feat: 初始化小米 IoT (MIoT) 智能家居 Go 库

- 实现 MIoT 客户端核心功能（MQTT 连接、设备管理、属性读写）
- 支持云端 API 调用与局域网设备发现（mDNS）
- 集成国际化（i18n）多语言支持
- 添加 MIoT 设备规约解析器（spec_parser）
- 包含单元测试与使用示例

miot/miot_lan_test.go

@@ -0,0 +1,166 @@
+// Package miot provides white-box tests for miot_lan.go LAN device control.
+package miot
+
+import "testing"
+
+func TestLanDeviceState_String(t *testing.T) {
+	tests := []struct {
+		state LanDeviceState
+		want  string
+	}{
+		{LanDeviceFresh, "fresh"},
+		{LanDevicePing1, "ping1"},
+		{LanDevicePing2, "ping2"},
+		{LanDevicePing3, "ping3"},
+		{LanDeviceDead, "dead"},
+		{LanDeviceState(99), "unknown"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.want, func(t *testing.T) {
+			if got := tt.state.String(); got != tt.want {
+				t.Errorf("LanDeviceState(%d).String() = %q, want %q", tt.state, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestHexDecode_Valid(t *testing.T) {
+	data, err := hexDecode("abcdef0123456789abcdef0123456789abcdef0123456789abcdef0123456789")
+	if err != nil {
+		t.Fatalf("hexDecode failed: %v", err)
+	}
+	if len(data) != 32 {
+		t.Errorf("hexDecode len = %d, want 32", len(data))
+	}
+}
+
+func TestHexDecode_InvalidChar(t *testing.T) {
+	_, err := hexDecode("ghij")
+	if err == nil {
+		t.Error("hexDecode with invalid chars should error")
+	}
+}
+
+func TestHexDecode_Empty(t *testing.T) {
+	data, err := hexDecode("")
+	if err != nil {
+		t.Fatalf("hexDecode empty: %v", err)
+	}
+	if len(data) != 0 {
+		t.Errorf("len = %d, want 0", len(data))
+	}
+}
+
+func TestMd5Sum_KnownValue(t *testing.T) {
+	result := md5Sum([]byte("hello"))
+	if len(result) != 16 {
+		t.Errorf("md5Sum len = %d, want 16", len(result))
+	}
+	result2 := md5Sum([]byte("hello"))
+	if result != result2 {
+		t.Error("md5Sum should be deterministic")
+	}
+}
+
+func TestMd5Sum_DifferentInput(t *testing.T) {
+	r1 := md5Sum([]byte("hello"))
+	r2 := md5Sum([]byte("world"))
+	if r1 == r2 {
+		t.Error("different inputs should produce different hashes")
+	}
+}
+
+func TestMinFloat(t *testing.T) {
+	if minFloat(1.0, 2.0) != 1.0 {
+		t.Error("minFloat(1, 2) should be 1")
+	}
+	if minFloat(2.0, 1.0) != 1.0 {
+		t.Error("minFloat(2, 1) should be 1")
+	}
+	if minFloat(5.5, 5.5) != 5.5 {
+		t.Error("minFloat(5.5, 5.5) should be 5.5")
+	}
+}
+
+func TestToInt_Helper(t *testing.T) {
+	tests := []struct {
+		input   interface{}
+		wantVal int
+		wantOk  bool
+	}{
+		{float64(42), 42, true},
+		{int(100), 100, true},
+		{int64(200), 200, true},
+		{"not a number", 0, false},
+		{nil, 0, false},
+		{true, 0, false},
+	}
+	for _, tt := range tests {
+		got, ok := toInt(tt.input)
+		if got != tt.wantVal || ok != tt.wantOk {
+			t.Errorf("toInt(%v) = (%d, %v), want (%d, %v)", tt.input, got, ok, tt.wantVal, tt.wantOk)
+		}
+	}
+}
+
+func TestIsNumeric(t *testing.T) {
+	tests := []struct {
+		input string
+		want  bool
+	}{
+		{"12345", true}, {"0", true}, {"000", true},
+		{"123abc", false}, {"abc", false},
+		{"", false}, {"12.34", false},
+	}
+	for _, tt := range tests {
+		got := isNumeric(tt.input)
+		if got != tt.want {
+			t.Errorf("isNumeric(%q) = %v, want %v", tt.input, got, tt.want)
+		}
+	}
+}
+
+func TestTrimNull(t *testing.T) {
+	tests := []struct {
+		input, want []byte
+	}{
+		{[]byte("hello\x00"), []byte("hello")},
+		{[]byte("hello\x00\x00"), []byte("hello")},
+		{[]byte("hello"), []byte("hello")},
+		{[]byte{0, 0}, []byte{}},
+		{[]byte{}, []byte{}},
+	}
+	for _, tt := range tests {
+		got := trimNull(tt.input)
+		if string(got) != string(tt.want) {
+			t.Errorf("trimNull(%v) = %v, want %v", tt.input, got, tt.want)
+		}
+	}
+}
+
+func TestMustParseUint64(t *testing.T) {
+	if mustParseUint64("1234567890") != 1234567890 {
+		t.Error("mustParseUint64('1234567890') wrong")
+	}
+	if mustParseUint64("0") != 0 {
+		t.Error("mustParseUint64('0') should be 0")
+	}
+}
+
+func TestLanDeviceState_IotaValues(t *testing.T) {
+	if int(LanDeviceFresh) != 0 {
+		t.Errorf("LanDeviceFresh = %d, want 0", LanDeviceFresh)
+	}
+	if int(LanDeviceDead) != 4 {
+		t.Errorf("LanDeviceDead = %d, want 4", LanDeviceDead)
+	}
+}
+
+func TestLanProtocolConstants(t *testing.T) {
+	if otHeader != 0x2131 {
+		t.Errorf("otHeader = %#x, want 0x2131", otHeader)
+	}
+	if otPort != 54321 {
+		t.Errorf("otPort = %d, want 54321", otPort)
+	}
+}