Netmap() (*netmap.NetworkMap, error) {
 	return nm, nil
 }
 
-// Netmap returns the current Netmap ([netmap.NetworkMap]) of the Tailscale instance.
-// This implementation is based on getting the netmap from `tailscale debug watch-ipn`
-// as there seem to be some weirdness omitting endpoint and DERP info if we use
-// Patch updates.
-// This implementation works on all supported versions.
-// func (t *TailscaleInContainer) Netmap() (*netmap.NetworkMap, error) {
-// 	// watch-ipn will only give an update if something is happening,
-// 	// since we send keep alives, the worst case for this should be
-// 	// 1 minute, but set a slightly more conservative time.
-// 	ctx, _ := context.WithTimeout(context.Background(), 3*time.Minute)
-
-// 	notify, err := t.watchIPN(ctx)
-// 	if err != nil {
-// 		return nil, err
-// 	}
-
-// 	if notify.NetMap == nil {
-// 		return nil, fmt.Errorf("no netmap present in ipn.Notify")
-// 	}
-
-// 	return notify.NetMap, nil
-// }
-
-// watchIPN watches `tailscale debug watch-ipn` for a [ipn.Notify] object until
-// it gets one that has a [netmap.NetworkMap].
-//
-//nolint:unused
-func (t *TailscaleInContainer) watchIPN(ctx context.Context) (*ipn.Notify, error) {
-	pr, pw := io.Pipe()
-
-	type result struct {
-		notify *ipn.Notify
-		err    error
-	}
-
-	resultChan := make(chan result, 1)
-
-	// There is no good way to kill the goroutine with watch-ipn,
-	// so make a nice func to send a kill command to issue when
-	// we are done.
-	killWatcher := func() {
-		stdout, stderr, err := t.Execute([]string{
-			"/bin/sh", "-c", `kill $(ps aux | grep "tailscale debug watch-ipn" | grep -v grep | awk '{print $1}') || true`,
-		})
-		if err != nil {
-			log.Printf("killing tailscale watcher, \nstdout: %s\nstderr: %s\nerr: %s", stdout, stderr, err)
-		}
-	}
-
-	go func() {
-		_, _ = t.container.Exec(
-			// Prior to 1.56, the initial "Connected." message was printed to stdout,
-			// filter out with grep.
-			[]string{"/bin/sh", "-c", `tailscale debug watch-ipn | grep -v "Connected."`},
-			dockertest.ExecOptions{
-				// The interesting output is sent to stdout, so ignore stderr.
-				StdOut: pw,
-				// StdErr: pw,
-			},
-		)
-	}()
-
-	go func() {
-		decoder := json.NewDecoder(pr)
-		for decoder.More() {
-			var notify ipn.Notify
-
-			err := decoder.Decode(&notify)
-			if err != nil {
-				resultChan <- result{nil, fmt.Errorf("parse notify: %w", err)}
-			}
-
-			if notify.NetMap != nil { //nolint:staticcheck // SA1019: NetMap is still populated on the platforms our integration containers run; migrating to InitialStatus/PeerChanges is a separate change
-				resultChan <- result{&notify, nil}
-			}
-		}
-	}()
-
-	select {
-	case <-ctx.Done():
-		killWatcher()
-
-		return nil, ctx.Err()
-
-	case result := <-resultChan:
-		killWatcher()
-
-		if result.err != nil {
-			return nil, result.err
-		}
-
-		return result.notify, nil
-	}
-}
-
 func (t *TailscaleInContainer) DebugDERPRegion(region string) (*ipnstate.DebugDERPRegionReport, error) {
 	if !util.TailscaleVersionNewerOrEqual("1.34", t.version) {
 		panic("tsic.DebugDERPRegion() called with unsupported version: " + t.version)