debug: add json and improve

Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>

hscontrol/state/debug_test.go

@@ -0,0 +1,78 @@
+package state
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNodeStoreDebugString(t *testing.T) {
+	tests := []struct {
+		name     string
+		setupFn  func() *NodeStore
+		contains []string
+	}{
+		{
+			name: "empty nodestore",
+			setupFn: func() *NodeStore {
+				return NewNodeStore(nil, allowAllPeersFunc)
+			},
+			contains: []string{
+				"=== NodeStore Debug Information ===",
+				"Total Nodes: 0",
+				"Users with Nodes: 0",
+				"NodeKey Index: 0 entries",
+			},
+		},
+		{
+			name: "nodestore with data",
+			setupFn: func() *NodeStore {
+				node1 := createTestNode(1, 1, "user1", "node1")
+				node2 := createTestNode(2, 2, "user2", "node2")
+
+				store := NewNodeStore(nil, allowAllPeersFunc)
+				store.Start()
+
+				store.PutNode(node1)
+				store.PutNode(node2)
+
+				return store
+			},
+			contains: []string{
+				"Total Nodes: 2",
+				"Users with Nodes: 2",
+				"Peer Relationships:",
+				"NodeKey Index: 2 entries",
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			store := tt.setupFn()
+			if store.writeQueue != nil {
+				defer store.Stop()
+			}
+
+			debugStr := store.DebugString()
+
+			for _, expected := range tt.contains {
+				assert.Contains(t, debugStr, expected,
+					"Debug string should contain: %s\nActual debug:\n%s", expected, debugStr)
+			}
+		})
+	}
+}
+
+func TestDebugRegistrationCache(t *testing.T) {
+	// Create a minimal NodeStore for testing debug methods
+	store := NewNodeStore(nil, allowAllPeersFunc)
+
+	debugStr := store.DebugString()
+
+	// Should contain basic debug information
+	assert.Contains(t, debugStr, "=== NodeStore Debug Information ===")
+	assert.Contains(t, debugStr, "Total Nodes: 0")
+	assert.Contains(t, debugStr, "Users with Nodes: 0")
+	assert.Contains(t, debugStr, "NodeKey Index: 0 entries")
+}